leaf detailJuan de Lagar, Caulkerleaf right detail

Juan de Lagar was the son of Miguel and a native of Puerto de Santa María, a town near Cádiz, Spain. In the list of sailors on the Nuestra Señora de Atocha, he is described as a well-built man, thirty-three years old, with a blond beard and a wound scar on his left cheek. His task as caulker was to watch for water seeping into the ship and fix any problems. He made sure the seams between the planks of the hull and decks were sealed and watertight. He also maintained the bilge pumps, ensuring that any water that leaked into the hull was promptly removed.

The caulker’s primary means of keeping the ship watertight was to pack oakum, a mixture of hemp fibers and tar, into the seams between the planks of the hull and decks. A variety of hammers and chisels were used to drive the oakum into place. Pitch was smeared over the oakum and lead strips were tacked down the length of the seams to provide additional protection.

Oakum had to be replaced as it aged, and the caulker had special hooked tools to remove the old caulk and clear the seams for new. Sailors would help the caulker in their down time by picking apart old ropes to get the fiber and make oakum.