The portrait (Fig. 18) which forms a frontispiece to his _Arcana Naturæ_ represents him at the age of sixty-three, and shows the pleasing countenance of a firm man in vigorous health. Richardson says: "In the face peering through the big wig there is the quiet force of Cromwell and the delicate disdain of Spinoza." "It is a mixed racial type, Semitic and Teutonic, a Jewish-Saxon; obstinate and yet imaginative; its very obstinacy a virtue, saving it from flying too far wild by its imagination." Recent Additions to His Biography.--There was a singular scarcity of facts in reference to Leeuwenhoek's life until 1885, when Dr. Richardson published in _The Asclepiad_[1] the results of researches made by Mr. A. Wynter Blyth in Leeuwenhoek's native town of Delft. I am indebted to that article for much that follows. His _Arcana Naturæ_ and other scientific letters contained a complete record of his scientific activity, but "about his parentage, his education, and his manner of making a living there was nothing but conjecture to go upon." The few scraps of personal history were contained in the Encyclopædia articles by Carpenter and others, and these were wrong in sustaining the hypothesis that Leeuwenhoek was an optician or manufacturer of lenses for the market. Although he ground lenses for his own use, there was no need on his part of increasing his financial resources by their sale. He held under the court a minor office designated 'Chamberlain of the Sheriff.' The duties of the office were those of a beadle, and were set forth in his commission, a document still extant. The requirements were light, as was also the salary, which amounted to about £26 a year. He held this post for thirty-nine years, and the stipend was thereafter continued to him to the end of his life. Van Leeuwenhoek was derived from a good Delft family. His grandfather and his great-grandfather were Delft brewers, and his grandmother a brewer's daughter. The family were doubtless wealthy. His schooling seems to have been brought to a close at the age of sixteen, when he was "removed to a clothing business in Amsterdam, where he filled the office of bookkeeper and cashier." After a few years he returned to Delft, and at the age of twenty-two he married, and gave himself up largely to studies in natural history. Six years after his marriage he obtained the appointment mentioned above. He was twice married, but left only one child, a daughter by his first wife. In the old church at Delft is a monument erected by this daughter to the memory of her father. [Illustration: Fig. 18.--Leeuwenhoek, 1632-1723.] He led an easy, prosperous, but withal a busy life. The microscope had recently been invented, and for observation with that new instrument Leeuwenhoek showed an avidity amounting to a passion.