1864.] DR. T. STERRY HUNT ON PEAT. 433 



are lighted from below, and the blast applied. The heat from the 

 combustion of the peat in the lower part of the furnace serves to 

 distil the upper layers ; while the gases from the combustion, 

 together with the volatile products of the distillation, are carried 

 forward by the blast towards the condensers. 



This process was to a certain, extent successful ; but it was 

 found that when the force of the blast was augmented, in order 

 to obtain a more rapid combustion of the peat, the amount of tar 

 was greatly diminished. Thus, according to Dr. Paul, it was 

 found, by experiments in Antrim, with a furnace three feet in 

 diameter and fifteen feet in height, that when one and a half tons 

 of peat were burned in twenty-four hours, 3-1 per cent of tar 

 were obtained; with two tons in the same time, 1*8 per cent; 

 with three tons, only 0*98 ; and when nine tons were burned in 

 twenty-four hours, only two pounds of tar were obtained to the 

 ton. According to the experiments of Sullivan, Irish peat, when 

 distilled in retorts, gave from 1'5 to 3-5 per cent, being an 

 average of 2*5 per cent of tar; which furnished from 38'0 to 

 72*0 per cent of oil, the mean being 52*0 per cent. Of this oil, 

 5*0 per cent distilled below 212*^ F. ; 20-0 per cent between 

 260° and 320° ; 35-0 per cent between 320° and 550° ; and the 

 residue at a still higher temperature. Hence, as an average, 100 

 tons of Irish peat would yield 682 gallons of tar, and 333 gallons 

 of refined oils. It was found that under favorable conditions, 

 the amount of tar obtained by Mr. Recce's process was very nearly 

 equal to that produced by distilling the same peat in closed 

 retorts. 



Dr. Paul has lately undertaken a series of experiments on the 

 distillation of peat on a large scale, at Stornaway in the island of 

 Lewes ; the results of which he communicated to the British 

 Association for the Advancement of Science, at Cambridii'e, in 

 October, 1862. The mountain peat of that region is compact, 

 heavier than water, and is superior for this manufacture to ordi- 

 nary bog-peat. By distillation in a retort, it gave : tar 9-08, 

 coke 31-50, water 37-88, gas (loss) 21-54; =: 100-00. The tar 

 thus obtained was a soft solid at 60*^ F. ; it had a specific gravity 

 of -960, an acid reaction, and gave, by rectification, forty-two per 

 cent of a refined oil, boiling above 300° ; besides from thirty to 

 forty-six per cent of more volatile liquids. These, as well as the 

 ammonia, acetic atjid, and pyroxylic spirit were neglected by Dr. 

 Paul in his experiments. The refined oil contained about one 



