BESSEL, Friedrich Wilhelm, a distinguished Prussian astronomer, was born at Minden on the 22d July 1784. At an early age he was placed in the countinghouse of a merchant at Bremen. His strong desire to obtain a situation as supercargo on a foreign voyage led him to the study first of navigation and then of mathematics. He devoted himself with the utmost ardour to mathematical and astronomical calculations, and in 1804 undertook the reduction of the observations made on the comet of 1607. His results were communicated to Olbers, who warmly praised the young astronomer, and in 1806 recommended him for the post of assistant to Schröter in the observatory at Lilienthal. In 1810, after his reputation had been much extended by various memoirs, treating particularly of cometary orbits, he was appointed director of the new observatory then being founded by the king of Prussia at Königsberg. He was at the same time made professor of astronomy and mathematics in the university of that town. Bessel, from his keen practical intelligence, thorough acquaintance with all instrumental appliances, and complete mastery of the methods of calculation, was ad mir ably fitted for the post of observer. The establishment at Königsberg was one of the best of its kind, and its observations, published continuously from 1813, are of great value. In 1818 Bessel completed a task on which he had been engaged for several years—the reduction of Bradley’s priceless but neglected Greenwich observations. The results were published in the volume entitled Fundamenta Astronomies, the importance of which for astronomical science cannot be overrated. By its publication the author at once took his place among the first astronomers of Europe; he was received with honour by the various foreign scientific ...