A case-containing several sheaves is called a block.
Frames or blocks containing pulleys or sheaves are used in combination for lifting heavy weights.
C, D, Sheaves carrying the endless chain of moulds.
At harvest the corn was cut high on the stalk with short sickles and put up in sheaves, after which it was carried to the threshing-floor and there trodden out by the hoofs of oxen.
In practice the full advantage of this or any other similar combination is not realized, because of the friction of the sheaves against the pin or shaft, and more important still is the stiffness of the rope, which requires work to be done upon it to bend it round the sheave and straighten it again.