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Popular Science Monthly/Volume 4/April 1874/United States Naval Observatory

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584707Popular Science Monthly Volume 4 April 1874 — United States Naval Observatory1874Emma M. Converse

THE UNITED STATES NAVAL OBSERVATORY.

By EMMA M. CONVERSE.

THE importance of establishing a first meridian for the United States at the seat of government, in connection with a National Observatory for the purpose of systematic scientific observation, attracted the attention of Congress as early as 1810. In 181 3 the report of the committee, to whom the matter had been intrusted, was read before the House by one of its prominent members. But such were the disturbed condition of the country, and the absorbing interest in its military affairs during the war with Great Britain, that the subject was not again revived till 1815, when the original memorial with the several reports, hitherto presented, and the letter of the Secretary of State, read before the House in 1813, were referred to a select committee. This committee strongly advocated in its report the erection of a National Observatory, furnished with suitable instruments and apparatus for astronomical observation, and that the President should cause such observations to be made as would determine the longitude of the Capitol with the greatest practicable degree of exactness.

But no steps were taken at that time to carry out the resolution, and the subject was not again referred to till 1818. A third memorial was then presented, soliciting not the erection of an observatory, but simply that additional observations be made to test the accuracy of results already obtained, in order to insure a correct determination of our longitude from Greenwich. Nearly three years of tedious delay were required before the requisite resolution was passed which insured the modest commencement of what is destined to become one of the great scientific institutions of the country, and, we trust, of the civilized world.

In 1821 Mr. Lambert, the original memorialist, was appointed by the President "to make astronomical observations by lunar occupations of fixed stars, solar eclipses, or any approved method adapted to ascertain the longitude of the Capitol from Greenwich." In 1823, President Monroe submitted to Congress Mr. Lambert's final report, in which he stated that by the diligent use of such instruments for his work as the country afforded, by the employment of different methods, and by the assistance of competent persons in various sections of the United States to test the accuracy of his work, he had endeavored to fulfill his commission to the extent of his ability. He gave, as the mean result, the longitude of the Capitol 76° 55' 30" 54 west from Greenwich. Thus the first step in the establishment of an observatory was taken in determining the longitude of the Capitol; for, without such an institution furnished with suitable instruments and apparatus, no accurate measarements of the positions of the heavenly bodies could be made, and the computation of a nautical almanac or astronomical ephemeris would be impossible.

The next movement that was made toward the accomplishment of the object was in 1825, when President Adams, in his first message, urged upon Congress the establishment of a National University. Connected with this, he earnestly recommended the erection of an astronomical observatory, to watch the phenomena of the heavens, and to give periodical publications of observations. The matter was referred to a select committee, who presented an elaborate report in 1826, accompanied by a bill to establish an observatory in the District of Columbia. Although the location, cost of the edifice, and the expense of carrying it on, were freely discussed, no action was taken in the matter; and Mr. Adams's recommendation, though associated with the progress of the nation, and independent of party or personal interest, was allowed to lie unnoticed.

But, after years of neglect and indifference on the part of Congress, a few officers of the navy had the honor of taking the first direct action in the creation of the institution. In 1830 the Depot of Charts and Instruments for the Navy was established in Washington. This was accomplished under the orders of the Navy Commissioners, and with the sanction of the Secretary of the Navy. Lieutenant Goldsborough, through whose influence principally the bureau was created, was intrusted with the charge of it. He collected from New York and other places the chronometers, sextants, theodolites, and other instruments and charts of the navy, and located them in a building opposite the residence of the Attorney-General, Hon. William Wirt. A transit instrument was afterward added, and the naval Depot of Charts and Instruments was in working order. One duty of the officers was the careful rating of all chronometers belonging to the navy, which was at first effected by sextant and circle observations; but afterward with a thirty-inch transit instrument. This transit was mounted within a small circular building upon a brick pier having a base twenty feet below the surface, and is noteworthy as the first astronomical instrument erected for the navy at Washington.

In 1833 Lieutenant Wilkes succeeded to the charge of the depot, and obtained permission to remove the office to Capitol Hill, where it remained until 1842. He erected here at his own expense an observatory sixteen feet square, and mounted a five-foot transit. But no regular observations were made till 1838, on the departure of the exploring expedition, the principal use made of the transit being the determination of time. In 1837 Lieutenant Gilliss was left in charge of the depot, and, during the absence of the exploring expedition, and in connection with it, made invaluable observations on moon culminations, occultations, and eclipses. There was not a visible culmination of the moon, occurring when the sun was an hour above the horizon, from 1838 to 1842, nor an occultation after the 15th of June, 1839, with one exception, which he did not personally observe. He also completed an important series of magnetic and meteorological observations.

As the work took on larger proportions under such devoted leadership, and valuable and expensive instruments were added, the unsuitableness of the building, the defects of the transit-instrument, and the want of space to erect a permanent circle, became more evident. Earnest solicitations were made for an appropriation for a permanent establishment, and the subject was brought before Congress by the Secretary of the Navy in 1841. Tedious and disheartening delay occurred before Congress was roused to an appreciation of the importance of the enterprise. But, after persistent effort on the part of its supporters, at the last hour of the session of 1841-'42 a bill passed both Houses without discussion, authorizing the Navy authorities to contract for the building of a suitable institution, and that it should be located on any unappropriated land in the District of Columbia which the President deemed suitable. Thus was the future observatory officially recognized.

All obstacles to further progress being happily overcome, plans for erecting a Naval Observatory under the best available conditions were speedily made matter for diligent study. Visits were made to the Northern cities to obtain assistance, distinguished astronomers were consulted, and an accomplished architect secured to draught plans, the whole care being intrusted to Lieutenant Gilliss. The locality chosen for the observatory possesses an historic interest. The site assigned to it was known as "Reservation No. 4," on the original plan of the city. It lies on the north bank of the Potomac, in the southwestern part of the city. When General Braddock marched against Fort Duquesne in the colonial wars, his troops landed and encamped on this hill. Washington's letters show that he crossed at this point from Alexandria to join Braddock at Frederick. A large rock within the grounds of the observatory is pointed out as the spot on which these landings were made. It was here that the first President proposed to locate a national university, and at a later date it was suggested by President John Quincy Adams for the site of an observatory. The base of the observatory is the second highest eminence within the city limits, and is on a level with the floor of the Congressional Library.

In 1843 Lieutenant Gilliss reported to the Navy Department the adoption of a plan for an observatory, and also the progress of the erection of a building in accordance with the plan. In 1844 the new building was ready for occupancy, and the instruments adjusted for the commencement of active work. The central building is about fifty feet square, raised on a firm foundation, and built of brick in the most thorough manner. It is two stories and a basement high, with a parapet and balustrade of wood around the top, and is surmounted by a revolving dome resting on a circular wall. The roof is nearly flat, and so arranged as to form a level promenade for gazing observations. On the east and west sides of the building are wings, and also on the south. In 1870, an observing-room for the transit-circle was added, forming an extension of the west wing. A tower and dome, to accommodate the superb new equatorial telescope recently completed, was finished in October. The equipment of the observatory in astronomical, magnetic, and meteorological instruments is now in a fair way to become worthy of the institution and the country it represents, and the library is increasing rapidly in the number of volumes and their scientific value.

Among the influences that helped to bring about this auspicious result were, in the first place, the unswerving interest and indefatigable zeal of Mr. John Quincy Adams. Although his suggestions concerning the establishment of a national observatory were treated with neglect during the term of his presidency, he did not lessen his efforts in the cause dear to his heart. In 1838 he presented its claims before President Van Buren, and in 1842 in his place in the House of Representatives. The report of the committee, presented at this session by Mr. Adams, should be read by every student of astronomy, for the fervor of its eloquence and the nobility of the truths it enunciates. Lieutenant Gilliss was equally unwearied in the cause. It was by his diligent and successful observations that he secured the essential confidence and coöperation of the Navy Department, and of the naval committees. He was the first person, in the United States, who gave his whole time to practical astronomical work. He first published a volume of observations, prepared a catalogue of the stars, and planned and carried into effect the construction of a working observatory, in contrast with one intended simply to teach. For this arduous work he was specially gifted, possessing a wondrous acuteness of the perceptive powers of eye and ear. Prof. Peirce, after examining his observations from 1838 to 1842, gives him the second place in the long list of observers, living and dead, whose results were critically and searchingly tested by the so-called personal scale. Profs. Bartlett, Kendall, and Walker, contributed largely by their labors to the establishment of the institution. Their series of astronomical observations, their publications, and the able report on European observatories, by Prof. Bartlett, in 1840, had a powerful influence in rousing public interest in the subject, and, combining with other influences, produced the desired result.

In 1844 Commander Maury was appointed superintendent of the new observatory, assisted by the same officers who had been attached to the Depot of Charts. Under the instruction of the Secretary of the Navy, the most extensive astronomical work was proposed in cataloguing the stars. The task set before the infant observatory, said a critic in the North American Review, was "nothing less than assigning color, position, and magnitude, to every star in the heavens, which could be seen with the instruments." With the resources at the command of the officers at that time, it would have required a century to complete it.. The work was, however, commenced of making a catalogue of the stars down to the ninth and tenth magnitude. In 1846 the first volume of observations was issued from the press. In 1847 the observatory was first brought into prominence by the identification of the newly-discovered planet Neptune, with a star of Lalande's catalogue of 1795. Astronomers thus obtained an observation of Neptune made fifty years before, which afforded the means of an accurate determination of its orbit; and the superintendent of the "American Nautical Almanac" was enabled to publish an ephemeris of the new planet two years in advance of all other parts of his almanac. In 1848 the institution first bore the name of "United States Naval Observatory" instead of "National," an honor justly due to the Navy Department which controlled it, and to the navy officers who had charge of its interests. But the preparation and publication of Wind and Current Charts absorbed the attention of the superintendent. With the exception of the equatorial and mural circle-observations, zone-observations, and several years' unpublished work of other observers, regular astronomical work did not receive the prominent attention demanded for the best interests of the observatory. In 1861 Lieutenant Maury left his position to join the cause of the Confederate States of the South.

Captain Gilliss succeeded to the office in 1861. His heart and hand were in the work. He published the volume of observations for

1861 promptly in 1862. He gave detailed statements of the volumes of observations he found unprepared for the press, took measures for their publication, for the regular and prompt issue of annual volumes from the observatory, and arranged that meteorological observations should form a part of each volume. The volume of observations for

1862 contained a discussion concerning the longitude of Washington; a paper on Comet II., 1862, with drawings of the comet during the period of greatest brilliancy; and a plate illustrating the appearance of Mars, near the opposition in that year. The special work for 1863 was an investigation of the solar parallax from observations on the planet Mars. Nearly 11,000 observations were made with four instruments during this year. A transit-circle was also contracted for to improve the defective equipment of the observatory. But, while the field was widening before him, and when neither of his three favorite aims had come to a successful issue, Captain Gilliss was suddenly removed by death, in 1865, from the scene of his labors.

Rear-Admiral Davis was placed in charge of the observatory in 1865. During the same year the great transit-circle was completed, and placed in position in the then west wing of the observatory. This constituted an era in its history, and raised it to a more fitting rank among institutions of its class. The volumes of observations for 1863 and 1864 were published in 1865 and 1866. The meteorological observations from 1842 to 1867 were fully discussed, a report was made on interoceanic canals and railroads, and the regular routine work was diligently kept up. In 1867 Rear-Admiral Davis was ordered to take command of the South-Atlantic Squadron.

In 1867 Rear-Admiral Sands became the fourth superintendent, and is the present incumbent of the office. Since that time the work has so greatly increased in all directions, and the progress of science demands such an amount of labor, that the limits of this article will permit only a brief mention of a few of the most important portions of the work accomplished. One of the recent publications of the observatory is a "Manual of its Founding and Progress," prepared by Prof. Nourse. We refer readers, who desire more extended information, to this able and exhaustive paper, to which we are indebted for our facts and suggestive information. Under the present superintendent, and his efficient and cooperative assistants, the observatory has gone steadily forward, enlarging its boundaries, and widening its field of vision. The current years have been rich in results in the regular work of the institution, as the published volumes of observations bear testimony. A new observing room for the transit-circle was erected in the west wing, and the mounting of the circle was completed in 1870. The library was removed to the room previously occupied by it, and now numbers more than 5,000 bound volumes. The total solar eclipses of August 7, 1869, in America, and December 22, 1870, in Europe, were closely observed by parties from the observatory, and full reports of their observations were published.

But the greatest achievement toward raising the observatory to a higher rank among its peers was the successful completion and mounting, in the new tower and dome prepared for it, of the Great Equatorial, in the month of October of the past year. This auspicious event is largely owing to the persevering effort of the superintendent. After repeated representations concerning the necessity of the instrument, Congress made an appropriation of $50,000 for the purpose. The contract was made in August, 1870, with Messrs. Alvan Clark & Sons, of Cambridgeport, Mass. They agreed to construct a refracting telescope, of good definition, and of 26 inches clear aperture, mounted equatorially on the German plan, and supplied with all the appliances that modern science has developed. They required four years to complete it. But the opticians were ahead of their contract, and the observatory is now rejoicing in the absolute possession of the talismanic instrument which has been the object of its ambition.

The future work of the institution will demand all its resources. It is already in the full tide of preparation for the observation of the coming transit of Venus in 1874, for which it has received an appropriation of $150,000. It is looking forward to still more satisfactory results from the transit of 1882, which will be specially favorable for observation on American ground, while an opposition of Mars, in 1877, will test the power of its new possession.

With this grand telescope and its equipment, with a personnel made up of officers who honor their profession, with Congress ready to grant all needful aid, there is every reason to anticipate a future for the United States Naval Observatory, honorable to itself, and honorable to the country it represents.