Jacob Spoors
The inscription on the cartouche below (my translation). This cartouche was used in 1675 by elderly Delft surveyor Jacob Spoors to decorate his map of Berkel.
This area, to the east of Delft, extended into the corner (lower right on the map) where the Delfland water management district bordered the neighboring Rijnland (Leiden) and Schieland (Rotterdam) water management districts.
This is the same Berkelse Meer to which Leeuwenhoek referred in his letter of September 7, 1674. In water from the lake, he first observed microbes (diertgens, little animals). What was he doing there? He was already a certified surveyor and he mentioned in a letter of 1713 that he and Spoors measured the height of the Nieuwe Kerk tower. Perhaps Leeuwenhoek assisted the elderly Spoors with both surveying tasks, Berckel in 1674 for this map a year later and Delft in 1676, the summer before Spoors died, for the Kaart Figuratief.
Spoors' life and work
A native of Delft, Jacob Spoors was trained as a surgeon, which was listed as his profession when he married Trijntgen Aelbrechts in 1614. They lived in Oud-Beijerland, near Dordrecht, where he was sworn in as a notary on January 11, 1623. A year earlier, he was admitted as a surveyor after his oral examination with Willebrord Snel of Leiden University. Spoors was interested in optics, and while still in Dordrecht assisted Isaac Beekman with some of his experiments on the nature of light.
He married for a second time back in Delft and at some point moved back and lived there for the rest of his life. By 1637, Spoors' notary records were being kept in Delft and continued there until January 1677, when he died. He is buried in the Oude Kerk.
Jacob lived on the both sides of the Oude Delft just north of the Binnenwatersloot. He lived in D0432 on the east side and after about 1650 in D0445 on the west side. When his son-in-law died in 1666, Spoors bought his D0447 next door.
Spoors and Leeuwenhoek belonged to the St. Nicolaas Gilde together for two decades, from the mid-1650's until Spoors' death.
On March 3, 1638, he and his second wife Elizabeth (Lijsbeth) baptized a son, Johan, who was clerking for his father by 1655. Elizabeth must have died because in 1667, Jacob married Trijntge Jans, widow of Jacob Cornelis Zuijtdijck.
In 1659, Jacob's son Johan married Leeuwenhoek's cousin Aletta Elzevier in 1659. Her mother, Cornelia Jacobs van den Berch, was Leeuwenhoek's aunt.
In 1638, Spoors published his only book, Oratie van de nieuwe wonderen des wereldts, de nuttigheyd, de waerdidigheyd, der wis- ende meetkunsten (Oration on the new wonders of the world, the utility, the dignity of mathematics and geometry). On the first page (right), he introduces himself as notary public, sworn-in surveyor, and attorney (procureur) for the Delft magistrate's court. It shows his familiarity with the recent history of optics, especially telescopes and the accomplishments of Europe's leading astronomers. He speaks of using a "seeing tool" (gesicht-gereetschap).
As a surveyor, Spoors participated in several large-scale mapping projects. The most notable was the Kaart Figuratief, for which he did the work in the year or two before his death in 1677 and its publication in 1678. Spoors' team of surveyors measured every parcel of land in the city with a chain (ketting, right). Spoors drew the traditional street map. Then Jan Verkolje, who painted Leeuwenhoek's portrait in 1686, drew every building in Delft, facade by facade.
The article "Most Rare Workemen" has the most complete account of Spoors' life and activities.