524 PEAT AND TURF 



Several trials were made to determine the amount of creosote present in the tar, 

 but, although its presence could bo recognised, its proportion was so minute as to 

 render -its quantitative estimation impossible. This circumstance constitutes an essen- 

 tial distinction between peat-tar and wood-tar, and indicates for the former an inferior 

 commercial value, as the presence of creosote, now so extensively employed, is an 

 element, in the estimate of the price of tar obtained by distilling wood. 



'It will be understood,' writes Sir Robert Kane, 'that the materials indicated in 

 the foregoing Table by the names "fixed and volatile oils" are in reality mixtures 

 of a variety of chemical substances of different volatilities and compositions gene- 

 rally carbo-hydrogens of which the further separation would be a labour of purely 

 scientific curiosity, without having any bearing upon the objects of the present report. 

 Although, therefore, those liquids were carefully examined, and observations made 

 regarding their chemical history, I shall not embarrass the present report by refer- 

 ence to them in any other point of view than as products of destructive distillation, 

 whose properties, analogous to the highly volatile and to the fixed oils repectively, 

 may give them a commercial value such as has been represented. I may remark also, 

 that, as a purely scientific question, the true nature of the solid fatty product is of 

 much interest. The name paraffin has been given to this body, but in some of its 

 characters it appears to deviate from those of the true paraffin, as described by 

 Eeichenbach to be obtained from wood-tar ; those differences, however, should not 

 contravene its commercial uses.' See PAHAFFIK. 



' The inquiry so far carried on sufficiently established that the peat, by destructive 

 distillation in close vessels, yielded the several products that had been described, and 

 were identical, or closely analogous, with those afforded in the distillation of wood or 

 coal. The process in close retorts, however, being not at all that proposed or econo- 

 mically practicable for commercial purposes, it was necessary to proceed to determine 

 whether the same varieties of peat, being distilled in a blast-furnace, with a current 

 of air, so that the heat necessary for the distillation was produced by the combustion 

 of the peat itself, would furnish the same products, and whether in greater or in less 

 quantities than in the process in close vessels. 



' For this purpose the cylinder, which in the former series of experiments had been 

 set horizontally in the furnace, was placed surrounded by brickwork vertically, its 

 mouth projecting a little at top, so that the tube for conveying away the products of 

 the distillation passed horizontally from the top of the brickwork casing to the con- 

 densing-apparatus. Near the bottom of the cylinder the brickwork left a space where 

 the cylinder was perforated by an aperture, 1J inch diameter, to which the tube of a 

 large forge-bellows was adapted. The arrangement thus represented nearly the con- 

 struction of an iron cupola. The cylinder being charged with peat, of which some 

 fragments were first introduced lighted, and the blast being put on, the combustion 

 spread, and the cover of the cylinder being screwed down, the distilLition proceeded, 

 the products passing with the current of air into the series of condensing-vessels, and 

 the gases and air finally being conducted by a waste-pipe to the ash-pit of a furnace, 

 where they were allowed to escape. 



^ By this means there was obtained, on a moderate scale, a satisfactory representa- 

 tion of the condition of air-blast distillation of peat which has been proposed as the 

 commercial process. In so carrying it on, several interesting observations were made 

 which will require to be noticed here in a general point of view. 



' First, as to the nature and quantities of the products. The specimens of peat 

 operated on were selected as similar to those employed in the former series of which 

 the results have been quoted ; and the products similarly treated were found to be, 

 from 100 parts : 



Average Maximum Minimum 



Watery products , . . 30'714 31-678 29-818 

 Tarry products . . . 2-392 2-510 2-270 



Gases 62-392 65'041 .59-716 



Ashes 4-197 7'22fr 2-493 



1 These several products having been further examined, as in the former case, gave 

 from 100 parts of peat : 



Average Maximum Minimum 



Ammonia . . . . 0-287 0-344 0-194 



or as 



Sulphate of ammonia . . I'llO 1-330 0745 



Acetic acid .... 0'207 0-268 0-174 



or as 



Acetate of lime . . . 0'305 0-393 0'256 



Pyroxylic spirit . . . 0-140 fl'158 G'106 



Volatile oils .... 1'059 1-220 (C946 



Paraffin . . 0-125 0'169 0-086 



