Anchor, Patent Model

Elisha Trask Barlow sought to improve how anchors grab the seabed. His design exploits the force of a vessel pulling on the anchor to, in the inventor's words, "induce an effort in the anchor to take hold." This is the model Barlow deposited at the Patent Office with his application in 1869.

Many nineteenth-century anchor designs featured pivoting flukes. Barlow's innovation was to link them to a sliding double shank. When strain is placed on the shackle at one end of the anchor, the uppermost part of the shackle is pulled forward, forcing the flukes to rotate down. As the anchor cable tries to drag the anchor forward, the downward pointing flukes are driven into the ground. "This arrangement of the parts of an anchor is most complete," Barlow said, "as the flukes are always governed by the strain on the cable, and [the anchor] can by no possibility become detached from its position when once it is set in the ground, unless a vertical strain should be brought to bear upon it, or the anchor should be turned over by the movements of the ship, in which case it will immediately take hold again."

Barlow, a machinist, lived in San Francisco, California.

Where this page came from

This page was imported from Smithsonian National Museum of American History. Released by the Smithsonian Institution under CC0 through Smithsonian Open Access.

Nobody has written it yet — it is the source material at a new address, which is why search engines are asked to skip it and why no one earns from it. It is up for grabs: take it on, and it is yours to rewrite and to earn from.