Along the main road adjacent to the museums stands an excellent display of old anchors. This display shows clearly how the old fashioned Admiralty Pattern anchor evolved.
The anchors were made from cast or wrought iron. The cross-member, or stock, is at right-angles to the flukes: as ther anchor lands on the bottom, the stock causes it to fall sideways so that one of the flukes can dig into the sea-bottom (also known as "the ground"). Older ships' anchors had a built-up wooden stock. Attached to the anchor is a long length of heavy chain, known as "the cable". Once the anchor has set itself, the ship pays out a length of cable about equal to six times the water depth, so that the heavy links lie on the bottom, the pull on the anchor being almost horizontal, so that the fluke won't break out. A ship is said to be "dragging anchor" if, in a storm or because of soft (or bad) ground, it loses its grip.
On setting sail again, the cable is winched in so that the pull approaches the vertical, and the fluke breaks out. This is described as "to weigh anchor". Anchors on sailing ships were stowed and lashed just under the bowsprit, or brought inboard and secured on the forward deck. Some Admiralty Pattern anchors had a folding stock (see above) whereby the stock went through an eye forged in the shaft, and could be folded alongside the shaft when not in use.
Among the Fremantle collection is an unusual example of a large "plough anchor"; probably used for permanent moorings, buoys etc. The next picture shows how an Admiralty anchor lies in position on the sea-bed:
An old wooden-stocked anchor.
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