BLOCKS, on ship-board, is the usual name for what we call pullies 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.
The blocks now used in the navy are made in Portsmouth by means of circular saws and other machinery, which have been lately erected by a most ingenious mechanician. This machinery performs the several operations, from the rough timber to the perfect block, in the com pletest manner possible. The whole is
worked by means of a steam-engine ; the manual labour required is simply to sup ply the wood as it is wanted to the seve ral parts of the machinery, so that the commonest labourer almost may be made to act in this business with very little in struction.
Fish block is hung in a notch at the end of the davit ; it serves to hale up the Books of the anchor at the ship's bow.
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 capstan.