BLOCKS, on ship-board, is the usual name of what we call pulleys at land. They are thick pieces of wood, some with three, four, or five shivers in them, through which all the running ropes run. Blocks, whether single or double, are distinguished and called by the names of the ropes they carry, and the uses they serve for.
Double blocks are used when there is occasion for much strength, because they will purchase with more ease than single blocks, though much slower.
Block and block is a phrase signifying that two blocks meet, in haling any tackle, or halliard, having such blocks belonging to them.
Fish-block is hung in at a notch at the end of the davit. It serves to hale up the flocks of the anchor at the ship's prow.
Snatch-block is a great block with a shiver in it, and a notch cut through one of its cheeks, for the more ready receiving of any rope; as by this notch the middle-part of a rope may be reeved into the block, without passing it endwise. It is commonly fastened with a strap about the main-mast, close to the upper deck, and is chiefly used for the fall of the winding tackle, which is reeved into this block, and then brought to the captain.