4 GOULD — REDUCTION OF D AGELET S OBSERVATIONS. 



mer of the Academy ; lie had experience as a navigator, and was naturally selected as astrono- 

 mer to the expedition. He accepted the position with great reluctance, as his naval experience 

 had not left agreeable recollections ; he desired to continue the observations for his projected 

 catalogue of stars ; and he was about to be married. Still, he listened to the solicitations of 

 the Minister and of the Academy, and on the 23d of June, 1785, eight weeks after the last 

 date of his published observations, he left Paris, never to return. 



The history of La Perouse" s expedition is well known. With the two ships, Astrolabe 

 and Boussole, he visited Madeira and Brazil, passed around Cape Horn to Chili, touched at 

 the Sandwich Islands, coasted along the west coast of America, and remained for a time at 

 Monterey, in California. Leaving this port in September, 1786, he sailed for Manila, and 

 thence in the following spring passed to the northeastern coast of Asia, exploring the shores 

 of Japan and Kamtchatka. He left Petropaulowsk in September, 1787, and after visiting the 

 Navigators' and Friendly Islands, reached Botany Bay in February, 1788. From this point 

 came the last tidings of the expedition. La Perouse next contemplated an exploration of the 

 Polynesian groups ; but all traces of the explorers vanished here. Unwearying searches 

 proved fruitless, and it was not until after the lapse of nearly forty years that their fate was 

 discovered. The two .ships were wrecked in a storm upon a coral reef on the southwesterly 

 coast of the island Malicollo, one of the New Hebrides islands; and all on board perished, 

 together with all their scientific observations and collections, except the few journals which 

 had been previously sent home from Kamtchatka, and which possessed high geographical 

 value. 



D'Agelet had been interdicted by his commander from sending home any of bis observa- 

 tions, and all were thus lost forever, excepting such geographical determinations as had been 

 transmitted by La Perouse himself. We know that he established an astronomical observatory 

 at every port at which the vessel stopped ; that he made observations at each upon the vari- 

 ation and dip of the needle, the tides, and the pendulum. The excellence of his longitude 

 determinations is frequently commented upon by La Perouse, inasmuch as his results, by lunar 

 distances and by chronometers, agreed within less than the probable errors of the lunar tables. 

 From Kamtchatka he wrote that since leaving Manila they had explored and surveyed with 

 great exactness more than six hundred marine leagues of unknown coast, fixing all the 

 geographical positions with precision ; and that he and his assistant, d'Arbaud, had become so 

 accustomed to observations of lunar distances that they used them for verifying their chro- 

 nometers without uncertainty. His last letter was dated in March, 1788. A littlo rocky 

 island in the Japan sea still bears his name, given it by La Perouse, and transmits, through our 

 maps and charts, the memory of this gifted and deserving scientist, wbose valuable observations 

 havo passed almost unheeded for more than eighty years. Those of Lefrancais db 

 Lalande and Burkiiardt, subsequently made for Lalande with the same instrument and 

 certainly not greater precision, have proved so valuable, that it seems more than strange that 

 d' Agelet's results in initiation of the work which they continued should have remained almost 

 unregarded till now. From Monterey he wrote in 1786 that lie found the savages both 

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