54 THE YEAR-BOOK OF AGRICULTURE. 



apparatus, -which then follow at a more mpderate rate of descent, and again take hold of the 

 chisel in order to raise it for another blow. Nothing but actual experience can show the im- 

 portant effects accomplished by the free falling of the chisel. In the first place, it enables the 

 great mass of iron rods to be replaced by others of a lighter construction, as they are much 

 less severely handled in this than in the old process ; wood is the material accordingly em- 

 ployed, "which, by reason of its buoyancy in the water, is comparatively of little or no weight 

 on the lever, even in the deepest boring, provided water be present ; the labor or power is 

 consequently greatly diminished, as by Mr. Kind's process the weight to be raised each time 

 is merely that of the chisel, together with the &mall amount of counterpoise necessary to 

 keep the rods down in the water, while the whole weight of the chisel becomes effective in its 

 fall. A much more important advantage of the use of the free-fall apparatus, however, arises 

 from the less liability it occasions to those serious accidents from the breakage of the rods in 

 the hole always attending upon works of this nature under the old mode, when of any con- 

 siderable extent. This will be readily understood from what has been stated of their not 

 having to sustain those severe shocks and concussions, and also from their always being in a 

 position of suspension from the point of support on the end of the lever, and never resting on 

 their lower end in the bore-hole, whereby they are liable to be buckled up or broken from the 

 superincumbent weight of the upper on the lower portion. 



"The objection to the old system of continuous rods is thus very correctly stated by M. 

 Degousee, in his treatise Guide du Sondeur 'When borings are very deep, the weight of the 

 rods prevents the boring tool acting by percussion, and yet there are no other means of pene- 

 trating hard rocks. The instrument runs the risk of breaking frequently ; besides, to act by 

 percussion, the instrument must be raised from 3 to 4 inches, and when then allowed to fall, 

 is subject to a tremulous motion between each shock, which lashes it violently against the 

 sides of the bore-hole. This tremulous motion, repeated from 12,000 to 15,000 times per 

 day, and during many months, entails the deterioration of the retaining tubes ; and, if the 

 bore-hole is not tubed, makes the hole oval in soft places, giving rise to crumbling in ; and the 

 fragments occasionally press angularly against the tool in such a manner that the rods break 

 by the efforts necessary to extract them.' 



"We have here, accurately described, one of the principal causes which have hitherto pre- 

 vented borings of very great depth becoming common, the breakage of the rods entailing such 

 serious consequences that attempts have been frequently abandoned after a considerable 

 expenditure of labor and money. Mr. Kind's free-fall apparatus remedies this objection by 

 avoiding all those shocks and lashing of the rods ; and, while it renders the operations more 

 likely to be carried to a successful termination, removes one great cause of accident and 

 failure. 



" The core-boring is managed by having a sort of crown-tool, which cuts all round the 

 periphery of the hole, leaving an annular space and solid central block or core, which core is 

 broken off and brought to the surface by means of a particular form of clack. Instead of 

 bringing up powder for examination, this apparatus then can produce a cylindrical block 

 of the rock which is being bored through, as we have seen in the specimen cores, giving all 

 the indications in the dips of the beds and their exact character that could be obtained by the 

 sinking of a shaft. This operation requires considerable care, in order to realize to the full 

 extent the advantages to be derived from the exhibition of a perfect sample, by showing the 

 direction and amount of the inclination of the bed or strata; that it is effectually accom- 

 plished is satisfactorily established by some cores brought up from depths exceeding 1000 

 feet, as well as by the public accounts of the numerous and very extensive works that have, 

 during the last 10 years, been successfully completed under Mr. Kind's system and direction. 



" Mr. Kind has also successfully applied his system of boring to the sinking of shafts of 

 large diameter, and in certain localities, with economy. He avoids pumping during the ope- 

 ration ; and if, as is most frequently the case, large feeders of water are confined to certain 

 beds, he stops them back by means of wooden tubing. When a comparatively small power 

 only is required to keep the works dry, the operation is carried on by means of two small 

 engines, of from 10 to 12 horse-power each one arranged for winding up the rods when the 

 tool must be lifted, the other for boring. Mining Journal. 



