Title: History of the Harvard College Observatory During the Period 1840-1890
Author: Baker, Daniel W.
Language: English
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                                HISTORY
                                OF THE
                      HARVARD COLLEGE OBSERVATORY
                     DURING THE PERIOD 1840–1890.


                                  BY
                           DANIEL W. BAKER.

            _Reprinted from the Boston Evening Traveller._

                              CAMBRIDGE.
                                 1890.



                               PREFACE.


A careful study of the early history of the Harvard College Observatory
has been made by Mr. DANIEL W. BAKER. Many facts were thus
brought to light which had not appeared in print. A series of newspaper
articles was accordingly prepared, which were published in the Boston
“Evening Traveller” on six successive Saturdays, beginning August 2,
1890. Much of this material appearing to be of sufficient value for
preservation in a more permanent form, it has been reprinted in the
present pamphlet, with slight alterations, and with the addition of
the illustrations given on page 25. The parts numbered IV. and V.
originally appeared together as a single article. Reproductions have
been made of some of the illustrations. The articles were originally
addressed, not to professional astronomers, but to the general
public, and are to be regarded as a popular description of the work
accomplished at the Harvard College Observatory during the first fifty
years of its existence.

                                                 EDWARD C. PICKERING.

  HARVARD COLLEGE OBSERVATORY,
      _September 13, 1890_.



                                HISTORY
                                  OF
                   THE HARVARD COLLEGE OBSERVATORY.
                              1840–1890.


The present is the semi-centennial year of the Harvard College
Observatory. A precise date cannot be named for the beginning, but
in the early months of the year 1840 the institution was gradually
organized, and before midsummer became a tangible fact and a working
adjunct of the college.

While the first astronomical observation is of record Dec. 31, 1839,
it is well known that the observatory had not then an official staff,
the appointment of the first director being of date Feb. 12, 1840, and
the confirmation by the Board of Overseers somewhat later. Moreover,
this particular observation and others immediately following were made
in continuation of work begun elsewhere and not identified with the
college affairs.

The advance made in astronomical science during the 50 years past is
among the wonderful facts comprised in the record of the 19th century,
and it is true that since it became fairly organized and equipped,
Harvard College Observatory has been in the front rank in the march.
A review of this progress so far as pertaining to the institution at
Cambridge, is, therefore, timely. A history of 50 years, embodying so
many facts of the first importance and interest as does this, cannot,
even with the most resolute purpose as respects brevity, be disposed of
in a single chapter. This, accordingly, will be the first of a series.
The reader may be assured at the outset that the topics to be touched
upon are various and in themselves attractive, and that, so far as
possible, technicalities will be shunned.

Regarding the period of beginning just referred to as the blossoming,
whence has followed abundant fruitage, it may be remarked that a
long time passed between the budding and the blossoming, and that
indications of the flow of a vital current are recognizable at as
remote a date as 1761. In that year the sloop owned by the province
of Massachusetts was fitted out at public cost to convey Prof.
John Winthrop and others connected with the college, provided with
instruments belonging to the college, to Newfoundland, for observation
of a transit of Venus. In 1780, notwithstanding the financial straits
incident to the war, the commonwealth provided a small vessel of war,
called a “galley,” to take Prof. Samuel Williams, of the college,
and party to Penobscot to observe a total eclipse of the sun. The
first definite record pointing to a college observatory is of date
1805, when John Lowell, the uncle of that John Lowell who founded
the Lowell Institute, being in Paris, consulted with Delambre, an
astronomer of note, and procured from him written instructions as to
suitable buildings and instruments for an observatory. This document
was sent to the college authorities at Cambridge. No official action
followed. The next of record is that the college authorities in 1815
appointed a committee to consider and report upon an eligible plan
for an observatory. This is supposed to have been the first corporate
action taken in the United States, having such an object in view. The
doings of this committee are notable in two particulars, at least.
They brought into official relations with the college for the first
time, the man who was destined to be the builder and organizer of the
observatory, 25 years later, William Cranch Bond.

He was about to visit Europe and was appointed the agent of the college
to obtain information as to the construction and instrumental equipment
of the observatory at Greenwich, and to make such plans, drawings,
etc., as would enable him or another to construct an astronomical
observatory at Cambridge; also to ascertain from the makers the cost
of certain principal instruments like those at Greenwich. He performed
the service and reported in detail in the following year. That nothing
practical came of it for a quarter of a century was not owing to the
will, but comparatively speaking, to the poverty of the college.

This result followed, however,—and it may be reckoned the second
notable circumstance—that, upon his return, Mr. Bond constructed
the model of an astronomical dome, the operative plan of which was
the same as that of the great dome, built in 1844, and which has
been in satisfactory use at Cambridge to the present time. The chief
peculiarity of its mechanism is in the method of rotation by means
of smoothly-turned spheres of iron. The dome rests on these at
equi-distant points, and, being set in motion by suitable gearing, the
iron balls sustaining its weight roll along a level circular track of
iron, the circumference of which is equal to that of the dome. The
method was unlike that previously in use. It appears to have been
original with Mr. Bond, as is perhaps evinced by a remark in his
report for 1848 referring to the matter: “If carefully examined, it
will be found that this arrangement is as perfect in theory as it is
appropriate and convenient in practice.” Experience has shown that
spheres of hard bronze are more serviceable than those of iron, and
bronze is now used.

[Illustration: THE DANA HOUSE.]

The record indicates that an observatory did not cease to be a coveted
object at any time during the 25 years prior to 1840. Two antecedent
events, in themselves of importance, combined to bring the long
cherished project to a happy issue,—the accession of Josiah Quincy to
the presidency of the college and the action of Congress in authorizing
what came to be popularly known as the “Wilkes Exploring Expedition.”
The purpose of the expedition in part was to establish the latitudes
and longitudes of uncharted places in distant parts of the world where
American commerce was extending, and in part to investigate natural
phenomena, including the facts of terrestrial magnetism. Having,
after much delay, got an adequate appropriation, the naval department
employed the best available talent of the country for the conduct of
the enterprise.

Mr. Bond was engaged to make at his private observatory in Dorchester,
Mass., investigations to fix a zero of longitude, whence final
reference to Greenwich might be had, and to make a continuous record of
magnetic observations at Dorchester for comparison with like records
obtained at distant points by the expedition itself. As preliminary
to the latter work, Mr. Bond tested in an isolated observatory in
Dorchester the magnetic instruments with which the expedition was to be
equipped.

Mr. Bond’s talents were as well known at Cambridge as at Washington.
What Mr. Quincy did in the premises can best be stated in his own
words: “Early in the year 1839, the exploring expedition then being in
the Southern ocean, it occurred to the president of the university that
if Mr. Bond could be induced to transfer his residence and apparatus
to Cambridge and pursue his observations there, under the auspices of
the university, it would have an important influence in clearing the
way for an establishment of an efficient observatory in connection with
that seminary, by the increase of the apparatus at its command, by the
interest which the observations making by Mr. Bond were calculated to
excite, and, by drawing the attention of the citizens of Boston and
its vicinity to the great inadequacy of the means possessed by the
university for efficient astronomical observations, create a desire and
a disposition to supply them.”

This proposition, Mr. Quincy says in another connection, he made
without having consulted with the corporation. That body sanctioned
his action by making a formal contract with Mr. Bond, of date Nov. 30,
1839, the agreement on Mr. Bond’s part being to make the transfer as
proposed. Steps were at once taken by the college authorities to secure
a subscription of $100 each from 30 different gentlemen, which sum was
applied, under Mr. Bond’s direction, in alterations and additions to
a dwelling house owned by the college and known as the “Dana house.”
It still stands upon its original site at the junction of Quincy
and Harvard streets, the lot being the southeast corner of what are
distinctively called “the college grounds.”

The cupola which crowns the roof is a reminder and proof of a part
of these alterations: for within it was set up one of the telescopes
of the first college observatory, the cupola when constructed being
suitably domed for the purpose. Something practical in astronomy had
always been taught in the college course. In this way, or possibly
by Mr. Bond himself, the position of Harvard Hall on the college
grounds had been determined. Thus, in a paper published by him in
1833 in the Memoirs of the American Academy, he gives the position of
his observatory in Dorchester as “0°-3′-15″ east of Harvard Hall in
Cambridge.”

That the astronomical equipment possessed by the college before Mr.
Bond’s coming did not amount to the beginning of a proper observatory,
sufficiently appears by a contemporary letter of Prof. Joseph Lovering,
written in response to an official inquiry. He says that the college
had at the time “no instrument of much value for determining either
time or position, and no place more convenient for using instruments
than an open field, or a window which might accidentally open in the
right direction.” He gives the inventory, comprising an astronomical
clock, which, he says, cannot be relied on for accurate time; a small
transit instrument, which at one time was loaned to Dr. Bowditch, but
returned, he having found it of little value; two reflecting telescopes
of three feet and two feet focal length; and a refractor of three
feet focal, which three, he says, “answered decently well for showing
the moon, Jupiter’s satellites, Saturn’s ring, etc., to the students,
but were very imperfect for any nice observation.” These, with an
astronomical quadrant and a common quadrant, complete the list. The
list of instruments brought by Mr. Bond does not appear in the printed
records, but in the paper above referred to he names his instruments
used at Dorchester as a Gregorian reflector of 30 inches focus,
equatorially mounted, an achromatic telescope of 40 inches focus, a
Borda’s circle, a Ramsden’s sextant, and two transit clocks. The clocks
he describes as “excellent,” and says that they had mercurial pendulums.

In the early observations of Mr. Bond at Cambridge, priority was
given to the work begun at Dorchester for the naval department. In
the college record a considerable part of the routine is classed as
meteorology, with reference, chiefly, to the earth’s magnetism. The
scheme of observation in this department was, however, much broadened,
and in this the observatory appears to have performed its first
notable service to pure science and to have assumed a place that gave
it international recognition. For these observations the best known
apparatus was procured and put into service in a building on the
college grounds set at a distance from the Dana house, but connected
therewith by a covered way. It was known as the “Lloyd apparatus.”
It consisted chiefly of three magnetometers, one for indicating
declination, one for horizontal force and the third for vertical force.

It was the product of the same firm in England which had made like
instruments for the British government for use at meteorological
stations at Greenwich, Eng., Toronto, Can., St. Helena, Cape of Good
Hope, Bombay, Madras, Singapore and Van Diemen’s Land. The magnetic
observations at Cambridge were conducted according to the same
formula as that in use at these British stations, with a purpose of
co-operation. In this cosmical investigation the German Meteorological
Association, having many observatories under its direction, and
the Russian government, having magnetic stations at various points
between the borders of China and the Arctic Circle, joined. This Lloyd
apparatus was the gift of the American Academy of Arts and Sciences, by
vote of April 22, 1840, and was of the value of $1000.

[Illustration: MAIN OBSERVATORY BUILDING, SHOWING THE DIRECTOR’S
RESIDENCE AND THE GREAT DOME.]

Many interesting particulars of the early days of Harvard College
observatory are given in the first volume of printed annals of the
institution. In the reading an essential fact is to be kept in mind,
the difference of the pecuniary standards of that and the present
time. The writer of an official document of 1843, was, in view of
that difference, neither inexact nor ironical when he characterized a
conditional offer of $5000 for the observatory, made that year by Hon.
David Sears, as “a munificent proposal.” It was soon found that the
Dana house site would serve only temporarily, and on Sept. 4, 1841,
action was taken for the building of a permanent observatory. Soon
afterwards the present observatory grounds, then known as “Summer House
hill,” were bought.

Up to this time astronomical work had been carried on at the Dana
house to the extent possible with the few instruments of precision at
command, much of it by Mr. W. C. Bond, Jr., whose decease, in 1842,
was regarded a loss to science. The contract of the senior Mr. Bond
with the United States government ended in 1842, and in July of that
year a movement was made having in view the purchase of a first-class
telescope, but it was a matter of inquiry as to cost, etc., only. Under
ordinary circumstances what was thus sought for, a proper observatory
building and a telescope equal to the more difficult problems of
astronomy, would have been slowly arrived at.

But early in March, 1843, the great comet of that year suddenly
appeared in the evening sky, near to the sun. It was an astonishing
phenomenon, and wrought the popular as well as the scientific mind into
a state of excitement.

The comet had passed perihelion on Feb. 27, and was seen at one place
in New England on the 28th, close to the sun. During its brightest
period it was visible in the daytime at one place in this section of
the country from 7.30 A.M. to 3 P.M., when clouds intervened; and in
Mexico from 9 A.M. till sunset. It passed but about 90,000 miles from
the sun’s surface and through more than 300,000 miles of the sun’s
corona, its velocity then being 350 miles per second. Its head was
small, but its tail large and brilliant. The total light emitted by the
meteor is stated by Prof. Loomis to have been equal to that of the moon
at midnight in a clear sky. By the telescope its tail could be traced
over a computed distance of 108,000,000 miles, so that had it been
pointed towards the earth it would have passed through the planet’s
atmosphere and 15,000,000 miles beyond.

The professor names as its notable characteristics “its small
perihelion distance, nearly as small as is physically possible, and its
prodigious length of tail.” It continued visible into the following
month. It is known in the books as “the great comet of 1843,” but for
reasons which will appear, it might well be called “the Harvard comet.”
The friends of the young institution at Cambridge perceived that the
moment was opportune for an appeal to the moneyed public. The prevalent
curiosity as to the visitor could not be gratified by the observers at
the Dana house.

They had no instruments fit for the occasion. An altitude-and-azimuth
instrument, which had been used in the state survey of 1831, was
borrowed and mounted in the cupola, and thus, on March 9, an
observation was first made; but nothing came of the endeavor, it
being found impossible to secure permanent adjustments. The next
thing done was to call a meeting of citizens in Boston. The chairman
was Hon. Abbot Lawrence. Addresses were made by Hon. John Pickering,
Prof. Benjamin Peirce, Hon. William Appleton and Hon. S. A. Eliot. A
financial committee was appointed, and subscriptions to the amount of
$25,000 were obtained in Boston, Salem, New Bedford and Nantucket.

Thus encouraged, the official board of the college negotiated for
the purchase of the best telescope that could be produced in Europe,
a refractor of 15 inches aperture, equatorially mounted, the makers
being Merz & Mahler of Munich. The spot for building a massive stone
supporting pier on Summer House hill was fixed Aug. 12, 1843, and
ground was broken for the work on Aug. 15.

These were the experiences which Prof. Benjamin Peirce had in mind when
in later years he spoke in eulogy of Prof. Bond, then deceased, in
phrase which is both of historical and biographical interest. Having
mentioned some of the early difficulties, he said: “When, in 1839, Mr.
Bond was drawn to Cambridge by the strong hand of President Quincy,
when the cause of the observatory was undertaken by the unflinching
and irresistible vigor of our friend J. Ingersoll Bowditch, when
even the heavens came to our assistance, and that wonderful comet
of 1843 excited most opportunely a universal interest in celestial
phenomena,—it was then apparent that the affection for Mr. Bond was the
chief strength of the occasion, and to that we were mainly indebted for
the successful attempt to obtain the unrivalled equatorial and to lay
the foundations of the observatory.” No proper biography of Mr. Bond,
whose career was an honor to his country, has ever been published. A
sketch, the facts for which have largely been derived from original
sources, may fittingly be given as the next number in this series.



                                  II.


A casual glance at the circumstances of the beginning of the famous
observatory in the neighboring city of Cambridge will show that a most
important contribution to the success of that enterprise was made by
the first director of the observatory, Prof. W. C. Bond. The more
diligently those circumstances are studied, the stronger will be the
conviction that his work, while it was that of designer and organizer,
was also somewhat better in the sense of being more rare in quality;
that his presence and enthusiasm gave the institution vitality. The
record of his life gives him title to rank among eminent Americans.

William Cranch Bond was born in Portland, Me., Sept. 9, 1789. He was
the youngest son of William and Hannah (Cranch) Bond, who were natives
of England. The family was of distinction there, and is genealogically
traceable to the time of William the Conqueror, or earlier. The
Brandon manor is said to have been granted by that monarch to the
ancestor of this line, and to have been held by the family through many
generations. William Bond was born In Plymouth, Eng. Richard Cranch,
an uncle of Hannah, settled in Braintree, Mass, in 1751. The name, in
himself and his descendants, became distinguished in the annals of the
province and commonwealth. From him William Bond received information
which induced him to emigrate to this country. He located for business
purposes at Portland, then Falmouth, and engaged in cutting ship-timber
at Frenchman’s bay, sending the commodity to England. He made a voyage
thence to England, returning with his wife and elder children. The
timber business proved in the end unprofitable and he removed to Boston
in 1793, where he established himself in his vocation of clockmaker and
silversmith, his stand being at the corner of Milk and Marlboro, now
Washington street. The youth of William C. Bond was, accordingly, spent
in Boston, where he had such education as the common schools afforded.
Indeed, that he did not have fully that privilege, may be inferred
from his remark quoted by Josiah Quincy, that pecuniary restrictions
“obliged me to become an apprentice to my father before I had learned
the multiplication table.” Mainly he was self-taught, though doubtless
he derived instruction from his father, who was a well-informed man,
and from some of the Cranch relatives, who were of good education. The
traditions of the family and the facts of his career, indicate his
mental quality to have been that of genius, one trait of which is that
it absorbs congenial knowledge from unpromising materials and amidst
adverse conditions.

[Illustration: PROF. W. C. BOND.]

His eldest sister wrote of him as having been, at the age of 14,
“a slender boy with soft gray eyes and silky, brown hair, quick to
observe, yet shrinking from notice, and sensitive to excess.” She adds,
in reference to his early-developed tastes: “The first that I remember,
was his intense anxiety about the expected total eclipse of the sun of
June 16, 1806. He had then no instrument of his own, but watched the
event from a house-top on Summer street through a telescope belonging
to Mr. Francis Gray, to which, somehow, he got access. In so doing he
injured his eyes and for a long time was troubled in his vision.” An
elder brother writes Of him at this early period: “He was the mildest
and best-tempered boy I ever knew, and his remarkable mechanical genius
showed itself very early.” He adds that in devising and making bits
of apparatus that boys use in their sports, William was chief among
his comrades. His early apprenticeship in the clockmaking business
undoubtedly gave a fortunate discipline to this natural ingenuity,
by confining his experiments pretty closely to the facilities of his
father’s workshop as to tools and materials.

He found or made “idle time” enough before he was 15 years old to
construct a reliable shop chronometer. It had to be a fixture, for
lacking a suitable spring he contrived to run it by weights.

When he was about 16 years of age he made a good working quadrant out
of ebony and boxwood, the only materials he had. His son, G. P. Bond,
wrote of this instrument, years afterwards: “It is no rude affair, but
every part, especially the graduation, the most difficult of all, shows
the neatness, patience, and accuracy of a practised artist. A better
witness to the progress he had already made in astronomy could not be
desired. It is all that the materials would admit of, and proves that
he must have been, even then, irrevocably devoted to astronomy.”

How these “eccentricities of genius” were looked upon by the senior Mr.
Bond does not appear, but, at any rate, William was made a member of
the firm about the date of his majority, and forthwith the clockmaking
business was expanded to include the rating, repairing and making of
chronometers. Astronomy could now go hand in hand with “business.” He
must have had the means of ascertaining the true local time before he
was himself owner of an instrument suited to that purpose. He made
his first seagoing chronometer in 1812, and it was the first made in
America. Its engraved trade mark was “Wm. C. Bond, 1812.” It at once
went into service, and satisfactorily stood the test of a voyage to
and from the East Indies. For making this he had a working model;
the stationary or shop chronometer of 1804 was made according to a
description he found in an old French book of a chronometer used by
La Perouse, the navigator. In 1810 the business of the Bonds was
removed to Congress street. About the same time the family removed
to Dorchester where for a while they occupied, as tenants, different
houses.

Mr. Bond himself said in his later years that what first gave him a
determination for astronomy was his experience of the total eclipse
of 1806. Once aroused, the feeling never ceased to have sway, and it
modified all his business ambitions as a chronometer maker. But as
such an artisan he had excuse in the eyes of the practical minded for
his loved explorations into the starry depths. In the lack of proper
instruments his earliest observations were made by crude methods,
which yet gave proof of his originality and of the fascination which
the study had for him. It was soon after 1811 that he first gained
recognition from any one competent to pass judgment upon his essential
mental qualities. On Sept. 4, 1811, Prof. John Farrar of Harvard
College first caught sight of a comet in the western sky. He appears
to have at once notified Dr. Nathaniel Bowditch of Salem, and they
two, and a few others in New England who had telescopes, traced its
subsequent progress. Each of the two published an account of his
observations in the Memoirs of the American Academy. Prof. Farrar
having given in his introductory paragraph the date of his first
observation, adds that the comet had been seen earlier by Mr. Bond of
Dorchester, whom he calls “William Bond, Jr.,” and says that Mr. Bond
had “obligingly favored” him with the following notices:

I remarked on the 21st of April a faint, whitish light near the
constellation Canis Major, projecting a tail about one degree in
length, and set down its place as follows: Right ascension, 106°;
declination, 9° S. April 24, right ascension, 108°; declination, 7° or
8° S. Its motion and the situation of its tail convinced me that it
was a comet. I noticed it several times in May, and supposed that its
motion was toward the western part of the constellation Leo.

By messages coming in sailing ships it was learned subsequently to
September that the comet had been seen in Europe on March 25. Its
perihelion passage was September 12, 1811.

The elder brother already quoted says of these early days: “I suppose
it would cause the astronomer royal to laugh could he see the first
transit instrument used by us at Dorchester, a strip of brass nailed to
the east end of the house, with a hole in it to see a fixed star and
note its transit; this in 1813. When we moved into the Hawes house, he
procured a good granite block; we dug a deep hole and placed it at the
west end of the house and got Mr. Alger to cast a stand for the transit
instrument, a small one, which I think belonged to Harvard College.
From this time he began to live among the stars.”

The facts thus recorded of the beginning of Mr. Bond’s career show
his zeal and watchfulness as an amateur in astronomy, and that up to
the date of the comet’s appearance, and later, he had no personal
acquaintance with men of science in the vicinity, since he informed
none of them of what he had seen. When, months afterwards, Prof. Farrar
inquired about it, the young discoverer was able to report from his
memoranda no more than the degrees of position, without the minutes and
seconds, and to say that he “supposed” the comet to be moving towards
the constellation Leo, circumstances indicating that a strip of brass
with a hole in it and a home-made boxwood quadrant were all that was
astronomically in use at Dorchester as late as 1811.

That this experience with the comet was a fortunate turning point in
Mr. Bond’s career is evinced by Prof. Farrar’s genial recognition in
the paper published in the organ of American Science, where he might
excusably have ignored so crude a record as that which was the best
Mr. Bond could supply, and by the appearance not long afterwards, at
the west end of the Hawes house in Dorchester, of a loaned telescope
belonging to Harvard College.

There is no doubt that whatever previously had been lacking of
opportunity to gain knowledge of the technics of astronomical science
was now fully within his reach and that henceforth he had the best
possible of instructors and counsellors so far as he had occasion
for any. Mr. George P. Bond writes of his father: “He has mentioned
the names of Dr. Nathaniel Bowditch, Prof. Farrar and Tutor Clapp
as those from whom he received most encouragement to continue the
cultivation of astronomy. Upon his friendly intercourse with the
eminent mathematician and astronomer first named he often dwelt with
peculiar pleasure and warmth of feeling.” The name of one other of the
godfathers of the young scientist is entitled to be mentioned, that of
Josiah Quincy. The lady above quoted gives an account of the setting
up of the first telescope at Dorchester by her brother, and says that
through it could be seen the satellites of Jupiter and the rings of
Saturn. She adds that in the pursuit of astronomy up to this period
“he had had no assistance whatever except from the genial kindness of
Hon. Josiah Quincy, who had early recognized the future astronomer in
the unpretending boy in the watchmaker’s shop on Congress street, and
whose kindness and encouragement never failed throughout the subsequent
years.”

That these men found their patronage to have been well bestowed is
manifest from the action taken four years after the date of the comet
by the college in making Mr. Bond its delegate and agent. The board
of that year consisted of President Kirkland, John Lathrop, D.D.,
Christopher Gore, LL.D., John Davis, LL.D., John Lowell, LL.D., and
John Phillips. It is of record that the moving spirits in the matter
were Prof. Farrar and Dr. Bowditch, and they were appointed a committee
to prepare technical written instructions to the agent as to the
general scope of his inquiry.

During his visit abroad, Mr. Bond married his cousin, Selina Cranch, of
Kingsbridge, in Devonshire, the date being July 18, 1819. Soon after
his return he purchased a house near to his father’s residence in
Dorchester, and erected on the premises a small wooden building, which
he carefully equipped as an astronomical observatory. Its position is
that meant in the official references to the observatory at Dorchester,
and is about 45 feet southerly of the present south line of Cottage
street, and 360 feet southeasterly of the centre of the New York &
New England railroad bridge, over that street. Here, as one of his
brief biographers remarks, “no eclipse or occultation escaped him,
though occupied in business during the day in Boston,” and here Mr.
Quincy found him in 1839, busy in his work for the Navy Department. The
period which had elapsed since the setting of the granite block and the
poising upon it of the borrowed telescope had been for Mr. Bond one of
constant and rapid advance in the astronomer’s art. The Cottage street
observatory was built about the year 1823.

Referring to the period between 1823, or a little earlier, and 1839,
Mr. G. P. Bond writes of his father: “As soon as his circumstances
permitted, he imported more perfect apparatus from Europe and continued
to add to his collection until it was the best in the country.” And
he adds this statement, which is highly suggestive as respects the
enthusiasm with which the accomplished and successful chronometer maker
entered upon the broader and loftier mission which destiny had in
reserve for him: “When appointed by the Navy Department to the charge
of astronomical and other observations, he forthwith laid out a sum of
money on instruments and buildings more than ten times greater than
the annual salary (to continue but four years), which he had himself
proposed as an adequate compensation for all necessary expenses, and
his own time, besides.”

During a few years prior to 1830, he gathered materials for
investigating the comparative rates of chronometers at sea and on
shore. Subsequently he communicated to the American Academy the results
reached, and in this paper effectually disposed of the scientific
question involved, so far as it related to the interests of navigation.
The authority for this statement is Mr. G. P. Bond, who also says that
about the same time his father conducted a series of experiments to
ascertain the influence of changes of temperature in the presence of
large surfaces of iron upon the performance of chronometers; and adds
that “although the conclusions arrived at were at variance with the
opinions of men high in authority in such matters, they are now known
to be correct.”

President Quincy, in making his overture, was dealing with no novice,
and, certainly, no stranger. Some intimation of what Mr. Bond had
attained to is contained in the remarks of Prof. Benjamin Peirce
spoken in the obituary proceedings of the American Academy in 1859,
consequent upon Mr. Bond’s decease, though the reference is to a longer
period. The instrument alluded to is the great equatorial at Cambridge.
Prof. Peirce said: “In his original investigations he naturally
restrained himself to those forms of observation which were fully
within the reach of his own resources. He did not, therefore, seek
those inquiries which could only be accomplished by long, intricate,
and profound mathematical computations, but preferred those which
were purely dependent upon the thorough discipline of the senses. He
consequently availed himself less of the remarkable capacity of his
instrument for delicate and refined measurements than of its exquisite
optical qualities. But when observations were required which must be
passed over to the computer, his skill was not wanting to the occasion.
Thus, in conjunction with Major Graham, he made that choice series of
observations from which the latitude of the observatory was determined.”

[Illustration: THE BOND HOUSE, DORCHESTER. View looking to the
southwest. The Observatory stood contiguous to the west end.]

To this testimony as to Prof. Bond’s skill as an observer maybe
added that of Mr. G. P. Bond as to his diligence and zeal: “There is
something to my mind appalling in the contemplation of my father’s
labors, from the time when he was first enabled to indulge freely his
passion for observation. The accumulated volumes filled with manuscript
records give me a shudder at the thought of the weary frame and
straining eye, the exposure, and the long, sleepless nights that they
suggest.”

Ex-President Quincy, upon the obituary occasion referred to, made
this interesting statement as to the initiation of his project for
Mr. Bond’s removal to Cambridge: “This proposal, so in unison with
his pursuits and talents, I expected would be received with pleasure.
But it was far otherwise. In the spirit of that innate modesty which
predominated in his character, and apparently cast a shadow over
all his excellent qualities and attainments, Mr. Bond hesitated,
doubted his qualifications for the position. He said his habits were
not adapted to public station; that our combined apparatus would be
small, and that something great might be expected; that he preferred
independence in obscurity to responsibility in an elevated position. He
raised many other objections, which need not here be repeated, as they
were overcome.”

At the date of this interview the president found Mr. Bond well
established in a profitable manufacturing business, happily situated
in his domestic and neighborhood surroundings, with an avocation
fascinating enough to occupy all his leisure and a fame extensive
enough to satisfy his own modest estimate of his abilities. There was
no pecuniary betterment for Mr. Bond in the suggested change. Mr.
Quincy could only offer him what he had already, a family domicile; so
that the proposal might warrant an adaptation of Sidney Smith’s famous
phrase and be described as an invitation to come to Cambridge and
“cultivate astronomy upon a little oatmeal.” In so phrasing it there
is no disparagement of the college; it was the day of small things, of
pennies, not dollars, in the college treasury. But the event speaks the
praises of Mr. Quincy, whose sagacity was unfailing and before whose
persuasiveness and energy difficulties in administration were wont to
give way, and of Mr. Bond, whose unselfishness and loyalty to science
were proof against pecuniary considerations. In mental traits each was
in many respects the complement of the other, and it is not too much to
say that these two were pre-eminently the founders and builders of the
observatory.

The official report for 1846 states that up to that time the labors of
Mr. Bond had been “entirely unrequited, except by the gratification of
his love of science and of home,” and suggests that this devotion to
the institution at Cambridge was the more marked in that during the
preceding spring he had declined “the almost unlimited offers made to
him by the administration at Washington to induce him to take charge of
the observatory there.” It is known, also, that frequent expenditures
of his own money were made during this period for current expenses
and for things convenient in conducting the observatory, sums small
severally, no doubt, but considerable in the total. In 1846 a sum equal
to the proposed salaries for the next two years was subscribed by
citizens of Boston, and in 1849 the official board was able to report
that “through a bequest of $100,000 made by Edward Bromfield Phillips
they should thereafter be relieved from anxiety as to the payment of
salaries and current expenses.” Various official documents evince that
during the first eight years Mr. Bond is to be regarded not in the
character of an employee, but a benefactor of the college; that his
labors were deemed by those most familiar with them to be indispensable
and invaluable, and that his friendship for the college, manifested
in all ways, and especially in his declination of the liberal offers
coming from Washington, was appreciated and honored. The date of Mr.
Bond’s appointment as director of the observatory was Feb. 12, 1840,
though the confirmation by the corporation was later. He was given the
honorary degree of A.M., by Harvard in 1842.



                                 III.


In resuming consecutively the story of the half-century’s progress of
Harvard College Observatory, which was interrupted in the preceding
number to give place to a biographical notice of Prof. W. C. Bond, it
may be remarked that the period of his official term, which covered 19
years, was fruitful in great discoveries and events in the astronomical
department of science. Harvard Observatory contributed its full share,
though the greatest of all was that which gave fame to Le Verrier, the
French astronomer, the discovery of the planet Neptune. In September,
1844, the observatory building on Summer House hill had been completed
to the extent proposed at that time, and the instruments were
transferred from the Dana house.

A new transit instrument, imported by the United States government
for the use of the Northeastern Boundary Commission, was set up in
December, and used during the winter in observations for ascertaining
the latitude, as previously described in the quotation from Prof.
Peirce. The results were collated and discussed by Prof. Peirce in
the memoirs of the American Academy. These were the first notable
observations of precision at the new observatory. The longitude was
also determined by the most accurate method then known, observation of
occultations and moon culminations and comparison of a considerable
number of chronometers transported to and from Greenwich by ocean
steamers. In the ultimate determination the record made by several
hundred chronometers thus sent to and fro, and observations of
occultations, etc., in Dorchester, Cambridge, Brooklyn, Philadelphia
and Washington, ranging through many years, were brought into the
account. The earliest were observations made in Philadelphia in 1769.
After the laying of the Atlantic cable still closer comparisons with
the zero of Greenwich were possible. The position of the observatory as
finally determined and now officially of record is: Longitude, 71° 7′
44.85″, west; latitude, 42° 22′ 47.6″, north. As showing the error of
the best attainable results by use of chronometers it may be remarked
that by that method the central tower of the observatory was located at
a point on the lawn half way between the front door of the director’s
dwelling house and Garden street. The discrepancy is about 320 feet.

About the time of the first determination Commodore Owen of the British
Navy was making an official survey of the coast of New Brunswick and
Nova Scotia. Having confidence in what had been done at Cambridge
he took that station for his zero in preparing his official report,
ultimate reference being made to Greenwich. The first importation
of chronometers appears to have been made jointly by Prof. Bond and
Commodore Owen. When the report was submitted it was challenged by some
of the British Board of Admiralty, who believed that the longitude of
Halifax was better known. In due course Prof. Bond was inquired of, and
his letter addressed to the board of admiralty, in explanation of the
technicalities, proved convincing and its conclusions were cordially
accepted, with thanks by Admiral Beaufort on behalf of the board.
The officers-in-chief of the United States Coast Survey, and of the
exploring expedition severally adopted the Cambridge meridian as the
zero in preparing their official reports.

A new instrument purchased by the observatory, a 2¾-inch equatorial,
permitted accurate observations to be made of the solar eclipses of
1845 and 1846, the comets of the same years, the transit of Mercury in
1845 and of the newly discovered planet Neptune.

The 15-inch equatorial was set up on June 23 and 24, 1847. Certain
nebulæ and the planet Saturn were the first subjects of study.
Discoveries of importance were made in each field of investigation. The
report of the visiting committee for 1848 notes the discovery by Prof.
Bond on Sept. 19 of that year of the eighth satellite of Saturn, and
speaks of it as “the only addition to the solar system ever made on the
continent of America.”

The few years immediately following the date of the great telescope may
be called the romantic period in the history of the observatory. There
was no instrument on this continent to be compared to it, and it had
but one equal in Europe.

While the director of the observatory kept cool enough to utilize it to
the utmost, he manifestly shared in the enthusiasm. One of the earliest
to inquire what could be seen by it was Edward Everett, president of
the college from 1846. Prof. Bond responded by letter on July 26,
1847, named several matters and ended by saying: “But I must recollect
that you require of me only a brief account of our telescope. The
objects revealed to us by this excellent instrument are so numerous
and interesting that it is difficult to know where to stop.” On Sept.
22 following Prof. Bond wrote to the president: “You will rejoice with
me that the great nebula in Orion has yielded to the powers of our
incomparable telescope.”

He explains the reason for his rejoicing by saying that this nebula and
that of Andromeda had hitherto been the strongholds of the “nebular
theory,” or the theory that the nebulæ are masses of matter in process
of condensation into systems.

Now, the mass in Orion which, he said, had defied the telescopes
of both the Herschels, and, at first, that of Lord Rosse, had been
resolved into innumerable distinct points of light, or separate stars,
by the Cambridge refractor, whose only competitor in the search was
Lord Rosse’s instrument, “the largest reflector in the world.”

The phrase “incomparable telescope” was warranted. Nor does the
didactic suggestion of the proverb about the new broom apply; for
more than 30 years afterwards the present director of the observatory
had occasion to say: “In 1877 besides the photometric measures of the
satellites of Mars, a series of measures for their positions was also
made. The number of these observations was second only to that obtained
with the great telescope at Washington.” Of the work done two years
later, he says: “Of the satellites of Mars 1348 measurements were made,
Deimos being last seen at this observatory as it gradually receded
from the earth. This is remarkable, as our telescope has entered into
competition with the largest telescopes of the world, some of which
admitted two or three times as much light.”

On Nov. 7, 1848, a transit circle was set up and it completed the set
of new instruments at first proposed for the observatory. Previous
to this date two new “comet seekers” had been received, the gifts
respectively of President Quincy and Mr. J. I. Bowditch. With these
in the six years beginning with 1845 the original discovery of ten
comets was made by Mr. G. P. Bond. In his report for 1846 Prof. Bond
says that during that year stellar and lunar observations had been made
in co-operation with like work done by observers of the United States
Coast Survey at West Point, Philadelphia and Nantucket, to determine
longitudes for the purposes of the coast survey.

[Illustration: W. C. BOND’S OBSERVATORY CHAIR.]

But visions of the sky were not the only matters of interest at the
observatory in this early period. The great telescope was poised
at a height of 13 feet from the floor of the dome, and its sweep was
from three degrees beyond the zenith to as many below the horizon.
The visual end of the instrument therefore might need to be set at
any point along an arc of 90 degrees, and an observer would have to
be something of an acrobat in successfully using it unless a suitable
chair could be obtained. There was none in the world that filled all
the requirements, and Prof. Bond invented and made one. It is in use,
unchanged, to this day, and by means of its ingeniously combined
wheels, cogs and pulleys the observer can quickly and easily place
himself anywhere along the vertical quarter circle and horizontal full
circle traversed by the eye-piece of the telescope.

Prior to 1845 a transfer of 12 chronometers to and from Greenwich,
Eng., had been made by Prof. Bond and Commodore Owen, for the
determination of the longitude of the observatory. Other chronometer
expeditions were conducted subsequently in co-operation with the United
States Coast Survey, the final one being in 1855. In the summing up of
results, 723 independent chronometer records were used. The magnitude
of this undertaking, as a whole, surpassed anything ever attempted in
any other country.

In his report, reviewing the year 1848, the director says; “Some
experiments made with the daguerreotype and talbotype processes for
obtaining impressions of the sun’s image formed by the telescope have
not been attended with complete success; however, we do not despair of
ultimate success.”

In the report for 1850 he is able to say: “With the assistance of Mr.
J. A. Whipple, daguerreotypist, we have obtained several impressions
of the star Vega. We have reason to believe this to be the first
successful experiment ever made either in this country or abroad. From
the facility with which these were executed with the aid of the great
equatorial, we were encouraged to hope for further progress.” In the
report of the following year he speaks of pictures of the moon and
stars obtained by this process, and adds with reference to his son’s
official visit to Europe that year: “Some of these daguerreotypes taken
by the aid of our great object glass excited the admiration of eminent
men in Europe, to whom Mr. G. P. Bond gave specimens.” In an official
letter he says of his son’s visit to Paris: “He attended in May a
meeting of the French Academy, and there presented a daguerreotype of
the moon taken with our large telescope.” Other specimens were placed
in the great exhibition of London, or World’s fair, of that year, and a
council medal was awarded for them.

This tour in Europe by the younger Mr. Bond makes an interesting
episode in the general record. He was everywhere cordially received
by men of science, a fact attributable in part, no doubt, to his own
reputation, but more especially to his being the representative of the
new observatory, already of fame, established in the distant West.

On arriving at Cronstadt he was surprised at meeting an officer of
the Russian government who had instructions to conduct him to the
imperial observatory at Pulkova, where, during his stay in Russia, he
was made the guest of the director of the observatory and given all
possible attentions and facilities, including the “great privilege” of
practically manipulating the instruments. Among these was the great
telescope, the rival of the Harvard equatorial. During the tour he
visited Sweden and saw a total eclipse of the sun. Among those from
whom he had friendly receptions were Baron Humboldt, Sir John Herschel,
Sir David Brewster, Sir G. B. Airy, Le Verrier, Biot Argelander, Gauss
and Hansen; also Lord Rosse, whose great telescope he had opportunity
to use.

In July, 1848, the wires of the magnetic telegraph were connected with
the observatory at the expense of the coast survey, for determining by
instant communication the longitude of certain principal cities in the
United States. There are suggestions of both the modern and the antique
world in the statement that in this first experience the electrical
apparatus of a department of the institution founded by John Harvard,
was connected with like apparatus in an observatory in the garden of
Peter Stuyvesant in New York city. These electrical experiments of
the coast survey were begun as early as 1844, between Washington and
Baltimore.

Various improvements of method had been made, and that most approved
was followed on this first occasion at Cambridge. The coast survey
officer in charge had for his assistants Prof. Bond at Cambridge and
Prof. Loomis in New York. An official letter of the electrician of the
Coast Survey Department says: “During these experiments Prof. Bond
conceived the idea of using an automatic circuit interrupter.”

Some question of priority as to this suggestion arose in later years.
It was doubtless a spontaneous and original thought with Prof. Bond,
though the suggestion appears to have been made earlier elsewhere,
but it had not been acted upon “from apprehension of injury to the
performance of an astronomical clock which must be used for the
purpose.” Experience proved eventually the apprehension to have been
groundless; but Prof. Bond’s suggestion avoided any liability of the
kind by proposing that an astronomical clock be made for the purpose.

In August, 1848, he received authority to have such a clock made at the
expense of the coast survey. Reverting to the matter in a subsequent
annual report, Prof. Bond says: “I caused such a clock to be made,
and it is found to answer perfectly the intended purpose. But another
and far more serious difficulty presented itself in the accurate
registry of the beats of the clock after being transmitted by the
galvanic circuit; and it was at this point that further progress in the
application of this method to astronomical observing was arrested.”

[Illustration: DAVID SEARS. The First Donor to the Observatory.]

Experimenters were busy at Philadelphia, Cincinnati, and elsewhere,
during the two years’ interval in attempts to solve this concomitant
problem, and with very considerable success. That none of these devices
quite filled the requirements is manifest by the fact that they did
not go into general use. But the perfected apparatus submitted to the
officer of the coast survey by Prof. Bond, April 12, 1850, did go into
such use. This instrument Prof. Bond stated to be the joint invention
of himself and his two sons, George P. and Richard F. Bond. It was
named at first from one of its peculiar parts, the “spring-governor,”
but the more comprehensive title of “chronograph” was later applied to
it.

While as a piece of mechanism, it was distinct from the “circuit
interrupter,” the two were used conjointly, and thus acting in
combination their operation in recording became known soon afterwards
in England as “the American method.” By this method the errors
suggested by the term “personal equation” are greatly diminished, and a
definiteness of record is attained, which permits the recording sheet
to be read by the eye to tenths and by scale and lens to hundredths of
a second. The successive sheets are the primary official record, and
being bound into volumes, become a part of the permanent archives.

The apparatus was at once put to use in the several telegraphic
stations of the coast survey; and one of the circumstances which made
Mr. G. P. Bond’s tour in Europe a notable one was its exhibition for
the first time there. It was shown in operation and explained in a
lecture by him before the Royal Astronomical Society, and also at
the annual meeting of the British Association for the Advancement of
Science. Through the urgency of Sir David Brewster and others it was
set up in the great exhibition at London in 1851, where a medal was
awarded for it. It had the highest award of the Massachusetts Mechanic
Association, a gold medal. It was adopted at the Greenwich observatory
soon after Mr. Bond’s exhibition of his model, and speedily throughout
Europe.

Soon after the electrical experiments of 1848 at the observatory the
wire was put into use to transmit to Boston and different railway
points, signals giving the true local time, these signals being
electrically responsive to the movement of an astronomical clock in
the observatory, the method of transmission being that of the “circuit
interrupter.” This system was at once adopted in England, wire
connections being made with a clock in Greenwich Observatory. This
time service of the Harvard Observatory, though continued during the
intermediate period, was not organized as at present until 1872.

In 1852 the officers of Harvard Observatory co-operated with Captain
Charles Wilkes in experiments for ascertaining the velocity of sound
under different atmospheric conditions. In these tests cannon were
fired near the observatory, at the arsenal in Watertown, at the
navy yard in Charlestown and at Fort Independence in the harbor,
the central observing point being the cupola of the State House in
Boston, where Captain Wilkes took his station. These experiments had
immediate reference to a reduction into proper form of data obtained
by the exploring expedition, wherein Captain Wilkes had caused surveys
of islands and groups in remote seas to be made by sound. In these
surveys, distances between points whence angles were projected were
determined by the firing of cannon at those points.

In 1855 an endowment of $10,000 was made by ex-President Quincy as a
memorial of his father, Josiah Quincy, a patriot of the revolution.
This fund was specifically applied to the publication of annals of the
observatory. The first volume was issued in 1856 and comprised a review
of the work of the preceding years, so that the series of which it is
the initial number makes a continuous record from the beginning. The
series now numbers nearly 25 volumes. The decease of Prof. W. C. Bond
occurred Jan. 29, 1859.



                                  IV.


George Phillips Bond was the second director of Harvard College
observatory, being the successor of his father, Prof. W. C. Bond.
The date of his appointment was 1859. He was born in Dorchester,
Mass., May 20, 1825, and graduated at Harvard in 1845. Thenceforth
until his decease Feb. 17, 1865, he was in the constant service of
the observatory. Prior to his taking the chief office his labors as
assistant had gained for him a professional reputation; he had shared
with his father the heavy task of organizing the observatory and
carrying it on with slender means; he was familiar with its routine,
and both by academical and practical training was peculiarly qualified
for the position.

His professional record therefore is not to be limited to his own
term as director. The computations required in the preparation of the
three early volumes of the annals were to a great extent his work,
and those pertaining to the chronometric expeditions between Boston
and Liverpool, were wholly by him. He was the discoverer of the dark
interior ring of Saturn, one of the first revelations of the great
telescope, and discoverer also, as already stated, of ten comets within
a brief period of years. In this cometary work it was his practice to
sweep the whole visible heavens once every month.

His observations of Saturn led to the adoption of a new theory as to
the constitution of the rings. During his term systematic observations
were made of certain nebulæ, particularly that in Orion. He conducted a
series of zone observations of faint stars near the equator, prepared a
plan of observation and reduction, and with his own hand graduated the
mica scales used in the work.

In 1860 he made an investigation of the brightness of certain celestial
objects, including the moon and the planets, the results of which have
a special value but are not identified with the Harvard photometrical
series of later years, which relates to fixed stars only. During his
term the formation of a star catalogue was begun, the observations
being made with the meridian circle and in right ascension only, and
much progress was made in picturing celestial objects by the camera,
the process having, with the disuse of Daguerre’s particular method,
gained the generic name of photography.

The prestige of the beginning and early successes of astronomical
photography attaches to the administration of the senior Bond; but
his son shared fully in the labors of thought, contrivance and
manipulation by which the original experiments were conducted, and in
appreciation of the future possibilities to science in this new method
of observation.

One evidence of this appears in a paper read by the younger Mr. Bond
before the American Academy on May 12, 1857, the immediate occasion
for its presentation being a most significant discovery made at the
observatory a few days earlier.

The paper says: “Daguerreotype images of the star Vega were obtained at
the observatory of Harvard College on July 17, 1850, and subsequently
impressions were taken from the double star Castor, exhibiting an
elongated disc, but no separation of its two components.

“These were the first, and until very recently, the only known
instances of the application of photography to the delineation of fixed
stars. A serious difficulty was interposed to further progress by the
want of suitable apparatus for communicating uniform sidereal motion
to the telescope.

“This has been supplied by replacing the original clock of the
great equatorial of the observatory by a new one, operating on the
principle of the spring-governor. Immediately upon its completion, a
new series of experiments was commenced. These have been successful
in transferring to the plate by the collodian process, images of
fixed stars to the fifth magnitude, inclusive, with singular and
unexpected precision. The most remarkable instances of success are the
simultaneous impressions of the group of stars composed of Mizar of the
second magnitude, its companion of the fourth and Alcor of the fifth
magnitude. The following measurements of the angular distance of the
companion from Mizar were taken from the plates.”

[Illustration: THE GOLD MEDAL; REVERSE SHOWING SIR WILLIAM HERSCHEL’S
40-FOOT TELESCOPE.]

A tabulated statement follows in the paper, giving dates from April 27
to May 8, with measurements from 13 photographic negatives produced on
the respective dates. The mean for distance is 14.49 seconds, and for
angle of position, 147°.80. For the same stars observed in the usual
way, Struve’s mean of six observations is, for distance, 14.40 seconds;
for positions, 147°.40.

Mr. Bond’s comments are: “The photographic method has thus in its first
efforts attained the limit of accuracy, beyond which it is not expected
the other can ever be sensibly advanced.

“Should photographic impressions be obtained from stars between the
sixth and eleventh magnitudes as has already been done for those
between the first and fifth, the extension given to our present means
of observation would be an advance in the science of stellar astronomy
of which it would scarcely be possible to exaggerate the importance.”

Mr. Bond made important contributions to the literature of the science
both in its mathematical and practical departments. Among the more
notable of the former was a paper on cometary calculations and the
method of mechanical quadratures, valuable in various respects, and
notable in having anticipated an important improvement afterward
given independently by Encke; also a paper on the use of equivalent
factors in the method of least squares. He wrote a monograph covering
observations of Donati’s comet of 1858, for which he was awarded the
gold medal of the Royal Astronomical Society and was the first of
his countrymen to obtain that distinction. He began a paper on the
nebula in Orion, which he did not live to complete, though during his
prolonged last illness he continued his labors upon it, and dictated to
an amanuensis long after strength to write had gone from him.

This paper was afterwards finished by Prof. T. H. Safford, then of
Harvard, now of Williams College observatory. A biographer says of Mr.
Bond: “Science to him was not a pastime but a serious calling, to be
pursued with the utmost conscientiousness and singleness of purpose.
That he did so much and did it so well, during the few years allotted
to him, must have been partly owing to an extreme reluctance to
dissipate his powers by beginning new works while the old were still
unfinished.” He received the honorary degree of A.M. from Harvard in
1853.

[Illustration: PRESIDENT JOSIAH QUINCY.]



                                  V.


Joseph Winlock was the third director of Harvard College observatory,
being appointed in 1866. He was born in Shelby county, Ky., Feb.
6, 1826; he graduated at Shelby College in 1845, and was professor
of mathematics and astronomy there until 1852. He was subsequently
in the service of the Naval Observatory at Washington, and, still
later, instructor in mathematics at the Naval Academy at Annapolis.
At different dates, he was superintendent of the work of preparation
of the Nautical Almanac. He continued in office as director of the
observatory until his decease, June 11, 1875.

His administration appears by the record to have been one of various
activity. A large amount of improved apparatus was added to the
resources of the observatory, partly by purchase and partly by
invention and making on the spot. He kept up the reputation of the
observatory, which has never failed from the start, for originality
and ingenuity in mechanical devices. It was during his term that the
transmission by electricity of the true solar time to railroad centres
and business points in all parts of New England became a regular
part of the observatory work, and, by the system which he organized,
compensation was made by corporations and individuals whose clocks were
put into electrical connection with that at the observatory.

A considerable revenue has thus annually been derived. Other
electrical apparatus of the observatory was modified and improved. A
“switch-board,” the device of his predecessor was much elaborated in
its mechanism, whereby the electrical current was made more available
and all the principal instruments were connected at will with the
chronographs.

In 1868 when he visited Europe he procured the apparatus of a meridian
circle of the latest device, the lenses being made in Cambridge. In
setting up the instrument he saw opportunity to introduce various
improvements in mechanism.

These were approved by experience and went into general use elsewhere.
Another of his devices was “for the determination of absolute
personal equation by mechanical means.” Other contrivances, either
wholly original or ingenious modifications of known apparatus, were
an attachment to the spectroscope for automatic recording, being a
modification of the chronograph: a combination of a stationary plane
mirror with a fixed lens of great focal length—from 30 to 40 feet—for
photographing the sun; a later improvement of this, by which the
telescope was reduced to a single fixed lens of long focus and small
aperture, chromatic aberration was avoided and the image on the plate
could be made as large as was convenient for measuring; and a change of
method by which the sun’s image could be taken at the principal focus
of the object glass and not beyond an eye-piece used to enlarge the
image.

In February, 1866, when he took charge of the observatory, the great
equatorial was applied to a series of observations of double, and
especially binary stars. This investigation was continued as steadily
as circumstances would permit till 1872, and the results appear in the
annals. In 1867 the first spectroscope owned by the observatory was
imported, and in 1869 another. Two small direct vision spectroscopes
were also procured during Prof. Winlock’s term.

In 1870 the new meridian circle, a superior instrument, was set up,
and on Nov. 10 of that year was begun the series of observations for
position of stars in the “Cambridge zone,” so called, or that between
50° north and 55° north and overlapping 10′ upon each contiguous zone.
This survey was a joint enterprise conducted by certain of the great
observatories of the world, that of Harvard being one of the two in
this country having a share in the work. On July 4, 1870, was begun a
series of photographs of the sun, and the work was continued nearly
or quite to the end of Prof. Winlock’s term, many hundred photographs
being comprised in the list.

[Illustration: HARVARD OBSERVATORY STATION IN SPAIN.]

In September, 1871, was begun an elaborate investigation of lunar
phenomena, which continued a year. In 1871 an arrangement was made with
the coast survey by which a series of photometric observations was
carried through, and for this a Zöllner astro-photometer was imported.
The work was continued three years, though not all of it at Cambridge.
The results are in the annals in 1878. The standard in using this
instrument was an artificial star produced by lamplight.

During this term two expeditions were made with apparatus for observing
total eclipses of the sun, and in both satisfactory results were
obtained. On the first occasion, of date Aug. 7, 1869, the station was
at Shelbyville, Ky., and on the second, of date Dec. 22, 1870, at Jerez
de la Frontera, in Spain. In 1867 daily observations in terrestrial
magnetism were made at the observatory for the purposes of the coast
survey. In March, 1869, experiments for determination of longitudes
were conducted on a continental scale, wire connection by relays being
made with San Francisco. In these experiments apparatus which had
been modified by Prof. Winlock was used and by this method, and also
by another which was applied, it proved that the time of passage of a
signal from Cambridge to San Francisco through the wire and six relays
was very nearly three-quarters of a second. Between Dec. 13, 1869, and
the summer of 1872, electric signals were sent by the Atlantic cable to
and from Brest in France, via Duxbury, Mass.

The purpose of these tests was to establish with precision the
difference of longitude between America and Europe. Prof. Winlock
supervised the work of preparing and engraving a series of plates
illustrating remarkable celestial objects. These gave special value to
the volume of annals in which they appeared, causing an unprecedented
demand for copies, so that it is now a rare book. His publications were
not numerous, but there is no doubt that his scholarship, versatility
and wide experience would have yielded valuable additions to the
literature of science had his life been prolonged.

The means at command during his term did not warrant the publication of
many volumes of annals. Though for nearly 10 years in office he did not
live to see any of his own observations published or even to complete
the work of his predecessors.

[Illustration: PROF. JOSEPH WINLOCK.]

During the term the permanent funds of the observatory were increased
by the bequest of James Hayward $20,000, and that of James Savage
$20,000. In 1870 a subscription of $12,450 was completed for purchase
of a new meridian circle. In the preceding term a gift of $10,000 was
made by William Sturgis for the publication fund. Prof. Winlock had the
honorary degree of A.M. from Harvard in 1868.



                                  VI.


Edward Charles Pickering, the present director of the observatory, was
appointed in 1876. He was born in Boston and is of the Essex family
of the name, Colonel Timothy Pickering being his great-grandfather.
He is a graduate of the Lawrence Scientific School of the class of
1865. During the next two years he was a teacher of mathematics in
that department of Harvard University. Later and up to the time of
his appointment as director, he was professor of physics at the
Massachusetts Institute of Technology.

A system of teaching physics called the “laboratory method” was
introduced by him there, and his text book illustrative of the method
has to a great extent been adopted by like institutes. Astronomy, as a
department of physics, came into the general course, and the attention
necessarily given, for the purposes of instruction in the institute,
to the technics of that subject, and to demonstration, served as
preparation and discipline for the official responsibilities which he
afterwards assumed.

He was a member of the Nautical Almanac party for observing in Iowa the
total solar eclipse of 1869, and was in like service in the following
year as a member of the United States Coast Survey party which observed
in Spain a recurrence of that event.

When he came to the directorship he found the observatory to be well
equipped as to instruments and its small working force efficiently
employed. Their number was but five or six, which was all the means of
the institution permitted of.

Like pecuniary restrictions continued until 1879, when a subscription
was completed providing for the institution, $5000 annually for
five years. Since then much larger gifts have been bestowed and
the instrumental equipment, in recent years especially, has been
whatever the latest demands or suggestions of science called for;
the observatory staff has been augmented from time to time, till it
now numbers about 40 persons, and the field of observation has been
extended to include the southern hemisphere of stars.

Upon the premises at Cambridge where in 1876 stood only the main
observatory and a lesser adjunct structure are now eight or ten others,
a cluster of small wooden buildings, domed or otherwise adapted
for astronomical uses, each containing a costly instrument of the
most approved device; and besides these a dwelling house has been
transformed into a hall, or rather a workshop of photography, and makes
the northernmost structure of the little city of science which has
been set upon Summer House hill.

Upon Mt. Wilson, in California, in north latitude, and Mt. Harvard,
in Peru, in south latitude, stand other unpretentious buildings, from
within which observers of the Harvard corps nightly search through the
translucent upper atmosphere of those regions to the respective poles.
This aggregation of means has yielded ample returns; to say which is to
signify that during the period under consideration the institution has
made a noteworthy record, and that its affairs have been guided with
befitting skill and judgment.

The total permanent funds at the beginning of the present term amounted
to about $170,000. The subscription for five years was intended for
immediate expenditure. At the end of that period a permanent fund
of $50,000 was obtained in like manner. In 1885 was added to the
permanent funds the bequest of Robert Treat Paine of his whole estate,
of which $164,198 became at once available. In 1886 was made the first
of a series of annual gifts of large sums of money by Mrs. Anna P.
Draper of New York as a memorial of her husband, the late Prof. Henry
Draper. These gifts have constantly been applied in furtherance of
photographical observation, especially in that line of investigation
which Dr. Draper himself began in his lifetime. In 1887 the bequest
of Uriah A. Boyden, amounting to $238,000, became available. This
bequest has conditions providing for astronomical work at considerable
elevations as free as possible from disturbing or obstructing
conditions of atmosphere. The income of the Paine fund may be applied
generally.

In pursuing the inquiries thus suggested, and others, the observatory
has adhered to its traditions, wherein original investigation has
been directed to the physical rather than the mathematical side of
astronomical science.

In his first annual report the present director outlined the immediate
policy, in the then restricted state of the finances, to be to keep
employed chiefly the two most costly and effective instruments, the
great equatorial and the meridian circle. The latter was already in
constant use in the work of the Cambridge zone.

With reference to the former, the report having named the several
specialties which the great observatories of this country had taken,
each to itself, said: “Photometry offers a field almost wholly
unexplored with large telescopes either in this country or abroad. It
has therefore been selected as that to which the greater portion of the
time of our telescope will be devoted.”

The investigation thus entered upon, together with the zone
observations just mentioned, and the continuation by ampler and in
some particulars radically different methods of investigations in
spectroscopy and photography, have given the institution a wide renown.
But hardly less conspicuous are certain other achievements in the long
list which makes the complete record. Without attempting to give any of
these rank, still less to repeat the list, a few may here be mentioned
upon the ground of their presumed popular interest.

In 1878 the utility of the time signal service was increased by causing
a time ball to be dropped every day at exact noon from a conspicuous
point in Boston within view of the shipping of the harbor. The time was
that of the meridian of the State House in Boston. When the standard
or 75th meridian time went into general use the practice was conformed
thereto. Indeed, the terms of the proposition might be reversed so as
to indicate that, in the final determination, the responsibility was
put upon the observatory to lead off in the matter.

There had been some discussion in the public prints and elsewhere of
the advisability of adopting a common meridian time for large areas.
In the report of the observatory for 1878 the theoretical presentation
of the case which had been made by those advocating the change was
sanctioned, and the new time was recommended as sure to be of public
convenience if generally accepted. General consent was somewhat
slow in its manifestation, but eventually the managers of all the
principal railroads of New England agreed to adopt the plan if the
time-signalling system of the observatory should be made to correspond
in respect to clock connections, time ball, etc.

This was instantly agreed to, and with due prior public notice the
new time went into use Nov. 18, 1883, and the Boston noon ball was
first dropped on that day at exactly five hours later than the noon of
Greenwich.

[Illustration: HARVARD COLLEGE OBSERVATORY.]

[Illustration: HARVARD STATION IN CALIFORNIA.]

In 1880 the full routine of meteorological observation was abandoned,
as several institutions were doing like work. The record of the
observatory in meteorology, which had continuously been kept up for 40
years, was reduced to proper form for printing, and was published in
1889. Certain observations of this kind have, however, been continued
in the record to the present date.

In 1888 a plan of co-operation was agreed upon with the N. E.
Meteorological Society and Mr. A. L. Rotch of the Blue Hill, Mass.,
Observatory, by which their results, which are of a comprehensive
character, have since been published in the annals of the Harvard
Observatory.

In 1877, in co-operation with Miss Mitchell of Vassar College
Observatory and her assistants, observations were made at Cambridge
for determining the longitude of the Vassar Observatory. Between
Feb. 15, 1879, and Jan. 3, 1880, like observations were made in
co-operation with officers of the Winchester Observatory of Yale
College to ascertain the longitude of that institution. Between June 2
and June 23, 1883, similar work was done to fix the longitude of McGill
Observatory in Montreal.

In the summer of 1888 ten evenings were given for observations for the
longitude of Smith College in Northampton. The observers were Miss
Byrd, teacher of astronomy at that college, and Miss Whitney, professor
of astronomy at Vassar College. Harvard’s contribution in the affair
consisted in providing facilities on the spot, including the use of a
transit instrument. These are instances, which among others go to show
that because of infinite painstaking at Harvard in the earlier years
it has become the Mecca to which all on this continent who wish to
be perfectly assured in the matter of longitude may prudently make a
pilgrimage.

In 1881 an arrangement was entered into for prompt communication as to
unusual celestial phenomena, discoveries, etc., among astronomers in
this country and in Europe. A cipher code, the invention of Messrs.
S. C. Chandler and John Ritchie, Jr., of the observatory staff, was
put into use. It is known as the “Science Observer Code,” and as it is
superior in accuracy to former codes has been widely recognized. In
1883 Harvard observatory was made the official distributing centre for
this class of news, by consent of the Smithsonian Institute, which had
previously performed the service.

Upon the occasion of the transit of Mercury across the sun’s disk in
May, 1878, all the available telescopes of the observatory were put to
use. The results, which included many photographs, were satisfactory,
considering the unfavorable weather. During the like transit of Venus,
on Dec. 6, 1882, six telescopes being in use, large additions were made
to the important data which planetary events of this kind may supply.

In August, 1886, a small party provided with instruments belonging
to the observatory made an expedition to Grenada, near the northern
coast of South America, for observation of the total solar eclipse of
that year. The expedition was in charge of Mr. W. H. Pickering, who
afterwards became a member of the observatory corps.

On Jan. 1, 1889, a large party, under the same direction, observed a
recurrence of the event in California. The observations were mainly
photographical. Excellent results were obtained in both cases, though
less in amount in the former, because of unfavorable weather.

Much has been done during the term in cometary investigation, but
latterly comets have been observed, as a rule, only immediately upon
discovery and towards the end of their visible period, or after they
had got beyond the reach of any but the most powerful telescopes.

In the summer of 1883 the director journeyed in Europe and visited
the principal observatories there. In the following annual report he
names as an important result of his journey the obtaining of copies of
unpublished manuscripts of Argelander and Sir William Herschel. The
former are memoranda of observations of variable stars and the latter
of observations made more than 100 years ago of the light of all stars
of Flamsteed’s catalogue.

The work on the Cambridge zone of stars was completed, as respects the
primary plan of observation, on Jan. 26, 1879, and at that stage was
regarded as one of the largest astronomical undertakings ever carried
through in this country.

The reduction of the data was accomplished in 1883, but as was
expected, a necessity for reobservation appeared in certain cases.
This work was done between Oct. 9, 1883 and Aug. 9, 1884. The observer
from the beginning had been Prof. William A. Rogers. He resigned
his position as assistant professor in the observatory in 1886, but
continued to serve as editor of the published results. The whole
series makes half a dozen or more volumes of the annals. The European
supervisors of the general undertaking, well pleased, apparently, with
the early instalments of manuscript returns, assigned to Harvard the
work of reobservation of another zone, that between 9° 50′ south and
14° 10′ south. This work is still in progress. Each zone comprises
about 8000 stars or nearly 17,000 in all.

The publications of the observatory during the present term in the form
of annals, and as contributions by members of the corps to various
journals of science, have been numerous and extensive. At the beginning
of the term but four volumes of annals had been issued, though about
an equal number were in some stage of progress in the printers’ hands,
publication having gone on slowly from lack of means. At the present
time the continuous series of 22 volumes has been issued, excepting
the second or supplementary parts in two or three instances. These
parts are nearly ready, and the manuscript for about half a dozen more
volumes in regular succession has, in part or whole, been given to the
printer.

A review of what has been done during the present term in the
departments of photometry, spectroscopy and photography will be
comprised in the next and closing number of this series.



                                 VII.


Agreeably to the announcement of the annual report of Harvard
College Observatory for 1877, as to photometry, a beginning was made
by constructing a photometer suitable to be attached to the great
telescope. Other photometers have been devised at different times for
use independently. One of the earliest was applied during the year
beginning Oct. 12, 1877, in measuring the light of all known satellites
excepting the two inner ones of Uranus, which are too faint to be
discerned, even by the great telescope. The first prolonged observation
entered upon was of the eclipses of Jupiter’s satellites.

As there are four satellites and as the plane of their orbits is nearly
the same as that of the planet itself, eclipses are frequent. The
plan proposed the observation of all these eclipses visible during a
revolution of Jupiter around the sun, a period of about 12 years. The
work was begun June 23, 1878, and has been regularly pursued. The final
result will be of the highest value in that, among its utilities it
will permit a new and independent computation to be made of the earth’s
distance from the sun, which distance is a prime factor in theoretical
astronomy.

Computations hitherto made, based upon data derived from these
eclipses, are not authoritative, because of disagreements among
different observers using different telescopes, and because of defects
in the method of observation.

The director’s report for 1878 says: “Errors of this kind are much
lessened by photometric observations of the satellites as they
gradually enter or emerge from the shadow of Jupiter, using the planet
itself or another satellite as a standard. Each comparison thus
obtained gives an independent determination of the time of the eclipse,
free from the errors due to the condition of the air or the power of
the telescope employed and less likely to be affected by personal
equation than the observation of a disappearance or a reappearance.
By the ordinary method an observation during twilight can have little
value, while good photometric observations may be made as well then as
at any other time. It is even possible to make them before sunset.”

In 1879 a work of magnitude was begun—the photometric observation
of all stars down to those of the sixth magnitude visible in this
latitude. For greater facility, and particularly to avoid loss of time
in identifying stars of small magnitude, it was decided to make a new
departure in method and in construction of an instrument. The new
instrument was called the meridian photometer, and stars were observed
by it only when near the meridian. The position of any star being well
known, the time of its appearance in the field of the telescope could
be foreseen.

Each that was desired for a particular night had, therefore, only to
be waited for, not sought for. The original instrument consisted of a
fixed horizontal telescope pointed west and having two objectives.

The light of the pole star, which was taken for the standard or unit of
measurement, was reflected by a prism into one object glass, and that
of the star to be measured into the other. The light of the brighter
star was then reduced to exactly that of the fainter by the turning of
a screw having a register attached. The indication of the register gave
the measure, which was confirmed by repeated observations. Telescopes
mounted in the ordinary way continued to be used in other branches of
photometric work.

[Illustration: HARVARD OBSERVING STATION AT WILLOWS, CAL., JANUARY 1,
1889.]

The photometric survey of the sixth magnitude and brighter stars was
completed Aug. 25, 1881. In 1882 a new and more powerful meridian
instrument was constructed and a photometric survey of a list of about
21,000 stars, from the sixth to the ninth magnitude, was entered
upon. This work was finished Sept. 29, 1888, and soon afterwards the
instrument, with others, was sent to Peru in charge of Mr. S. I. Bailey
of the observatory corps, where, May 11, 1889, a corresponding survey
of the stars, from the first to the ninth magnitude, inclusive,
between 30° south and the southern pole, was begun. Thus the facts
relating to all the stars in the sky of these classifications will be
embodied in the final result.

The record, which will comprise several volumes, one or more of which
have already been published, will have an identity throughout as
respects the method, the instrument, and the unit of measurement. It
will be authoritative as a text book or series of text books, and will
enhance the value for reference, and comparison of various records of
the light of stars, both those of modern and ancient date.

The successful working of the two meridian photometers led to the
construction of one still more powerful, having an aperture of 12
inches. The first was of 1½ inch aperture, and the second of four
inches.

The three differ somewhat in mechanism, but are the same in principle.
The 12-inch is called by distinction the “horizontal telescope.” It
will be available in case a photometric survey of stars of fainter
magnitudes shall be undertaken, but its use is not limited to
photometry.

In 1879, a photometer was devised for measuring the light of nebulæ,
thus applying to these objects and to stars the same unit and scale. In
1881, photometric observations of certain bright parts of the moon,
were made for the Selenographical Society of England, the particular
parts being selected by that society. It thus was shown that the
lunar scale of light in common use may be closely expressed in terms
of stellar magnitude, each degree of the lunar scale answering to
six-tenths of a magnitude. Photometry has been very extensively applied
at Harvard in study of variable stars.

A history of any department of practical astronomy, written from the
point of view of a mechanician, could hardly fail to be of interest.
Among the curious experiences at Harvard in the line of photometry is
one which illustrates this point, and, at the same time, indicates the
refinements in observation which are resorted to, and demonstrates one
of the utilities of the photometric method.

[Illustration: HARVARD OBSERVING STATION IN PERU.]

In 1877 announcement was made of the discovery at Washington of two
satellites of the planet Mars. The Harvard telescope being applied
they were after a little effort descried as two faint points of light,
showing no visible disks. To ascertain the diameter of each satellite
might therefore seem impossible: but it was done, approximately, by the
photometric method.

The mechanical problem was to reduce the light of the planet as seen in
the telescope to an equality with the light of one of the satellites
as thus seen. Five or six different mechanics were employed to drill
in a piece of metal a hole, making a true circle, and small enough to
produce the equality sought for by sufficiently diminishing the light
of the planet. It may be remarked that one of those who succeeded best
had already, for his own purposes, managed to drill a hole, lengthwise,
through a fine cambric needle, making a steel tube of it.

What he made for Prof. Pickering was a hole in a steel plate, the
diameter of which was one eighteen hundredth (1-1800) of an inch. It
was so nearly circular that the various diameters, including errors of
measurement, only differed one one hundred thousandth (1-100,000) of an
inch.

Other mechanical devices were resorted to for corroboration, and the
results reached were that the diameter of one of the satellites is
about six miles, and that of the other about seven miles. They are the
smallest known in the solar system.

The availability of the spectroscope in astronomy had early been
appreciated by the profession. In experiments in this line it had been
found that a classification of the nebulæ might be made upon the basis
of their spectra. In 1880 the study was carried a stage further at
Harvard in ascertaining by the spectroscope that certain faint objects,
which, by direct vision, had been judged to be stars, are in fact
nebulæ. In 1881, it was found that the spectroscope is serviceable in
the discovery of variable stars. Thus incited, a new instrument was
imported from London, but it did not prove satisfactory.

Nothing of importance appears to have been done in this department
thereafter until 1886, when the proposition of Mrs. Draper opened the
way to investigation of spectra by aid of photography. For this the
11-inch photographic telescope, which had been used by Dr. Draper,
was loaned by Mrs. Draper, who also met the expense of a new mounting
and a special observatory building. A beginning was made with an
eight-inch instrument, known as the Bache telescope. It is of the
pattern described as the “doublet,” and offers the advantage of a
large field of view. With it the spectra of about 10,500 stars of the
sixth magnitude and brighter, between the pole and 25° south, were
photographed before the close of the year 1888.

The instrument was then sent to Peru, where a like survey of the
Southern sky is in progress. Spectroscopic observations of the brighter
stars have been continued at Cambridge with the 11-inch Draper
telescope and of fainter stars with an 8-inch doublet similar to the
Bache instrument. In this work it was found that by giving a certain
chemical stain to the photographic plate the yellow and green portions
of the spectrum of even the fainter stars can profitably be studied.

Furthermore, what seems incredible at first thought, it appears to be
demonstrated that the components of binary stars whose juxtaposition
does not permit them to be separated in any telescope, may, by
spectroscopic photography, be shown to be in revolution about each
other. Two or more such objects have been found in which the changes
regularly succeeding in the lines of the spectrum not only prove that
the components are in motion, but permit the period of revolution to be
determined.

Prior to 1883 photography is mentioned in the annual reports of the
present director only as incidental to other work. In that year a
systematic investigation was undertaken, having among other objects
in view, the construction of a photographic map of the whole heavens.
An early application of photography in this investigation was in the
direction of determining the color of stars, measuring their brightness
by an independent method, picturing their spectra, exhibiting the
effect of atmospheric absorption of light in a series of plates
covering the period of a year, and ascertaining by images of stars
trailed upon the plate, the clearness and steadiness of the atmosphere.

In 1887 the Boyden fund being available, the first step was taken in
the important enterprise of giving a continental expansion to the work
of the observatory. The aim of the testator in making his bequest
could well be furthered in conducting observations simultaneously
in photometry, spectroscopy and photography. In following up the
project, the Draper memorial funds appear also to have been available
to a considerable extent in the two latter methods of observation.
Experimental stations were established in Colorado in the summer of
1887 on mountain peaks of 14,000, 11,000 and 6000 feet in height,
respectively, and the meteorological conditions, including the
transparency and steadiness of the upper atmosphere, were duly tested.

This investigation was continued at the expense of the Boyden fund
during the following winter by local observers whose stations were at
considerable height.

In 1889 the movement was further extended by establishing an
observatory on a peak about 6500 feet high in Peru, 25 or 30 miles
distant from the sea coast and the city of Lima. Local official
sanction was given to naming the peak, “Monte Harvard.” About the
same time other observers of the Harvard corps set up an experimental
observatory on Mt. Wilson, 6000 feet high, in Southern California. The
station is about 30 miles from the sea coast and somewhat less from the
city of Los Angeles.

The experimental purpose is the same as in Colorado, and looks to
the ultimate establishment of a permanent observatory as a branch of
the Harvard institution at some favorable point where the superior
atmospheric conditions of the Pacific mountain regions can be had. In
the special direction of picturing celestial objects at Mt. Wilson
remarkable photographic results are already possessed at Cambridge in
plates showing lunar surfaces, Saturn’s rings, Jupiter’s belts and the
most brilliant of the nebulæ. That among them which is of the greatest
scientific interest, as being a novelty, is the picture on a negative
plate of the great spiral nebula of Orion. It is a Harvard discovery by
the photographic method, and is quite other than that heretofore known
as the great nebula in Orion. That is an object having a span of about
half a degree. The new great nebula has a span of nearly 17 degrees;
its outline includes all the stars of the constellation, and it is too
faint an object to be discerned by the naked eye.

It is one of the principal advantages of the photographic method in
astronomical work that the sensitive plate will denote objects which
the eye reinforced by a telescope of any power cannot detect. The
great nebula thus discovered is within reach of the telescope, but its
dimensions are so much larger than the field of the telescope, and its
outline so faint, that its true character would not thus originally be
apprehended.

Photography at Cambridge has already produced several series of
plates, each plate covering a section of the northern sky, the whole
of which when perfected and collated will be a self-recorded, and so,
indisputable atlas, showing the position of all stars down to those of
the 11th magnitude. It will be an atlas in sheets of glass, and frailer
in some respects than if composed of sheets of paper. But for study
of the science the glass is better than any product of the engraver’s
art, and better than any sun picture printed by the plate itself.
Indeed, it is one of the triumphs of the photographic method that a
perfect photographic negative discloses more to the student than does
a telescopic view of that area of the sky of which the photograph is a
copy. Astronomical research is now constantly made at the observatory
in this manner, and with results equal to or better than those reached
by former methods.

Celestial objects are thus originally discovered and the positions
of familiar objects remeasured or otherwise compared, and this work
might be continued throughout the whole 24 hours were it so desired,
regardless of the glare of the sun by day or of impenetrable clouds by
night.

The work in progress in Peru will give other series of plates offering
equal facilities for the study at Cambridge of that part of the sky
which is beyond our southern horizon. Some of the results which these
extensive investigations of the light, the spectra and the positions
of the stars will yield will anticipate the doings of other great
observatories of the world. But there is no necessary limit at stars of
the magnitudes named; there will remain other worlds to conquer.

A special encouragement to new enterprises at Harvard is in the
munificent gift of $50,000, made within the year past by Miss Catherine
W. Bruce of New York for the construction of a telescope of 24 inches
aperture, to be used in photography. A contract for this instrument has
been made. It is intended that its first use shall be to photograph
maps of the fainter stars, and it is hoped that those as faint as the
16th magnitude can thus be represented. The basis of this sanguine
forecast is the fact that with an eight-inch telescope of the pattern
of the proposed 24-inch, and an exposure of the plate for one hour,
twice as many stars are photographed as are visible with a telescope
of 15 inches aperture. Prof. Pickering received the honorary degree of
A.M. from Harvard in 1880, and that of LL.D. from the University of
California in 1886, and from the University of Michigan in 1887. Like
his predecessor, Prof. G. P. Bond, he has been honored by the Royal
Astronomical Society in the bestowal of its gold medal.

The several investigations of chief importance which are now in
progress at Harvard College Observatory have already been mentioned
as part of the record of the half-century past. They also go into the
record with which the second half-century now begins. As such they
may be briefly recapitulated, viz.: The survey, for the purposes of
the great European standard catalogue known as the “Astronomische
Gessellschaft,” of the zone between 9° 50′ south and 14° 10′ south; the
photometric, spectroscopic, and photographic special surveys making in
south latitude to complete like surveys hitherto made at Cambridge,
extending to about 30° south; the systematic work in photography,
which includes much classifiable as spectroscopy, carried on both at
Cambridge and in Peru as the Draper Memorial work: other systematic
work of like importance done under the special restrictions of the
Boyden fund; and what perhaps may be called the orbital observations of
eclipses of Jupiter’s satellites.

That planet has now nearly completed its circuit around the sun, and
the last of its satellite eclipses to be observed will occur on Dec.
17 ensuing. During the period of 12 years about 450 of these eclipses
have been observed and recorded. Perhaps as many others for which
preparations were made at the observatory, passed unseen, because of
interposing clouds. Except to an expert these figures give no hint
of the magnitude of the work. All that need here be said is that in
its completed form it will be one of the great achievements of the
observatory.

The enumeration of these unfinished works and those completed, which
has now been made, will have fulfilled its purpose if it shall have
impressed upon the mind of the general reader the fact, with which it
is presumable everybody is somewhat familiar, that a great oak has
grown from the little acorn planted on Harvard College campus 50 years
ago.



  Transcriber’s Notes:
   - Text enclosed by underscores is in italics (_italics_).
   - Blank pages have been removed.
   - Silently corrected typographical errors.





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