70 ANNUAL OF SCIENTIFIC DISCOVERY. 



ing in molten iron which fills every interstice between and around the 

 stones a conglomerate block can be formed at an expense of about 

 two dollars per cubic foot, and of any required shape for interlocking ; 

 while, by means of cores, it may be furnished with all treenail holes, 

 recesses for joggles, grooves for wedges, and for any species of band or 

 attachment that can be devised. The granite not being disintegrated 

 by the contact of the metal, which latter has a continuous honey-comb 

 structure, the conglomerate has great power of resisting compression, 

 andoilso great tensile strength, the two qualities which give it value 

 in this connection ; its strength being as a cellular block of iron, with 

 its cavities so filled with granite as to preserve its chambers from being 

 crushed in. The cost of the conglomerate will vary in different places ; 

 the refuse of the granite quarry is what is required, and iron of suffi- 

 ciently good quality for this purpose may be had at low rates. The 

 proportions of the materials may likewise be varied according to the 

 purpose to which it is applied. They may be as follows : 



Granite . . 150 Ibs. . . occupying \ of a cubic foot. 

 Iron, ... 150 "... " i " " " 



300 " . . . " 1 cubic foot. 



Estimating the iron at twenty dollars per ton, and the granite at six 

 dollars sixty-six cents per ton, the cost of the conglomerate would be 

 two dollars per cubic foot. There are 13,147 cubic feet of stone in the 

 Eddystone, and 28,530 cubic feet in the Bell Rock ; the cost per cubic 

 foot in the former being about six dollars, and in the latter, seven dol- 

 lars and fifty cents per cubic foot. Appleton's Mechanic's Magazine. 



A MACHINE SUBSTITUTE FOR THE RAYS OF THE SUN. 



THE London Mining Journal for December 8th contains drawings and 

 descriptions of a machine, which, for novelty of purpose, has not, we 

 think, been surpassed. This invention is intended to be a " substi- 

 tute for the rays of the sun," by burning the stubble, roasting the soil, 

 and mixing together the ground thus heated with ground not heated. 

 The inventor, M. Hartrig Von Blucher, proposes to effect this by 

 means of a cylinder, composed of iron ribs, at the axis of which is sus- 

 pended a semi-cylinder. The latter serves as a stove to warm the 

 large cylinder and keep up the heat in it. This cylinder, acting as a 

 wheel or roller, is to be drawn over the stubble, which, by the heat 

 communicated, will be consumed, and the ground roasted. For the mix- 

 ture of the roasted soil with the deeper strata, it is proposed to have 

 a second cylinder, attached to the same frame, follow the first cylinder. 

 The ribs of this second cylinder have curved spades attached to them, 

 in order to dig into and mix the earth. A coal -box, to supply fuel to 

 the stove, is attached to the top of the digging cylinder, and, by 

 increasing the weight of the cylinder, the spades work more effect- 

 ively. The stove referred to, being freely suspended from the axis, 

 constantly maintains an upright position as the cylinder revolves. 



