The harbor masters supervised the water traffic in people and goods in and out of Delft that was so important to its economic vitality.

Delft depended on successful water management for its existence. It depended on water transport for all of its imports and exports. Thus, the people who supervised the water system were crucial to the ongoing maintenance of the system. Every year, beginning in the 1480's, Delft's Council of Forty appointed one of three harbor masters (havenmeester) to a three year term.

The harbor masters had to work together, of course, because their areas of responsibility literally flowed into each other. The master of the inner harbor (havenmeester binnen) was responsible for the grachten within the city's walls. The master of the outer habor (havenmeester buiten) was responsible for the canals outside the city's walls, especially the harbor at the south end of town (right; click to enlarge). Delfshaven may have been eight miles away, but it was still considered part of Delft, so the city fathers provided for a harbor master there, too.

They also worked with the city official (fabriek) who we would now call the city engineer. He planned, mapped, and maintained the grachten within the city and the walls, gates, and towers around it. To do so, he supervised the carpenters, bricklayers, painters, and others who did the labor.

Between 1481 and 1724, Council of Forty made 116 appointments to the posts of inner and outer harbor masters and 112 to the post of Delfshaven harbormaster. None of Leeuwenhoek's relatives was ever inner harbor master. Only two were appointed as outer harbor master, and only one as Delfshaven harbor master.

  • JanĀ Dircks Uyttenbrouck, Cornelia's great great-grandfather, 1528
  • Maerten Jans Hogenhouck, great-grandmother Neeltje's brother, 1578
  • Gerrit Jans van der Eyck, great-great-uncle on both branches of his mother's side of the family, 1589