Nature had endowed Bailly with the most happy memory. He did not write his discourses till he had completed them in his head. His first copy was always a clean copy. Every morning Bailly started early from his humble residence at Chaillot; he went to the Bois de Boulogne, and there, walking for many hours at a time, his powerful mind elaborated, cooerdinated, and robed in all the pomps of language, those high conceptions destined to charm successive generations. Biographers inform us that Crebillon composed in a similar way. And this was, according to several critics, the cause of the incorrectness, of the asperity of style, which disfigure several pieces by that tragic poet. The works of Bailly, and especially the discourses that complete the _History of Astronomy_, invalidate this explanation. I could also appeal to the elegant and pure productions of that poet whom France has just lost and weeps for. No one indeed can be ignorant of his works; Casimir Delavigne, like Bailly, never committed his verses to paper until he had worked them up in his mind to that harmonious perfection which procured for them the unanimous suffrages of all people of taste. Gentlemen, pardon this reminiscence. The heart loves to connect such names as those of Bailly and of Delavigne; those rare and glorious symbols, in whom we find united talent, virtue, and an invariable patriotism. HISTORY OF ASTRONOMY.--LETTERS ON THE ATLANTIS OF PLATO AND ON THE ANCIENT HISTORY OF ASIA. In 1775, Bailly published a quarto volume, entitled _History of Ancient Astronomy, from its Origin up to the Establishment of the Alexandrian School_. An analogous work for the lapse of time, comprised between the Alexandrian School and 1730, appeared in 1779, in two volumes. An additional volume appeared three years later, entitled the _History of Modern Astronomy up to the Epoch of 1782_. The fifth part of this immense composition, the _History of Indian Astronomy_, was published in 1787. When Bailly undertook this general history of Astronomy, the science possessed nothing of the sort. Erudition had seized upon some special questions, some detailed points, but no commanding view had presided over these investigations. Weidler's book, published in 1741, was a mere simple nomenclature of the astronomers of every age, and of every country; the dates of their birth and death; the titles of their works. The utility of this precise enumeration of dates and titles did not alter the character of the book.