short years to write the immortal Declaration, then revolutionary doctrine, that nations and peoples have a right to freedom of development, he was now oblivious of the fact that Linnæus was engrossing the attention of the world of science by inaugurating his peaceful revolution in classification and nomenclature. He was much more concerned with the smiles and frowns of Miss Sukey Potter and her friend, Miss Belinda Burwell. As he entered young manhood, among the prominent figures of earlier days now passing from the stage were some familiar to us: Cadwallader Colden, the botanizing governor of the New York colony died in the year of the Declaration of Independence, Bernard de Jussieu and John Bartram one year later, Linnæus two years later, and his pupil, the Swedish botanical explorer, Peter Kalm, three years later.
Among those who were boys with Jefferson were Humphrey Marshall, one of that famous group of Philadelphia Quaker naturalists who left his mark on American botany in his little book entitled "Arbustum Americanum"; Adam Kuhn, the first professor of botany in the College of Philadelphia, and perhaps in the whole country; André Michaux, the elder of that pair of French travelers and naturalists who added so largely to the botanical knowledge of America, and lastly, Laurent de Jussieu, through whose work chiefly the so-called Natural System of Classification found form and currency.
In Jefferson's first administration (1801–1805), Dr. Benjamin S. Barton, of Philadelphia, published his "Elements of Botany," the first great American botanical text-book, and Dr. David Hosack established near New York his Elgin botanical garden, later attached to Columbia College.
In the years immediately following Jefferson's retirement from the presidency appeared Barton's "Flora Virginica" (in part), F. A. Michaux's "History of the Forest Trees of North America," Pursh's "Flora Americæ Septentrionalis," and Mühlenberg's "Catalogue," which a few years later was brought on to the basis of the Natural System by the versatile diplomat, Abbé Corrêa, the Portuguese Minister to the United States. This same period witnessed the remarkable advance in chemistry marked by the discovery of oxygen by Priestly, from whom Jefferson received many letters. The work of Ingenhauss, of Vienna, and that of DeSaussure and of Senebier at Geneva developed the basal facts concerning the gaseous interchanges taking place in respiration and photosynthesis in plants. Thomas A. Knight, the pioneer in physiology and plant breeding, and Sir Humphry Davy, the great chemist and physicist lived their most active days concurrently with Jefferson—also that "scourge of the human race," Napoleon. Jefferson's death took place in 1826, the year of the appearance of Darlington's "Florula Cestrica." It will bring Jefferson nearer to us to recall that in that year Asa Gray, whom the older of us here present this evening might
