110 TECHNOLOGY. 
preparatory arrangement of the ground for boring, where the hole to be 
bored is to be six inches in diameter. The frame has four posts, some 12 
feet high, and stands over a shaft about 9 feet in depth, which has been 
sunk at the commencement of the operations, in the axis of which a wooden 
tube is placed to guide the auger at the outset. The rope passes over a 
guiding pulley of oak which hangs above the frame, and is wound up 
around the axis of a windlass, for which a vertical capstan is substituted 
when the hole becomes deeper. The longer arm of the lever is 12 to 
15 feet in length, and the shorter 2 to 3 feet; the latter terminates in a 
rounded head which serves to raise the rope with the auger. In order to 
keep the auger rope always taut, the longer arm of the lever is provided 
with a hook by which it may be fastened down. 
The boring instruments used consist of a simple chisel which is fastened 
on the lower end of an iron rod (jig. 8, front view; jig. 9, sectional view), 
which hangs to the rope by means of a swivel. In the middle it is square, 
but above and below it has a round flange with four incisions, by which the 
borings may pass up. The diameter of the flange is equal to the width of 
the chisel. The hook (pl. 23, fig. 33) is used to give a twisting movement 
to the rope. A comparison of rope with rod augers shows that in boring a 
hole 18 inches in diameter and 200 or 300 feet deep, the cost with the rope 
auger is greater than with the rod auger, and that in using the latter the 
cost increases greatly with the depth, while with the rope auger it remains 
nearly unchanged. 
2. Mininea For ORE. 
The tools of the miner differ according to the nature of the stone or soil. 
Tn loose substances, such as sand, gravel, marl, &c., he uses a heavy pick with 
a blunt point. In soft adhesive substances like peat he uses a cutting tool like 
a gardener’s spade, but which is furnished on the sides with two wings, so that 
the separation of the peat from the mass is rendered easy. This is shown 
in pl. 23, fig. 28a. For digging many mellow substances, such as clay, 
sand, and decomposed rocks, the pickaxe, crowbar, and shovel are suf 
ficient. The pickaxe used, at one end terminating in a steeled point, and 
with a handle about 23 feet long, is represented in jigs. 14 and 15. The 
size of the iron part is proportioned to the stone to be worked. In working 
mineral coal the miner makes a deep furrow or trench in a certain part of 
the mass to be obtained. The trenching tool is a light pointed sharp pick- 
axe ( pl. 23, figs. 16 a and 17a), having the helve in the middle. For hard 
stone a heavier tool is used. PJ. 24, fig. 41, shows the miner at work with 
the pickaxe in soft stone. 
Hard substances are obtained by the mining pick or by the aid of fire. 
The pick (pl. 23, fig. 19) is a tool of iron faced with steel or made entirely 
of steel. On one side it ends in a point of the form of a four-sided rectangu- 
lar pyramid, and on the other has a flat face. The eye of the helve is in 
the middle. The miner (pil. 24, fig. 42) places the point of the pick on the 
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