Agricola, Georgius, De re metallica, 1912/1950
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1to draw water alone, I will explain how heavy bodies, such as axles, iron
chains, pipes, and heavy timbers, should be lowered into deep vertical shafts.
A windlass is erected whose barrel has on each end four straight levers; it
is fixed into upright beams and around it is wound a rope, one end of which
is fastened to the barrel and the other to those heavy bodies which are slowly
lowered down by workmen; and if these halt at any part of the shaft they
are drawn up a little way.
When these bodies are very heavy, then behind
this windlass another is erected just like it, that their combined strength
may be equal to the load, and that it may be lowered slowly.
Sometimes for
the same reason, a pulley is fastened with cords to the roof-beam, and the rope
descends and ascends over it.
95[Figure 95]
A—WINDLASS. B—STRAIGHT LEVERS. C—UPRIGHT BEAMS. D—ROPE. E—PULLEY.
F—TIMBERS TO BE LOWERED.
Water is either hoisted or pumped out of shafts. It is hoisted up after
being poured into buckets or water-bags; the water-bags are generally
brought up by a machine whose water-wheels have double paddles, while the
buckets are brought up by the five machines already described, although in
certain localities the fourth machine also hauls up water-bags of moderate
size.
Water is drawn up also by chains of dippers, or by suction pumps, or

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