434 THE CANADIAN NATURALIST. [DeC;.. 



tenth its weight of paraffine (equal to four per cent of the crude- 

 tar). About one half of the oil boiled at a temperature between 

 330° and 500° F. ; it burned without charring the wick, had but 

 little odor, was not explosive at ordinary temperatures, and com- 

 pared favorably with refined petroleum. The remainder, which 

 boiled between 500° and 600° F., had a specific gravity of -850, 

 and, when mingled with fat oils, was an excellent lubricator. 



In his early attempts to work this peat on a large scale, by 

 distillation in brick furnaces or kilns, Dr. Paul substituted for the 

 blast the draught of a chimney ; but in this way he was unable 

 to obtain* more than three per cent of tar, instead of the nine per 

 cent which the same peat furnished when distilled in retorts. It- 

 was found, moreover, that, on an average, only about fifty tons a 

 week were distilled in each kiln ; while in order to give a profit- 

 able return it was necessary to work about seventy tons weekly, 

 and to obtain five per cent of tar. His apparatus consisted of^ 

 cylindrical brick chambers, five feet in diameter and twelve feet- 

 high ; furnished at the bottom with a fire-grate having an area of 

 two feet, and at the top with a hopper and lid for feeding. Ten 

 of these kilns were built side by side, in a block; and from the- 

 top of each, a pipe of twelve inches in diameter led to a main of 

 three feefc, and thence, ' through a condensing apparatus, to a 

 chimney. In order to secure a regular current of air through the 

 apparatus, a draught was finally established by means of a thirty- 

 inch fan, of Schiele's patent, making 1600 revolutions a minute, 

 and driven by an eight-inch steam-engine ; which worked at the 

 same time some pumps, and a winding-drum by which the peat 

 was drawn up an incline to the kilns. This fan was capable of 

 passing 2000 cubic feet of gas per minute, and of maintaining a 

 steady powerful draught through seven inches of water, without 

 raising the combustion at the fire-grate of the kiln to a greater 

 extent than was desirable. By this means the vapor was rapidly 

 drawn from the kilns, and was passed several times through water, 

 and also through four chambers filled with bundles of heather. 

 This contrivance was found eff"ectual to separate the tarry matter 

 mechanically suspended and carried over by the current of gas. 

 This, when discharged from the fan, was highly inflammable, and 

 was led by an underground tunnel to a proper furnace ; where it 

 burned with a flame from six to ten feet high, six feet long and 

 six inches thick, and was available for generating steam, distilling 

 tar, evaporating liquids, or drying peat. It was found that the 



