Frames or blocks containing pulleys or sheaves are used in combination for lifting heavy weights.
The rope, which is guided upon sheaves between the rails, is taken twice round the head pulley.
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.
He recommends the practice of setting up corn in shocks, with two sheaves to cover eight, instead of ten sheaves as at present - probably owing to the straw being then shorter.
The tail rope, which is of lighter section than the main one, is coiled on the second drum, passes over similar guide sheaves placed near the roof or side of the gallery round a pulley at the bottom of the plane, and is fixed to the end of the train or set of tubs.
The Eskimo lifted his weighted boat with sheer-legs made of two paddles; he also had a tackle without sheaves, formed by reaving a greased thong through slits cut in the hide of a walrus.
It may eve nbe stacked without tying into sheaves, though this course involves greater expenditure of labour in carrying and afterwards in threshing.
After the process has proceeded a certain length, the crates are withdrawn, and the sheaves taken out and stooked.
From all such property, whether land or the sheaves and fruits of land, and also from the personal property of burghers in the towns; Knox now held that the state should authorize the kirk to claim the salaries of the ministers, and the salaries of teachers in the schools and universities, but above all, the relief of the poor - not only of the absolutely "indigent" but of "your poor brethren, the labourers and handworkers of the ground."
A pulley carried on a rotating shaft and connected to another pulley on a second shaft by an endless band consisting of a flat belt, rope, chain or similar connector serves for the transmission of power from the one shaft to the other and is known as a driving pulley; while combinations of pulleys or "sheaves," mounted in fixed or movable frames or "blocks," constitute mechanisms used to facilitate the raising of heavy weights.
In the arrangement shown there are three equal sheaves in each block, and each set turns on a pin secured in the framing.
She did not understand why he spoke with such admiration and delight of the farming of the thrifty and well- to-do peasant Matthew Ermishin, who with his family had carted corn all night; or of the fact that his (Nicholas') sheaves were already stacked before anyone else had his harvest in.
Subsequently straws are selected from the sheaves, and of these the pipes of the two upper joints are taken for plaiting.
The main rope, which draws out the loaded tubs, coils upon one drum, and passes near the floor over guide sheaves placed about 20 ft.
It becomes, therefore, necessary to balance in some way the varying displacement of the ram if economy is to be secured in the working: this is often done by the use of counter-weights attached to chains travelling over head sheaves, but this largely destroys the simplicity and safety of the direct-acting lift, and hence some form of hydraulic balancing is more satisfactory and more certain.
They drew the plough, trampled the corn sheaves round the circular threshing floor, and were sometimes employed to drag heavy weights.
5) is fixed, and the other B is movable, and a rope or chain, with one end secured to one of the blocks at C, passes round the sheaves in a continuous coil, leaving a free end D at which the effort is applied.
In order to obtain a greater ratio of R to E, without using a large number of sheaves, various arrangements are used, of which the' Weston differential pulley block is a typical example.
Twice in every year the sheriffs and other royal officials came up to the exchequer court, which originally sat at Winchester, with their bags of money and their sheaves of accounts.
From the time the sheaves of wheat are tumbled into the wagon until the flour reaches the hands of the cook, no hand touches the wheat that passes through the great Minneapolis mills.
The Tian-shan consists almost everywhere of " sheaves " of parallel ranges, having their strike predominantly east and west, with deflexions to the W.S.W., west of Khan-tengri and to the E.S.E., east of 92° E., thus describing as it were a wide flattened arc open to the south.
The interiors are cut up into numerous small rooms by transverse partitions, while numerous beamholes and dumb-sheaves indicate other divisions.