COAL AND IRON OF CUTTACK. 2S 



course be remedied at once, and a few trials carefully and accurately 

 conducted would soon show the proper rate of combustion to attain the 

 maximum useful effect. 



The relative per-centage of charcoal obtained by quick methods, and by 

 slow methods of charring, varies with the same timber not less than from 

 9 to 12 per cent.* 

 Another question regarding which we really know nothing bearing on 

 Amount of moisture ^^^ country is the amount of moisture, which 

 absorbed unknown. ^^^ charcoal produced from the woods of India mil 



absorb after manufacture within a given time ; and yet this, consi. 

 dering the very great moisture of the atmosphere in these countries, 

 is an important consideration. 



This, in Europe, has been found to vary, in the same time, from 080 

 per cent, (beech charcoal) to nearly 9 per cent, (fir) and even to 16'30 

 per cent, (black poplar.) The total quantity taken up in nearly three 

 months varied from 10 to 12 per cent., and there can be little doubt that 

 either this quantity would be materially increased, or the time required 

 for its absorption would be considerably shortened in moist climates. 

 The amount of ash also, and the composition of that ash in the several 



varieties of charcoal, which could be procured in 

 Amount, composition, .... . , 



&c. of ash of charcoal, any quantity m this country, is unknown. Ihe 



amount of such ash, where it has been ascertained, 



is found to vary 'from much less than 1 per cent, to about 3-50 ; in some 



case even reaching as high as 6 and 8 per cent, but yielding a general 



average, on a large number of experiments, of 1'65. As I have above 



shown, the composition of the ash, no less than its amount, will exercise 



* Oak, quickly charred, gave 15-91, slowly charred 25-71 per cent. 

 Beech, „ „ ,, l-i'15 „ „ 26-15 „ 



Birch, „ „ „ 12-20 „ „ 24-70 



Pine, „ „ „ 13-75 „ „ 25-95 



And the list might be greatly enlarged. See Karstcn and Winkler's Experiments quoted 

 in Bonald's and Bichardson's Technology, Vol. I., p- 60, 



£ 



