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.