Finding all his endeavours to sell his collection fruitless, he determined to expose it to public auction; but before the period arrived, his disease was much aggravated by the various agitations to which his mind was now habitually subject. The fever proved again regular and continuous, the countenance was emaciated, the eyes were sunk, the feet, the legs, and at length the whole body, dropsical. His friends dared not speak to him respecting his former studies, for he detested all allusion to them, and wished to withdraw his mind entirely from earthly concerns. At length, on the 25th January 1670, when he perceived his end approaching, he wrote his will, leaving to Thevenot all his original manuscripts on the history of bees, butterflies, and anatomy, with 52 plates; all of which were at that time in the house of Herman Wigendorp in Leyden, to whom they had been delivered to be translated into Latin. He bequeathed his property to Margaret Volckers, wife of Daniel de Hoest, appointing her and Christopher Wyland his executors. The remainder of his time he spent in devotion, and died on the 17th February. It was some years before Thevenot obtained possession of the manuscripts, and after his death they passed into various hands, but were bought in 1727 by the illustrious Boerhaave, who arranged and published them in two folio volumes, prefixing a life of the author, from which we have drawn the materials of this notice. The learned editor gives an interesting account of the instruments and expedients employed by Swammerdam in dissecting insects and other minute animals. When the anatomical preparations, insects, and apparatus, were offered for sale, no purchaser could be found, and the collection was subsequently dispersed. The manuscripts and drawings of the Biblia Naturae were deposited by Boerhaave in the library of the University of Leyden. The works of Swammerdam contain more original and accurate observations than those of any naturalist who preceded him, excepting Aristotle. He refuted numerous errors committed by his predecessors, and carried his observations to a degree of minuteness and accuracy truly astonishing; but it is not a little surprising that he succeeded less in describing the structure of large objects than in delineating the organs of the most minute.