It’s not often that a layman untrained in science makes a fundamental discovery, starts a new branch of science, and alters the course of human history.  Nor is it often that a layman shows exemplary scientific technique that becomes a model for scientists to come.  Antony van Leeuwenhoek was such a person.  Extremely inventive, careful, and precise, unfettered by false notions of the day, Leeuwenhoek was driven by an insatiable curiosity that captivated him at age 40 and kept him going to his dying day at age 91.  It started when he read a copy of Robert Hooke’s new illustrated book Micrographia, which contained drawings of insects, cork, textiles and other things revealed under a microscope at magnifications about 20-30x.  Leeuwenhoek took to grinding his own lenses and making his own microscopes.  Perfecting a technique that raised the power to over 200x, he opened up a whole new world never before seen by man: the world of microorganisms.

Born in Delft, Holland, Antony did not have any inclinations or opportunities to become a scientist.  He would also know hardship and grief.  His father, a basket maker, died when he was five or six.  His mother was the daughter of a beer brewer.  She remarried a painter and bailiff, but he died when Antony was 16.  He was educated by an uncle, and never went to a university, never learned Latin (the scientific language of the day) or any other language other than his native Dutch.  By age 16, he was apprenticed to a textile merchant, and he became a drapery shopkeeper before he was 22.  He married Barbara de Mey, the daughter of a silk merchant about that time.  The Leeuwenhoeks had five children, four of whom died young.

Antony became a chamberlain in 1660, later a surveyor and an inspector of the measures for wine.  Through his appointments and possibly some inheritance, he attained a comfortable income with time to pursue what would later become his famous hobby.  His wife died in 1666 when he was 34; five years later, he married Cornelia Swalmius, the daughter of another cloth merchant who was also a Calvinist minister.  Her influence may somehow have stimulated Antony’s investigations into science, since these began within two years after their marriage.  This second marriage lasted 23 years till her death in 1694; Antony was cared for by his last daughter till his death in 1723, thus carrying on his scientific work for an additional 29 years after becoming a widower a second time.

Leeuwenhoek did not invent the microscope (compound magnifying lenses were known 40 years before he was born), but he took it to new levels of power.  He was probably acquainted with magnifying lenses used to investigate the textiles in his trade.  His only trip to London (between marriages, in 1668) introduced him to the unseen natural world under the magnifying lens shown in Robert Hooke’s popular new book, Micrographia.  We can only surmise what sparked his interest in microscopy that was in full bloom five years later; this book?  His second wife or her intellectual friends?  His own curiosity about nature?  Somehow, he began grinding his own magnifying glasses, and perfecting a way to mount them and hold specimens in position for viewing.  Crude by today’s standards, they were nevertheless far superior to those used by Hooke, Swammerdam, Malphighi and others, and were unsurpassed until the 19th century….

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