MECHANICS AND USEFUL ARTS. 47 



^ The paper read last year before the British Association by Civil 

 Engineer Clark, of London, contains important fticts relative to 

 peat.^ A large establishment is engaged in making it in England, 

 and its trial on two of the British railways proved that it main- 

 tained a higher and better head of steam than coal did, that better 

 time was made, and that, pound for pound, it was a saving both 

 of time and money to use peat in locomotives. 



The machine of which we have spoken may be worked by 

 steam or other power. It receives the crude peat just as it is 

 taken from the bog, condenses it, and in a very few minutes de- 

 livers it in the form of bricks, which may then be exposed in the 

 open air or under shelter, to dry or cure. 



There are vast beds of peat in New England and New York, 

 and it behooves our farmers to avail themselves of it, and thus, 

 while turning " uniirofitable " land to account, preserve their 

 forests, which are now rapidly used up for fuel, till better uses can 

 be found for them. 



IMPROVED MACHINERY FOR WORKING GOLD AND SILVER ORES. 



Messrs. Whelpley and Storer, of the Boston Milling and Manu- 

 facturing Company, have introduced machinery for the pulveriza- 

 tion of gold and silver ores, in which mechanical principles are 

 applied that have never before been employed for such a purpose. 



The ores are broken, in the first instance, by the rapid 

 movement of a circular iron table, a mass of metal 3h feet in 

 diameter, weighing 800 pounds, making 1,025 turns per minute. 

 The table itself forms the bottom of a cast-iron tub, 18 inches 

 in depth, of which the sides are grated, or perforated with small 

 openings. The entire structure, except the upright shafts upon 

 which the table revolves, is of cast-iron, the wearing parts 

 being of what is called Franklinite iron, which is so hard that 

 it cuts glass. The upper surface of the whirling- table, or bot- 

 tom of the tub, is furnished near its circumference with several 

 blocks, called cutting or splintering blocks, also of Franklinite. 



The material to be broken, being fed into the tub through the 

 hopper, drops until its lowest point receives a shivering blow 

 from the upper edge of the rapidly-revolving blocks, by which it 

 is constantly thrown upwaixl and outward against the sides of the 

 cylinder, being i-eflected back upon the blades until it is-suificiently 

 comminuted to pass through the perforations into the surroundhig 

 box or chamber. 



The weight of the table, with its case, shaft, frame, cutters, 

 etc., complete, and packed ready for transportation, is about 

 3,600 pounds. 



An average of twelve-horse power is allowed, in practice, for 

 the full work of a whirling-table. 



The whirling-table is more rapid in its action than any other 

 machinery for cutting or breaking. It is callable of reducing 

 more than 200 tons of ordinary quartz, in pieces from three or 

 four inches in diameter, to coarse gravel size, in twenty-four 

 hours. It lias reduced eighteen tons of quartz into gravel, in one 

 houi-, through three-quarter-inch holes. 



