SOLID FUELS. 79 



cent. It even varies in the same locality and in the same 

 bed. In burning lignite there is considerable loss in the waste 

 gases on account of the large quantity of air introduced, and 

 also from the moisture carried off from the fuel. 



Brix published the following results with dried lignite : 



Water Evap- Per cent 

 orated. Ash. 



Lignite of Aussig, Bohemia 5.8 pounds 15.0 



" Perleberg, " 5.6 " 6.0 



" " Goldfuchs n. Frankfort... 5.5 " 9.1 



" " Rauen 5.4 " 6.3 



Bunte used two kinds of lignite in boiler-tests, and gives 

 the following results : 



Neusattel. Chodan. 



Calories in steam 42.8 49.2 



" "gases 19.6 21.0 



" " aqueous vapor 9.2 8.7 



" "ash 9.0 6.1 



" unaccounted for 19.4 15.0 



The grate used was a step grate (Treppen-Rost). 



The lignite used on the railways in Italy contained 15 

 per cent of water, and gave a yield of heat equal to one half 

 its weight of coal. 



Analogous to the lignites are certain shales or fossils 

 carrying bitumen. They are sometimes termed boghead 

 cannel, bituminous schist, etc. They are distilled in some 

 localities for oil, but are not much used as fuel. 



Bunte determined the heat of combustion of a sample 

 from Australia, and analyzed one from Scotland. 



Carbon. Hydrogen. O -f N. Calories. 



Boghead shale, Australia. 83.17 10.04 6.79 9134 

 Scotch Boghead 81.54 11.62 6.84 



