(Reproduction of an optical device that Zacharias Snijder ...)
Reproduction of an optical device that Zacharias Snijder in 1841 claimed was an early telescope built by Jansen.
As besieged Antwerp was about to fall to the Spaniards, Zacharias Jansen’s parents fled to Middelburg. From there they often traveled to nearby fairs, where the husband plied his trade as an optician. Thus it happened that Jansen was born in The Hague in 1588, four years before his father died. His mother taught him how to manage his father’s shop in Middelburg. He also had a sister, Sara.
Through his neighbor Willem Boreel, the mintmaster’s son, Jansen learned how to counterfeit Spanish copper quarters. Although the nominal penalty was death and confiscation of property, Jansen was merely fined on April 22, 1613, for performing this patriotic act harmful to the former oppressors of the Dutch people. He moved to nearby Arnemuiden and escalated his counterfeiting to gold and silver coins. Condemned to death in 1618, he evaded the penalty by returning to Middelburg. Sued for nonpayment of the interest on his mortgage, he leased a house in Amsterdam. His failure to meet the installment due on May 1, 1628, was followed by bankruptcy and auction of his property.
Although twice convicted for counterfeiting, Jansen never pretended that he invented the telescope. Long after his death that false claim was made by his son on January 30, 1655, when the Middelburg authorities were taking testimony about the disputed invention to comply with the request of Willem Boreel, then Dutch ambassador to France. His request had been prompted by Pierre Borel, who was writing a book about the true inventor of the telescope.
In order to assert his father’s priority over all claimants, Johannes Sachariassen lyingly testified in 1655 that Jansen invented the telescope in 1590 because Descartes’s friend Isaac Beeckman had visited Sachariassen’s shop in Middelburg to improve his lens-polishing technique. In 1634, before April 30, Sachariassen privately told Beeckman that Jansen had made the first telescope in Holland in 1604 after an Italian model marked 1590. This had presumably been brought to Middelburg by one of the many immigrant Italian craftsmen.
Although the person who was responsible for the invention of the first optical telescope is not known, Zacharias Janssen's name is still associated with it. He is sometimes also credited for inventing the first truly compound microscope; however, the origin of the microscope, just like the origin of the telescope, is a matter of debate.
On November 6, 1610, Jansen's mother approved his marriage to Catharina de Haene. His son, Johannes Sachariassen, was baptized on September 25, 1611. His first wife died in 1624, and in the following year he married Anna Couget from Antwerp, who was the widow of a Willem Jansen.
