17 
extended application tlian the art of boring. F or ascertaining the 
position of coal-seams, and for obtaining a supply of water, bore- 
holes are frequently sunk in many parts of the country. But 
we have yet, by a comparison of the practice of different coun- 
tries, and the adoption of a more economical mode of sinking, 
where need be, to greater depths, to increase their sphere of 
utility. At Neusalzwerk, near Minden, a bore-hole has lately 
been pierced through the trias formations, to the depth of 
2,300 feet, for brine springs ; and another, at Mondorf, in 
Luxembourg, to near 2,400 feet, which, though unsuccessful in 
discovering salt, has supplied a spring of above 21 cubic feet per 
minute. At these and various bore-holes of less depth in 
Germany and France, a variety of apparatus has been employed, 
a complete study in itself, much of which has been serviceable in 
greatly reducing the time and cost of such operations. We may 
instance the ingenious instruments of M. Degousee, the “ free- 
falling” cutter of Herr Kind, and the hollow iron rods of Yon 
(Fynhausen, as a few of those which are well worthy of atten- 
tion for the good service rendered in the execution of great 
works. Again, we know far too little of the routine of the 
Chinese well-borers, who have succeeded, according to the 
detailed statements of Father Imbert, in attaining the extra- 
ordinary depth of 3,000 feet, by their simple and inexpensive 
apparatus of rope-boring, an example which has been success- 
fully imitated in the chalk districts of 1' ranee. 
The next division of importance embraces the tools used in 
mining. One of the greatest advantages which we enjoy over 
our forefathers is the use of gunpowder in rending a path 
through the harder rocks, which they with enduring and patient 
labour were obliged to cut away with hammer and wedge. But 
the implements employed in various districts differ not only in 
form and weight, but in their material and useful effect. Let me 
only allude to one point : in scarcely any of our mines, whether 
in the north or south, has it been attempted to use borers of 
steel ; iron is almost universally, with us as in most parts of the 
continent, the material of which the shank of the borer is 
composed. Yet in Saxony, for many years past, as also in 
Derbyshire, and at Ecton, the work has been advantageously 
6. JB 
