REPORT OF THE DIRECTOR AND STATE GEOLOGIST 1903 57 



Exter's process is employed, which consists of plowing or harrow- 

 ing the surface of the bog to the depth of about 2 inches and, when 

 the peat has become air-dried, scraping it into ridges and then 

 conveying in carts or cars to the mill. At the mill the peat is 

 screened, then put through a mechanical drier, after which it is 

 disintegrated and conveyed to the briquet machine. This press, 

 which was patented by A. A. Dickson, depends on the principle 

 " that, if a tube of indefinite length be fed with any material, the 

 resistance due to friction between the material and tube walls, 

 will gradually rise till no more can be forced in. Peat is of such 

 a nature that, when once caused to pack in the tube, continued 

 pressure on the material generates a rapid and great increase in 

 the frictiona.l resistance. For a die or tube 2% inches in diameter 

 a length of 1 foot will give a frictional resistance equal to a 

 pressure of 8 tons per square inch on the punch." Difficulty has 

 been encountered at the Welland plant from heating the die, and 

 water jackets have been used to keep the tubes cool. The con- 

 tinued use of similar processes of briquetting peat in Russia, 

 Germany and Holland, makes the difficulties here encountered 

 seem somewhat surprising. 



At the Beaverton works, the peat is excavated by a machine 

 known as the Dobson excavator, which digs the peat and spreads 

 it over the surface of the bog to dry. The peat is raked by hand 

 and scraped into piles in about the same manner as at the Welland 

 bog, after which it is taken to the mill. On reaching the mill, it 

 is passed through a '" disintegrating machine, where it is sub- 

 jected to a fierce hail of blows in order to reduce the size of the 

 fragments and destroy the minute plant cells of the peat fiber, 

 thus permitting the remaining moisture to be more readily liber- 

 ated in the drier. The machine consists of a circular sheet iron 

 box incasing a horizontal shaft from which project radial cast 

 iron arms about 1 foot in length ; through the ends of these and 

 parallel to the shaft, run iron rods, each suspending a roll of knob- 

 like, cast steel fingers, 4 inches long and free to swing about the 

 rod. The shaft makes 400 revolutions per minute, and the steel 

 fingers, flying out radially, dash the peat fragments against a 



