144 SILVER MINES OF AXDREASBERG, 



calling our attention to the apparatus for supplying the mines with fresh 

 air. Some three hundred and fifty feet below ground, he showed us a 

 large wooden box, into which a wooden tube, perhaps ten inches square, 

 coming down through a vertical shaft, was closely set. This box, he 

 told us, was half full of water, and the tube ran down into it, nearly to 

 the bottom of the box. A stream of water, falling from a height into 

 the funnel-shaped mouth of the tube above ground, carries down with 

 it a considerable quantity of air, which, forced by the constantly de- 

 scending column into the iron-bound box below, rapidly accumulates 

 there. By its elasticity, the water is driven off through an opening in 

 the side of the box, which is so high up, however, that the air is first 

 powerfully compressed, and the whole is so arranged, that, whilst the 

 air in the upper part prevents the water from rising above its place of 

 egress, the air itself is forced out with an impetus sufficient to carry it 

 to the most distant parts of the mine. 



"Now, Mr. Guide, do tell us what becomes of all this water? It is 

 easy enough for water to get into such a place as this, but how do you 

 get it out again .'" " We make tunnels for it and then let it find its own 

 way out." Some of these tunnels are immense undertakings. It is 

 either at Andreasberg or at Clausthall that it was necessary to run a 

 shaft three miles before they found an exit. This is owing to the depth 

 of the mines, some of which extend three thousand feet and more, pei'- 

 pendicularly. 



In our subterranean perigrinations we next stumbled upon the eleva- 

 ting apparatus. There are two separate works of this kind, one for the 

 ore, the other for the workmen. The elevator is a simple endless rope, 

 revolving upon wheels above ground, and at the foot of the large central 

 vertical shaft. But the other is a more complicated apparatus which I 

 fear I cannot satisfactorily describe. But still I will make the attempt. 

 Two cables of iron wire are suspended side by side, eighteen or twenty 

 inches from each other, in a shaft that inclines very little from the per- 

 pendicular. At intervals of twelve feet, small boards, from six to eight 

 inches square, are securely fastened to these cables, at right angles to 

 the line of their direction. Four feet above these, bars of wood about 

 a foot in length, are lashed across the cables. Now, when the apparatus 

 is at rest, these foot-boards and hand-holds are all precisely opposite to 

 each other. But when the huge water-wheel above makes one-fourth 

 of a revolution, the one cable is elevated and the other depressed twelve 

 feet; so that any two of the foot-boards that were a moment before 

 close together, are now twenty-four feet apart, the one has risen, the 

 other descended twelve feet. The one which ascended has come into 



