88 ANNUAL OF SCIENTIFIC DISCOVERY. 



forming rectangular slabs. To supersede this slow method of quarrying slate, 

 H. J. Bremner, of Nazareth, Pa,, has invented a machine, in which cutters 

 are operated so as to feed forward and cut out a groove hi one direction, the 

 desired length, and then it (the machine) is turned, and the cutters made to 

 cut a transverse groove, and thus proceed until the rock is so grooved that 

 the space between the side and two end grooves or cut channels, forms a slab 

 of the size desired for the slate; the slate is then forced out, and splits easily 

 into as many separate slabs as there have been horizontal layers from the sur- 

 face to the depth the cutters have perforated. One of these machines, it is 

 asserted, when operated by hand, and with one man, will cut out more slate 

 in one day than twelve men with picks by hand labor. 



Machine for Cutting and Trimming Slate. A machine for cutting and trim- 

 ming slate has been invented' and patented by Asa Keyes, of Brattleboro', 

 Vermont. The nature of the invention consists in applying a rapid succession 

 of stone hammer blows, each of which beats off a minute piece of the slate 

 while it (the slate) is carried along by a carriage on ways. The wheel which 

 carries the hammers or cutters is heavy, and this weight of the wheel not only 

 furnishes the momentum of the individual blows of each hammer, but supplies 

 the purpose of a fly-wheel to the machine. The hammers are held into mor- 

 tises cast in the wheel, by bolts and nuts. Fifteen of these machines are used 

 by the New England Mining and Quarrying Company, at Guilford, Vermont. 

 They have greatly reduced the cost in trimming and cutting of slate. A de- 

 tailed description of this machine, with diagrams, may be found in the Scien- 

 tific American, February, 1853. 



HYDRAULIC ROCK DRILL. 



In this invention by Mr. J. Echols, of Georgia, the drill-rod is provided 

 with two cup-shaped collars, the hollow sides facing toward each other. A 

 line of hose leads from an elevated reservoir and throws a stream first upward 

 against the upper cup, then downward against the lower one. The force of 

 the water thus applied keeps the drill continually leaping with great force ; 

 and considerable ingenuity is displayed in working out the details so as to 

 secure the fullest effect of the water, properly rotate the drill, and make the 

 position of the cups and of all the parts self-adjusting as the drill penetrates 

 into the rock. The simplicity, lightness, and portability of this machine con- 

 stitute its chief advantages, and these are so important as to make practicable 

 the employment of this drill, even where a steam-pump must be employed to 

 impel the water. There is a loss of effect in the transmission of power in this 

 manner, similar in kind to that of using water by an undershot or a turbine 

 wheel J but, rightly managed, this loss may be reduced to a very small per 

 centage, and the difference between the stretching a hose across a ledge, and 

 the arranging of cumbrous machinery with belting or shafting, is sufficiently 

 great to atone for many inconveniences. 



IMPROVEMENT IN BLASTING ROCKS. 



An improvement in blasting rocks, recently patented by Capt. C. F. Brown, 

 of Warren, R. I., consists in placing the powder or charge within a tube or 



