BOOK V. 



121 



it is on the sides they break it with hammers. Thus broken off, the rock 

 tumbles down ; or if it still remains, they break it off with picks. Rock 

 and earth on the one hand, and metal and ore on the other, are filled into 

 buckets separately and drawn up to the open air or to the nearest tunnel. 

 If the shaft is not deep, the buckets are drawn up by a machine turned by 

 men ; if it is deep, they are drawn by machines turned by horses. 



It often happens that a rush of water or sometimes stagnant air hinders 

 the mining ; for this reason miners pay the greatest attention to these 

 matters, just as much as to digging, or they should do so. The water of the 

 veins and stringers and especially of vacant workings, must be drained out 

 through the shafts and tunnels. Air, indeed, becomes stagnant both in 

 tunnels and in shafts ; in a deep shaft, if it be by itself, this occurs if it is 

 neither reached by a tunnel nor connected by a drift with another shaft ; 

 this occurs in a tunnel if it has been driven too far into a mountain and no 

 shaft has yet been sunk deep enough to meet it ; in neither case can the 

 air move or circulate. For this reason the vapours become heavy and 

 resemble mist, and they smell of mouldiness, like a vault or some under- 

 ground chamber which has been completely closed for many years. This 

 suffices to prevent miners from continuing their work for long in these places, 

 even if the mine is full of silver or gold, or if they do continue, they cannot 

 breathe freely and they have headaches ; this more often happens if they 

 work in these places in great numbers, and bring many lamps, which then 

 supply them with a feeble light, because the foul air from both lamps and 

 men make the vapours still more heavy. 



A small quantity of water is drawn from the shafts by machines of 

 different kinds which men turn or work. If so great a quantity has flowed 

 into one shaft as greatly to impede mining, another shaft is sunk some 

 fathoms distant from the first, and thus in one of them work and labour are 

 carried on without hindrance, and the water is drained into the other, which 

 is sunk lower than the level of the water in the first one ; then by these 

 machines or by those worked by horses, the water is drawn up into the drain 

 and flows out of the shaft-house or the mouth of the nearest tunnel. But 

 when into the shaft of one mine, which is sunk more deeply, there flows all 

 the water of all the neighbouring mines, not only from that vein in which 

 the shaft is sunk, but also from other veins, then it becomes necessary for a 

 large sump to be made to collect the water ; from this sump the water is 

 drained by machines which draw it through pipes, or by ox-hides, about 

 which I will say more in the next book. The water which pours into the 

 tunnels from the veins and stringers and seams in the rocks is carried 

 away in the drains. 



Air is driven into the extremities of deep shafts and long tunnels by 

 powerful blowing machines, as I will explain in the following book, which 

 will deal with these machines also. The outer air flows spontaneously into 

 the caverns of the earth, and when it can pass through them comes out again. 

 This, however, comes about in different ways, for in spring and summer it 

 flows into the deeper shafts, traverses the tunnels or drifts, and finds its way 



