SWAMMERDAM, JAN, a distinguished naturalist, was b. at Amsterdam, Feb. 12, 1637. Swammerdam, almost from his boyhood, showed the greatest eagerness in the study of natural history. Having entered upon the study of medicine, he particularly occupied himself with anatomy, and continued unremittingly to collect insects, to inves tigate their metamorphoses and habits, and, by the aid of the microscope, to examine their anatomic structure. He took his degree of doctor of physic at Leyden in 1667, and entered upon the practice of his profession, which his bad health, however, soon compelled him to relinquish. He continued to be chiefly engrossed with anatomy and i entomology. His treatise on bees appeared in 1673; a treatise on ephemera in 1673. It is impossible, however, for us to enumerate his many publications, all of which were first • published in Dutch, and afterward translated into Latin, and many of them into English, French, and German. Swammerdam's discoveries were very numerous, both inhuman • and comparative anatomy. His skill in using the microscope was very great, and his
manipulation of the most minute subjects extremely dexterous. He succeeded in giving distinctness to the forms of very minute viscera, by inflating them with air; a method of his own invention. It is melancholy to add, that Swammerdam, who had always displayed strong religious feelings, and expressed them in his writings, was at last car ried away by the fanatical extravagances of Antoinette Bourignon (q.v.), began to think all his former pursuits sinful, and relinquished them for a visionary religious life of mere meditation and devotion. His health rapidly declined, and he died at Amsterdam, Feb. 17, 1630. No man of his time contributed more than Swammerdam to the prog ress of natural history and physiology. He was the inventor of the method of making anatomical preparations by injecting the blood-vessels with wax, and also of the method of making dry preparations of the hollow organs, now generally employed.