Tuttles of Harvard College Observatory part 1

ISSN 1740-3677

Issue 6

January 2012

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2 Issue 6, January 2012 The Antiquarian Astronomer

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The Cover illustration:

A GREAT MODERN OBSERVATORY

The Century Magazine, June 1897, p. 299

ur cover illustration first appeared in an

article by Mabel Todd Loomis titled ‘A Great

Modern Observatory’ in The Century Mag-

azine, June 1897. Forty years after Horace P. Tuttle

arrived at the Harvard Observatory; this was perhaps

the only vantage point preserving the illusion that little

has changed. As always the Sun has risen and the

astronomer begins his stroll homeward, alone in thou-

ghts of last night’s work. But how that work has

evolved! In 1897 the Great Equatorial still rests under

its massive copper dome, but no longer is it Harvard’s

principle instrument, and no longer does it measure

astrometric positions. Under the directorship of E.C.

Pickering, it has been given over to ‘the new astron-

omy’, the measurement of physical properties of the

heavenly bodies: analyzing the light of variable stars

and of the moons of Jupiter. The East balcony no

longer supports an astronomer and comet seeker, and

four years earlier a massive fireproof addition houses

the seventy thousand photographic plates of stellar

spectra and photographic magnitudes produced in that

past decade that ‘may take the place of the sky itself’.

The new Bruce photographic telescope has been pho-

tographing southern stars from 20,000 feet at

Arequipa, Peru; no other observatory could claim

dual-hemisphere programmes ‘harmonious’ under one

director.

‘This conjunction of photography with the study of

stars obliterates the favourite popular vision of the

typical astronomer, up all hours with eye constantly at

a great “optic tube”’, wrote Mrs. Loomis. ‘If the at-

mosphere be lower than freezing, or even a New

England zero, romantic imagination insists that his

heart must be amply warmed by his heavenly

enthusiasm. But the elimination of personality makes

the records of astronomy indisputable, and renders its

pursuit more practical, not to say more comfortable…’

Now a full century past Mabel Loomis, we desire

to return to the romantic and personal era of visual

astronomy at the Harvard College Observatory, to put

our own eye to the optic tube.

O

Copyright© 2011 Society for the History of Astronomy

Issue 6, January 2012 The Antiquarian Astronomer

74

The Tuttles of Harvard College Observatory: 1850 – 1862

Richard E. Schmidt

[email protected]

U.S. Naval Observatory, Washington, DC

Today it is difficult to imagine the degree of human effort that

nineteenth-century astronomy required. Before the advent of photo-

graphic techniques and mechanical calculators, visual astrometry of

stellar and solar system objects relied upon the quality of the observer’s

observational and computational skills as much upon his tolerance of

harsh observing conditions. In the 1850s, the new Harvard College

Observatory was about to become America’s premier centre for

astronomy. With meagre funding Harvard would need quality skilled

labour and fascinated patrons. The arrival of a few great comets, and

two brothers named Tuttle, would amply fill that need.

Introduction

he brothers Charles Wesley Tuttle (1829-

1881) and Horace Parnell Tuttle (1837-1923)

are among the largely forgotten pioneers of

American astronomy of the mid-nineteenth century.

As Harvard students of William Cranch Bond (1789-

1859) and his son George Phillips Bond (1825-1865),

the Tuttles helped provide the blunt observational and

computational strength that would fortify Harvard’s

role as the preeminent educator of American astron-

omers. Both started astronomical careers as comet

seekers; among the discoveries of H.P. Tuttle are two

minor planets, 66 Maja and 73 Klytia, and the parent

comets of three meteor showers, the Ursids, Perseids,

and Leonids.

Comet seeking brought real benefits to the Har-

vard College Observatory. It provided state of the art

observational data for astronomical research, as

demonstrated in the remarkable account of the great

Donati’s comet of 1858 produced by George Phillips

Bond. It strengthened Harvard’s bonds with the Am-

T

Fig. 1 Harvard College Observatory, south elevation.

Annals of the Astronomical Observatory of Harvard College, 8

(Cambridge, MA: John Wilson and son, 1876)


78

In 1849 C.W. Tuttle was working in a carpenter

shop near the Safford home. Tuttle’s friendship with

Safford led to the former’s return visit to the Harvard

College Observatory, as Safford later related:

In a few days I went with [Tuttle] to the Obser-

vatory, and introduced him to the Bonds. They

were pleased with him, and shortly after asked me

if he would not be a good man to come to the Ob-

servatory on a small stipend, – I think five hundred

dollars yearly, – and be generally useful in the

work of the Observatory... He was in fact invited

to accept the position – I suppose provisionally –

before he went “as a student” and received the

appointment from the Corporation, when it was

found that he was practically ready for a fixed

position. His first position was in fact that of an

‘Elève,’ as it is called in some places abroad, – a

highly promising learner under pay.23

In July 1850 Tuttle’s ideal vocation became reality as

he began study under the two Bonds. The long nights

Tuttle had spent preparing for this opportunity – both

at his home studies, and with his own telescope – were

well spent; his nascent ability surprised W.C. Bond.24

Formal coursework in practical astronomy was supp-

lemented with training on the transits, the equatorials,

and the measurement instruments. Tuttle would learn

the techniques of visual astrometry, as well as the

challenge of computing orbital elements and ephem-

erides using spherical trigonometry and the math-

ematics of logarithms in this age without calculators.

The computation of parabolic elements from three

observations would take several hours of careful

pencil work!

Under the tutelage of William Cranch Bond and

his sons George Phillips and Richard F. Bond, C.W.

Tuttle progressed so rapidly in his studies that in Feb-

ruary 1851, the Board of Overseers nominated him for

appointment as ‘Second Assistant in the Observatory’.

The ‘First Assistant in the Observatory’ was at that

time George P. Bond. The Dover Enquirer, under the

title ‘Genius Rewarded’, lauded its local boy:

Mr. Tuttle is only 21 years of age, and is a Dover

boy. For two or three years past he worked as an

apprentice to the house carpenter’s business with

Mr. J.W. Tuttle of this town, and has had no ad-

vantages except those found in our common town

schools, and his own hard study after working

hours.25

Saturn

One could hardly imagine a greater thrill for a novice

astronomer than to be given the keys to one of the

largest telescopes in the world, to be engaged in

viewing the rings of Saturn as C.W. Tuttle was soon

to be. In 1848 Saturn’s rings turned edgewise to the

Earth. Two years later the rings began to unfold once

again, revealing unparalleled views through the Har-

vard Great Equatorial. In November 1850 the Bonds

were puzzling over dark shadows seen inside the in-

ner ‘B’ ring of Saturn. The two bright rings appeared

to leave a shadow of sunlight both below and above

the rings where they crossed in front of the ball of the

planet. From the Harvard Annals:

On the evening of the 15th [of November] the idea

was first suggested by Mr. Tuttle of explaining the

penumbral light bordering the interior edge of the

bright ring outside of the ball, as well as the dusky

line crossing the disc on the side of the ring

opposite to that where its shadow was projected on

the ball, by referring both phenomena to the

existence of an interior dusky ring, now first

recognized as forming part of the system of Saturn.

This explanation needed only to be proposed to

insure its immediate acceptance as the true and

only satisfactory solution of the singular appear-

ances which the view of Saturn had presented

during the past season, and which we had pre-

viously been unable to account for.26

Here was the first recognition of a third ring of

Saturn, the ‘C’ ring. Within weeks it was inde-

pendently discovered by William Rutter Dawes in

England.27 Not since the Bond’s independent

discovery of Saturn’s moon Hyperion in 1848 had the

Great Refractor so contributed to making headlines in

planetary astronomy. On occasions of superb seeing,

the fifteen-inch refractor was capable of providing

truly astonishing detail. On 20 October 1851 Tuttle

observed subdivisions in the ‘B’ ring:

Powers 141 and 861.28 W. C. B[ond] comes up to

look at Saturn – we found it excellent seeing –

Saturn seldom looks finer – went down and invited

[Richard F. Bond] and Miss Selina [Bond] to come

up and see it. They returned to the dome with me.

There is no mistake but the inner bright ring is

minutely subdivided into a great number of small

rings. The divisions commence on the inside

nexth [sic] new ring and extend over about two

thirds of the inner bright ring. These divisions are

quite apparent – with a high power.29

For two weeks beginning 22 October 1852 G.P. Bond

and C.W. Tuttle observed the shadow of the ball to

fall on the rings on both the preceding and following

sides of the planet. ‘What can this mean?’ Tuttle

wondered.30

The ‘dusky ring’ was so transparent that on 15

December 1853 C.W. Tuttle observed (with a power

79 The Antiquarian Astronomer Issue 6, January 2012

of 401) the ball of Saturn visible through the

translucent and ‘reddish or copper-colored’ ring.31

Comet seeking

Observing with the Great Equatorial was the height

of astronomical luxury. Shielded from cold winds by

the dome, you sat upon velvet cushions with hand

cranks to raise and lower your seat and to move you

around the dome. Aided by fine setting circles, a

superb clock drive, perhaps an assistant behind a dark

curtain in an alcove of the dome recording times and

notes, and with twenty-three feet of telescope

powering your vision, this was comfortable ob-

serving. Absolutely at the other end of the spectrum

was the chore that befell C.W. Tuttle beginning 30

October 1850: ‘comet seeking’. Harvard owed a debt

of fame to comets, and W.C. Bond was intent on

repaying it. Since 1848 it had been the duty of the

Assistant Observer ‘to complete the sweep of the wh-

ole visible heavens once every month’.32 The Obser-

vatory had been presented with two small ‘comet

seekers’ named for their patrons, the 2.5-inch

‘Quincy’ comet seeker by Dollond, and the four-inch

f/8 ‘Bowditch’ comet seeker by Merz. These were

kept in alcoves in the great dome. Out of the east,

west, and south walls of the dome hung wrought-iron

balconies, four by six feet in size, and elevated some

thirty feet above the ground, onto which the comet

seekers would be carried. Here blew cold winds in-

deed! For the seventeen years from 1841 to 1857, the

mean temperature from December to March on the

external thermometer at Harvard College Observatory

was well below freezing.33

Comet seeking has always been an exceedingly

tedious process. Unlike planets, comets do not con-

fine themselves to the ecliptic, and can first appear

anywhere in the sky. New-found comets are generally

small and faint, requiring clear nights in the absence

of strong moonlight and twilight. The field of view of

the Bowditch comet seeker at low power (12x) was 2º

8'. The entire sky would comprise over 11,500 fields

of view. Within those fields were numerous comet-

impostors: star clusters, nebulae, and galaxies. C.W.

Tuttle described comet seeking in an 1858 newspaper

article:

Few persons are aware of the patience and labor

exercised by the astronomer in making discoveries

of this kind. It requires several years’ study and

practice to qualify one to discover a telescopic

comet. It is undoubtedly very easy to look at a

comet already visible to the naked eye in the

heavens; but when it is required to discover an

unknown one, wandering in its “long travel of a

thousand years” in the profound abyss of space,

the labor then becomes truly prodigious. The

amount of physical suffering occasioned by

exposure to all kinds of temperature, the bending

and twisting of the body when examining near the

zenith, and the constant strain of the eye, cannot be

fully understood and appreciated by one

unacquainted with an astronomer’s life.

The astronomer, with his telescope, begins at the

going down of the sun, and examines, in zones,

with the utmost care and vigilance, the starry vault,

and continues till the “circling hours” bring the sun

to the eastern horizon, when star and comet fade

from his view. It requires several nights to comp-

lete a thorough survey of the heavens; and often

these nights do not follow in succession, being

interrupted by the full moon, by clouds, auroras,

Fig. 7 Saturn’s dusky ring, December 15 1853, Harvard College Observatory. Annals of the Astronomical Observatory of

Harvard College, 2 (Cambridge, MA: John

Wilson and son, 1857-1867) (1), p. 79.

Fig. 8 North balcony of the Great Equatorial, 2010. Photograph by the author.


80

and by various other meteorological phenomena.

He is frequently vexed by passing clouds, fleeting

through the midnight sky, and strong and chilly

breezes of the night. His labors are continued

throughout the year, and his unwearied exertions

do not slacken during the long wintry nights, when

the frozen particles of snow and ice, driven before

the northern blast, cause the stars to sparkle with

unusual lustre, and his breath to congeal on the

eye-piece of the telescope. It frequently happens

that his labors are not crowned with a discovery

until after several years search.34

The Harvard comet seekers were nothing if not per-

sistent. George P. Bond had discovered eleven comets

by 1851, of which nine were telescopic. Only the great

Charles Messier at Paris had found more. Yet all but

one of G.P. Bond’s comets were first discovered by

European astronomers.35 C.W. Tuttle began comet

seeking on 30 October 1850:

Mr. Tuttle swept East of the Meridian from 7h30m

to 9h PM all from pole to the horizon about to

Gemini in the East & the AR [right ascension] of

Fomalhaut. Found a nebulous object in S. Dec.

-28º AR 0h 40m. [Subsequently added:] Found to

be a cluster next night.36

The Bowditch comet seeker was at that time a

German equatorial without an eyepiece diagonal, and

it could not be used on the meridian near the zenith.

G.P. Bond noted on 27 December 1850, ‘I shall never

feel sure of not missing a comet until we get the new

plan of a Comet Seeker’. Harvard kept a large celest-

ial globe in the dome on which observers would mark

newly found or suspicious nebulous objects. In

addition, the Observatory maintained a ‘Catalogue of

Nebulae’ and a comet-sweeping journal in which new

objects would be recorded.

For C.W. Tuttle, months of fruitless searching cul-

minated in the ‘unlucky night’ of 14 August 1851

when he failed to recognize that he had found a comet.

On 19 August he wrote:

[Today] No. 768 [Astronomische Nachrichten] has

arrived and on opening it was surprised to find a

circular announcing the discovery of a Comet by

Brorsen on the first of Aug.37 Indeed, must I search

the heavens in vain? On the [evening] of Aug. 14 .

. . I swept in that vicinity where the Comet was

situated, and distinctly recollect of finding an

object which I suspected might be a Comet, near

where this must have been. The case is simply

this. I went to the globe and found a nebula

marked down near the place, and what is not a

little singular, the place where I found the nebula

on the globe was within the circle where the maker

had placed his name and authority. Thinking as it

was in such a place there might be some

uncertainty about the location of the [nebula], I

give it no more attention after seeing it on the

globe somewhere near the place. Further than this,

I swept hastily because I wished to finish that side

before the moon rose.

Upon the whole, it is a gross piece of carelessness

on my part. Having just been at the comet-seeker

and found the comet I am strongly impressed that

its countenance is not new; but resembles the

famous [nebula] of the 14th. I do not care a snap

about it, only I think if there was one as large as

the full moon, it would steer clear of me. The

comet appears pretty bright in the Comet Seeker.

Should have taken an observation [with the Great

Equatorial], but the micrometer was off the Great

Equatorial for Mr. Whipple, who is going to

daguerreotype the Moon towards morning.38 I had

begun to Comet-seek on the East balcony when I

for some reason or other, had occasion to go down

to the computing room and saw the Nachrichten

lying on the table inside of which was the circular.

I hastened up stairs and drew the Comet seeker

over on the West balcony, and after waiting some-

Fig. 9 The Bowditch comet seeker, circa 1890. Compare with Fig. 13. Harvard University Archives, UAV 630.271 (E4722).


time for some clouds to move away, I with a mix-

ture of pain and pleasure began to search for it. In

a few minutes it came into the field of the Comet

Seeker.

After this attempted to sweep for nearly two hours

but my mind was so agitated that it did not amount

to much.39

W.C. Bond and C.W. Tuttle made observations of

Brorsen’s comet on 23, 26, and 29 August. Tuttle

computed a parabolic orbit that was published in the

Astronomical Journal.40

On 27 August Tuttle noted the strain on his eyes

following a complete sweep from the West balcony.

‘My eyes had become so fatigued that I was

frequently compelled to halt – but not withstanding all

this, pushed forward and succeeded in sweeping over

the eastern sky…’.41

Tuttle would continue to sweep as often as weather

allowed. ‘No Messier ever swept with greater care

and higher hopes than I have…’, he remarked on 22

October 1851. But one month later, Brorsen at Sen-

ftenberg beat him again. ‘Most painful news!’ Tuttle

wrote:

Now Col. Brorsen you have monopolized the

heavens pretty well this year, and if you succeed so

well again, I miss my guess. Our comet seeker has

been rendered a [sic] considerably more easy for

sweeping by the addition of a new diagonal eye-

piece, and will hereafter enter the field under more

powerful auspices and favourable circumstances.42

G.P. Bond independently discovered ‘the first comet

of 1852’ on 19 May, and C.W. Tuttle computed

elements of its orbit.43 But it would be another ten

months before C.W. Tuttle would make his own in-

dependent discovery. The strain of observing was tak-

ing a toll on Tuttle’s vision; he was advised to take

time off for rest. In July 1852 he retired to Dover,

then booked a stay at the Appledore House, Isle of

Shoals, Maine, where ‘invalids who wish for an

equable temperature of the atmosphere, for purity of

air, and a total absence of all dust and offensive

odours, will do well to make this their residence du-

ring the hot and unhealthy months.’44 After a week of

rest, he set out to visit the White Mountains of New

Hampshire, making a horseback ascent of Mount

Washington. Tuttle wished to compare the brightness

of the stars and planets on the summit (1,900 m) with

their brightness at sea level, and ‘also to witness the

sublime spectacle of a sunrise and sunset’. But before

sunset clouds enveloped the summit. ‘A night-cap had

been set on the head of Mt. Washington, and there

remained till break of day, when it was silently and

quietly withdrawn, to give me, what I much longed

for, a sunrise, the most magnificent spectacle that I

ever expect to witness’.45

The first comet of 1853 appeared as a very com-

pact object five degrees south preceding the star Rigel.

C.W. Tuttle wrote in the comet-seeking log:

March 8 P.M. Half past 8 o’clock went into the

dome and out on the balcony, where the air felt

quite comfortable and the heavens looked inviting .

. . thought it worthwhile to sweep a “bit”. Drew

the comet-seeker out and directed it at random

(pretty low down in the west horizon) and began to

“sweep” up to the meridian. Did not proceed far

when a “nebelflecke” [nebula] of unusual brill-

iancy came into the field. It had decidedly a starry

appearance. Went to the globe and found nothing

there to indicate its existence, then down stairs and

got the Comet-book (this book) and here likewise

found no mention of it.

However, its starry appearance seemed so decided

that for a few moments it was doubtful whether it

was worth the “powder” to turn the Great Equat-

orial on it, or not.

Finally it was thought that the labor might as well

be spent on examining it, as in fruitless sweeping.

Pulled open the shutters with little expectation of

seeing anything but a fine cluster of stars. Brought

the telescope to bear on it, but not the slightest

evidence of resolution. Procul! O Procul! was the

first thing that suggested itself. 46 Eh bien! measure

it! Such an object is worthy of being catalogued,

and may save some zealous comet-hunter a great

deal of labor hereafter. Illuminated the wires and

at the second passage through the field there was a

certain evidence of a motion towards the north.

It was from that motion that Tuttle knew he had found

a comet! From its positions, Tuttle computed and

published orbital elements.47 Cambridge weather was

most cooperative beginning April 14, when obser-

vations of the comet with the Great Equatorial were

obtained on twenty-one consecutive nights. But weeks

later, word arrived that Tuttle’s comet had a prior

claim of discovery. Tuttle wrote:

The above comet was discovered on the sixth of

March at the Observatory of the Collegio Romano

at Rome by Signor [Father Angelo] Secchi – and I

conclude that “His sore labors ne’er divide the

Sunday from the week” by his having found it on

that day. It was also discovered by Prof. [Kaspar]

Schweizer of Moscow...and by Dr.[Wilhelm] Hart-

wig of Leipzig...so it is safe!48

The New York Times took note of the light-hearted

competition in the heavens:


system of treatment failed to relieve him, and he was

obliged to suspend observing altogether. After some

delay, finding no relief for his eyes, he reluctantly

resigned the position of Assistant Observer, a position

which had been the aim of his life to attain’.54 W.C.

Bond, in his annual report to the visiting committee,

wrote:

Mr. C.W. Tuttle found himself under the necessity

of resigning his connection with the Observatory,

in consequence of the failure of his eyesight, a

circumstance much to be regretted, as he partici-

pated faithfully and ardently in our pursuits, and

had proved an eminently capable assistant during

the four years of his engagement. A journey to the

West, affording relaxation from an undue exertion

of his eyes, has so far arrested the progress of the

malady as to enable him partially to resume his du-

ties as an assistant, while at the same time he has

entered himself as a law student at Dane Hall.55

In July 1854, C.W. Tuttle was awarded the honorary

degree of Master of Arts.56 He entered the junior class

of the Harvard Law School at the second term 1854-

55, graduating in two terms and was awarded a law

diploma on 8 August 1855.57

The Chronometer Expedition of 1855

The Harvard Chronometer Expeditions, for the

purpose of establishing a longitude reference point in

the United States relative to the Greenwich Observa-

tory, were carried out under contract to the United

States Coast Survey in the years 1849, 1850, 1851 and

1855. The principle was simple: observe the time of

transit of a star on each side of the Atlantic, using the

same clock. The difference of longitude was given by

the difference in observed time of transit. The details

involved determining clock rates, and using many

clocks on multiple trips across the Atlantic. In 1855

an ensemble of forty-two marine chronometers

travelled six times across the Atlantic between Boston

and Liverpool on the steamships America, Asia, and

Africa, sailing eighteen thousand miles without incid-

ent.58 In charge of the expedition, was Phillip Sydney

Coolidge (1830-1863), a grandson of Thomas Jeffer-

son who became an assistant at the Observatory in

1854, where he was known for his planetary

observations and his work on the Zone Catalogues.

(Late in 1857 Coolidge would leave Harvard to assist

Andrew Talcott in the survey of the Veracruz-Mexico

City railway line, after which he decided to stay and

fight with the Liberals in the Mexican revolution.

Soon he was captured and nearly executed as a

‘fillibuster’.59 Fast diplomacy by the American

Minister effected his escape and safe return.) Richard

F. Bond, son of William Cranch Bond, and P.S.

Coolidge sailed out of Boston on the America on 6

June, arriving at Liverpool after eleven days. They

were detained in England for one month awaiting the

arrival of a larger steamer, the new Cunard steamer

Asia, which left Liverpool on 20 July, arriving back in

Boston on 4 August. C.W. Tuttle and P.S. Coolidge

sailed with the chronometers on the Asia, leaving

Boston on 14 August and docking at Liverpool on 26

August. The clocks were carefully conveyed to the

Liverpool Observatory at Waterloo Dock where

chronometers were rated and transit observations

made. There was at that time no telegraph connection

between the Liverpool and Greenwich Observatories.

W.C. Bond had offered to establish such a link with

Coast Survey funds, but the proposal was rejected.60

On the first of September the Asia’s sister ship Africa

carried them back to Boston, making the return in

eleven days. This most successful of the Harvard

chronometer expeditions established a difference in

longitude of 4h 44m 32s between the Harvard College

Observatory and the Royal Greenwich Observatory.

Upon his return from England Charles Tuttle

entered the law office of the Hon. Harvey Jewell, of

Boston, where he completed his law studies. In May

1856, he was admitted to the Massachusetts bar. The

author Harriet Prescott Spofford, wife of C.W. Tut-

tle’s law partner Richard S. Spofford, met Tuttle in

1859:

When I first met Charles, the impression that he

made upon me had a strange romance about it. . . .

[We] all knew that he had been compelled to

abandon the aim of his life and the dream of his

heart, owing to threatened blindness, and to open a

new path for himself; and that fact gave him a sort

of heroic cast in our thoughts. I never divested him

of a certain poetry that hung about him then; he

seemed to belong to the region of great unknown

equations, to be part of the world of stars out of

which he had come into our more common and

prosaic life.

I shall never forget a night that I spent with him in

the company of my husband, – who was long in

close professional and family relationship with

him, cherishing between them a most tender

attachment, – in the Cambridge Observatory look-

ing through the immense telescope there. It would

have been no different had we gone into the realm

of unreal things, and among the arcane of magic,

while that great engine tipped at the touch of the

finger, while the swift sliding stars shot like met-

eors over the field before the clockwork was

attached, while the iron dome turned and cracked


and his wife, Angeline.66 The Halls could barely make

due on observer’s pay, and at one time G.P. Bond

pleaded with the Observatory Board of Visitors for

relief:

Their annual compensation averages less than

$500 a year. I am ashamed to have them remain

for such a miserable pittance, but do not know how

to keep up the work expected from the observatory

without them.67

The first recorded observation by H.P. Tuttle was of

an occultation of Spica on 12 March 1857.68 The

Observatory timed occultations that could be observed

at multiple observatories for the improvement of the

lunar theory, the profile of the edge of the Moon, and

for longitude determination.69 For this occultation of

Spica the Bonds enlisted every hand and every avail-

able telescope: George P. Bond on the ‘23-foot equa-

torial’ [the Great Equatorial], Sydney Coolidge with

the ‘4-ft. refractor’ [the finder of the Great Equator-

ial], Robert Treat Paine, on the ’54-inch [focal length]

refractor’, Richard F. Bond with the ‘Lerebours 5-ft.

refractor’, and H.P. Tuttle with the ‘Christoph

reflector’.70Times of immersion and emersion were

recorded to tenths of seconds by interpolating the

beats of one and two second chronometers.

Occultations of the Pleiades were observed on 2

November 1857 (Coolidge, Tuttle, Hall), 27 Decem-

ber 1857 (Tuttle), 18 January 1858 (Tuttle, G.P.

Bond), 19 March 1858 (G.P. Bond, R.T. Paine,

Tuttle), 20 November 1860 (Tuttle), and 24 December

1860 (Tuttle, G.P. Bond). For the last of these

A chart of the Pleiades, on the stereographic

projection, was constructed by H.P.T., and the

moon’s apparent place for 5 different hours was

computed and projected on the chart. From these

were obtained the times of [disappearance and

reappearance] of 27 stars of the group.71

Eclipse observations at Harvard College

Observatory

Precise timing of eclipse contact events provided

valuable insight into the lunar theory. Peter Hansen’s

‘Lunar Tables’ were published in 1857 and they

improved upon Johann Burckhardt’s tables (Burck-

hardt’s were the basis of the Nautical Almanac at the

time).72 On 14 March 1858 the end of an annular solar

eclipse was observed at Harvard College Observatory

by G.P. Bond with the finder of the Great Refractor at

2¾-inch aperture, R.T. Paine with the ‘State Equa-

torial’, full aperture 3-inch, W.C. Bond with the

Bowditch comet seeker and an aperture of 3 ¾-inch,

and H.P. Tuttle with the ‘Fraunhofer’ telescope at 2½-

inch aperture.73 For the partial solar eclipse of 29 July

1859 Bond, Hall, and H.P. Tuttle observed.74

The solar eclipse of 18 July 1860 (which Warren

De La Rue photographed so successfully) was ob-

served as partial in Cambridge by Bond, Tuttle,

Safford, and Paine.75 The New York Times reported

just two days later: ‘The observations have as yet

been only in part reduced, but sufficiently so, to

indicate very clearly the superiority of the lunar tables

of Hansen over those of Burckhardt’.76

Comet seeking

Horace P. Tuttle took up comet seeking in 1857 with a

dedication that would quickly establish this twenty-

year-old as Harvard’s most indefatigable hunter. The

four-inch Merz equatorial had just been transformed

into the ‘improved Bowditch comet-seeker’: it was

now a broken-back altazimuth with a large prism that

bent the image into the centre of the altitude axis. The

eyepiece would now remain stationary as the observer

swept the refractor from horizon to horizon, and there

were no more blind spots near the zenith.

Comet 1857 II

Harvard memoranda of H.P. Tuttle have never been

published, though they offer insight into the early

history of the Observatory. In his personal logbook,

‘Comet Seeking’, H.P. Tuttle wrote:

The first Comet I ever discovered was ‘Brorsen’s

Periodical Comet’, in April 1857, some two weeks

after it was discovered by Dr. [Karl] Bruhns of

Berlin. When discovered by me it was more than

twice the diameter of Jupiter. Mr. G.P. Bond saw a

tail but I could not. This comet passed off to the

north east and disappeared in or near Ursa Major. 77

Theodor Brorsen (Kiel) discovered this comet in 1846.

It passed within one-half Astronomical Unit of the

Earth in March 1846, and was predicted to return in

1851, but was not recovered. On 18 March 1857 Karl

Fig. 16 Cover of one of H.P. Tuttle’s personal comet seeking logbooks. H.P. Tuttle’s personal memorandum book U.S. Naval Observatory, unpag.


86

Bruhns (Berlin) was first to recover it.78 Newspapers

reported that the comet might hit the Earth. Though its

density would be low, the comet was moving at a high

velocity. ‘Even the wind of a cannon ball has been

known to kill a man’.79 The New York Weekly Herald

cited the reassuring ephemeris of C.W. Tuttle, who

showed that at its closest the comet was ‘twenty

millions of miles distant, though invisible to the

naked-eye, and rapidly receding’.80 But in New York

state two deaths were attributed to ‘fears of the

comet’: a woman who took a woodland fire for the

comet and ‘went into convulsions and died’, and a

man ‘who made himself crazy over [the comet], and

then committed suicide’.81 C.W. Tuttle showed the

comet to news reporters on the nights of 14 and 15

May. In strong twilight and a full Moon it appeared as

‘a round, nebulous mass of light, slightly con-

centrated, of about two arc minutes in diameter’.82

Comet 1857 V

H.P. Tuttle recorded his second comet discovery on

the night of 23-24 August 1857. He had begun ob-

serving at midnight; at forty minutes past he spotted

an object ‘near the head of Camelopardalus’.83 Tuttle

wrote: ‘This comet was quite bright when first seen by

me, and in less than three weeks was visible to the

naked eye soon after sunset. The tail of this comet

made its appearance within 24 hours and was seen by

me with a 5-foot telescope to be 4º in length.’ Begin-

ning on 25 August 1857, and for over a fortnight, the

comet took first priority for observing time on the

Great Equatorial. Richard F. Bond observed positions,

and H.P. Tuttle recorded. On 2 September, Tuttle

noted: ‘The comet seems brighter than last night al-

though the full moon is shining brightly’.84 On 9

September, Richard F. Bond wrote: ‘Comet plainly

seen with naked eye though there is considerable haze.

A tail of 1 degree about points apparently towards the

Sun. In the Great Telescope the tail is seen for the first

time & points directly down [and] apparently is

narrower than the head’.85 On 10 September 1857

Tuttle wrote:

The tail of this comet suddenly made its app-

earance between the 7th and 8th of this month. It

was plainly seen on the evening of the 8th with the

five-foot Equatorial, and appeared to be between

2º and 3º in length. On the evening of the 10th it

had increased in length and brightness and reached

through 2/3ds of the field of [the] Comet Seeker

(between 3º & 4º) as will be seen on the figure . . .

The log entry for September 15 1857 was illustrated

with a depiction of the comet:

The comet presents a most beautiful appearance

this eve being very much brighter and in the [Great

Telescope] a well-defined and bright nucleus. The

tail is [about] the length of [diameter] of field of

[the] Comet Seeker (=4 ½ º) very straight, that is

of the same breadth the whole length.

H.P. Tuttle gave this description of his comet seeking

on 23 September 1857, and we can imagine how he

would spend as many as nine hours sweeping in one

night:

The sweeping this evening were made from the

east and west balcony through the following

[Constellations]: Libra Scorpio Ophiucus Hercules

Bootes Canes Venataci Ursa Major Ursa Minor

Andromedae Cassiopea Perseus Cameolepardalus

Lyra Auriga Taurus Geminni Orion. The only

object seen was in Ophiucus as it was just setting I

had no time to make a map of the surrounding

stars.86

Comet 1857 VI

The discovery of Tuttle’s third comet is recorded in

his logbook:

The third comet discovered by me, was on the 11

of November 1857 in the [Constellation] or near

the head of Draconis. It was small & faint when

first seen but increased in brilliancy for 3 or 4 days

and then faded away. It was not visible to the

Great Refractor more than 18 days.87

Fig. 17 Comet 1857 V, 10 September 1857, by H.P. Tuttle. Equatorial Book H.23, Harvard Observatory

Archives KG-11365-177, unpag.


88

had in a measure subsided, I commenced sweeping

in the north and went round to the west, when on

bringing my telescope toward the zenith I per-

ceived a faint object in Leo Minor. . . . On the next

evening May 3 it had moved . . . . which put its

cometary aspect beyond a doubt.96

The Great Equatorial was turned to Tuttle’s newest

comet on the evenings of 3, 4, 12 and 13 May. On the

twelfth G.P. Bond noted ‘Comet is still very faint, but

perhaps a little brighter than on the 4th [of May].97 On

6 June a comparison star was selected for astrometry

of the comet, but ‘students from the college’ pre-

empted astrometry. The following night another com-

parison star was selected, but despite a search the

comet could not be found.98 H.P. Tuttle described

Comet 1858 III as ‘the faintest Comet I ever saw. I

think it was somewhat brighter about the 10th [of

May] than at the time of its discovery. The last time I

saw it was with the Comet Seeker on the 14th of May,

and that with difficulty. The moon and cloudy wea-

ther prevented me from seeing it again’.

Tuttle’s discovery of Comet 1858 III was

significant, as the comet was observed only at one

other observatory, Detroit Observatory at Ann

Arbor.99

Comet 1858 VI (Donati’s Comet)

The saga of the most brilliant comet in the history of

the Harvard College Observatory, Comet 1858 VI,

began on the evening of 28 June, when H.P. Tuttle

‘accidently discovered Donati’s Comet, in Leo’.100

Giovanni Battista Donati at Florence had discovered it

by telescope on 2 June, but it had yet to be seen in

America. In another month, Donati’s comet would

become a naked-eye object, and develop the most

wonderful tail and coma structures. George P. Bond’s

study of Donati’s Comet became his magnum opus,

for which he was awarded the gold medal of the

Royal Astronomical Society.101 H.P. Tuttle

contributed many useful observations of the comet.

While in Dover, New Hampshire on September 28,

Tuttle discovered a new tail of the comet, seen in

Figure 20.102

The appearance of Donati’s comet raised public

interest in the Harvard College Observatory to new

heights, to the dismay of the Bonds:

During the 1st week of October the Comet became

the leading object of public interest. We had fine

skys [sic] & no Moon light. Experienced much

pressure of applications for a sight & had difficulty

in reserving time enough for the observations.103

Now Donati’s comet was shining its light on the fad-

ing reign of director William Cranch Bond, as George

P. Bond sadly noted in the equatorial log for 5

October: ‘Father came up to see it at about sunset. It

was his last view at any object through the Great

Refractor’.104

Comet 1858 VII

Sunday evening, 6 September 1858 skies were clear at

the Harvard College Observatory. As he brought the

Bowditch comet seeker out onto the balcony, H.P.

Tuttle was thinking about two periodic comets, En-

cke’s and Faye’s, now due to reappear. Encke’s was

the shortest period comet known: just forty months to

complete its orbit about the Sun. Encke’s recovery

should have been a good challenge for Tuttle, but on 7

August came word that it had been found – by

Encke’s assistant Förster. Tuttle lamented: ‘It appears

that Encke retained the Sweeping Ephemeris in order

that the Comet might be first discovered at his Obser-

vatory – as it was found before he sent the Ephemeris

to the [Astronomische Nachrichten]’.105Tuttle planned

to find the comet, and he copied Encke’s predicted

position into his personal comet log. Comet Faye’s

prior appearance was seven and a half years before.

Asaph Hall computed an ephemeris for Faye’s comet

and Tuttle pasted it into his personal log. That night

comet sweeping would bring two rewards:

Looked at some objects which I found last week in

the south west. Then put the C. S. on the N. Bal-

cony with the high power on, and commenced

sweeping towards the east. About 11 o’clock I had

swept as far as Cappella and in first or second zone

south of it I saw a small but rather bright object

about 4º or 5º to the westward—which proved to

be a Komet!!!!!!! In the G. R. it had a slight

tail!!!! This and Encke’s Comet was not, one and

the same body!!106

Fig. 20 Donati’s Comet, 6 October 1858, H.P. Tuttle. H.P. Tuttle’s personal memorandum book, U. S. Naval Observatory Library, unpag.


Tuttle had spotted a suspect object, and had continued

sweeping. In only about ten fields of view to the East,

he found a second cometary object. At 1 a.m. on 6

September Tuttle could see that the first object had

moved, confirming its cometary status. Tuttle alerted

Richard F. Bond and at 4 a.m. the two of them set the

Great Refractor on the first comet. Micrometer mea-

surements were made in declination, then in right

ascension, using chronometer 236 and the right ascen-

sion verniers of the Great Equatorial. The comet’s

appearance was described in the memorandum book:

‘Comet not very faint – with a very slight brush of a

tail on side away from sun. Has sufficient concentra-

tion of light for good obs. But no stellar nucleus’.107

As twilight was fast approaching there was not time to

measure the second comet of the night, which was in

fact Encke’s Comet. W.C. Bond surmised that the

first of the two comets was the anticipated return of

Faye’s periodic comet, but this proved not to be the

case, and the seventh comet of 1858 is another

‘Comet Tuttle’.

The following morning newspapers proclaimed

the ‘Discovery of Two Comets’. W.C. Bond reported

that ‘two faint telescopic comets were discovered at

this Observatory during last night, by Mr. H.P. Tuttle.

One a degree south of the star Capella, and another

twenty degrees to the east of it’.108 That night (6

September) Charles Wesley Tuttle joined his brother

Horace and Richard F. Bond at the Great Equatorial to

observe ‘H.P. Tuttle’s Third Comet 1858’. In the

Tuttles’ hometown of Dover, New Hampshire, the

Dover Enquirer made sport of the new comet:

The Boston Courier says it is the penalty of

greatness to be imitated. No sooner does Donati’s

comet appear in the Western heavens with its far

reaching train of light, than Tuttle’s comet, a mere

tadpole, whisks its petty tail into view in the

constellation of Pegasus, and seems to demand as

much consideration as the illustrious Donati. –

Tadpole, you can’t Come’t. Had Tuttle been some

foreign savant, with an unpronounceable name,

instead of a New Hampshire boy, his comet would

doubtless have had as long a tail, and caused as

much talk, as that which has been scared up by the

“illustrious Donati”. The attempt of the friends of

the latter to bluff Tuttle’s comet off the track, can’t

succeed. Donati, you don’t do it.109

Horace was now living with his father, step-

mother, and siblings in the home they built one block

west of the Harvard College Observatory. Charles had

moved to Newburyport where he was practicing law.

His law partner Richard S. Spofford commented on

Charles’ continued involvement in the pursuits of the

Observatory:

[Charles] always continued to feel a profound and

active interest – a predilection, indeed, constantly

kept alive, and in a measure gratified, by the suc-

cess attending the career of his eminent brother,

Horace Parnell Tuttle. One of my most pleasur-

able remembrances is that of the meetings of the

two brothers, and their mutual enthusiasms, when

some new astronomical discovery brought them

together. Almost totally uninformed on the subject

which at such times they discussed, and even of

the terms employed, I had my share of the

enthusiasm in my appreciation of theirs . . .110

Early in October 1858, prolonged illness interrupted

H.P. Tuttle’s observing. On the morning of 9 October

he noted that the sky was clear, but that he was sick.

His next entry in his comet journal was dated Monday

evening, 29 November 1858. He swept for comets,

but ‘not having swept for nearly two months, this

night’s work was of little use’.111 With G.P. Bond he

looked for his ‘third comet’, but it could not be found.

‘The last time I saw it was Sunday night with the

comet seeker’. On the first of December Tuttle was

again ill, and by the 21st of December he noted that he

had not swept for comets an hour since the first of the

month. ‘My health is much better now, and I shall use

my best efforts to discover The First Comet of 1859’.

H.P. Tuttle showed an amazing dedication to the task

of comet hunting. On 28 December, Tuttle wrote:

I could work only about 30 minutes, for the wind

which had been blowing quite strong all day from

the north west, suddenly changed to the north and

blew with such violence as to shake the balcony

(with me and the comet seeker both on it) like a

leaf. This caused me to strike my colors forthwith.

Fig. 21 The Tuttle residence (highlighted), 25 Tuttle Street, Cambridge, MA. Atlas of the City of Cambridge (G.M. Hopkins Co., 1873), unpag.

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