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.”
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.