84 NEW MIINERAL DISCOVERIES IN NOVA SCOTIA. GILPIN. 



The yield of tar per long ton was 75.7 Ibs., or 3.38 per cent. 



The following table shows its behaviour under fractional 

 distillation : 



Fractions. Temperature. 



Light oil 80-170 3.7 



Middle oil 170-230 9.8 



Heavy oil 230-270 120 



Anthacine oil over 270 43 



Pitch 67.0 



Water 2.3 



Loss .9 



As the ultimate analysis shows 1.51 per cent, of nitrogen in 

 the coal, and the .34 per cent, ammonia, 7.6 Ibs. per long ton, in 

 the gas liquor requires .28 per cent, nitrogen, it follows that 18.5 

 per cent, of the total nitrogen in the coal is converted into 

 ammonia, instead of usually 13 to 15 per cent. 



Three periods may be observed during the process of cok- 

 ing, in the composition and value of the gases given off. At 

 first the proportion of marsh gas (C H 4 ) is high but gradually 

 lessens. 



The following is the surplus gas produced during the first 

 14| hours : 



Average calorific value 685.8 B. T. U. 



Average illuminating value 14.7 C. P. 



Volume per long ton 5143. C. F. 



The oven heating gas produced during the remaining 19 hours 

 is as follows : 



Average calorific value ........ 566.7 B. T. U. 



Average illuminating value 9.0 C. P. 



Average per long ton 5247.0 C. F. 



The gas during the last few hours is very low in calorific and 

 candle power, but owing to its carrying a large per cent, of 

 hydrogen, it can after being purified, be enriched with benzole 

 or oil vapors and be added to the first gas. Practically, however, 

 the third gas is added to the oven heating gas, and the following 

 table shows the composition of the two : 



