COAL AND IRON OF CUTTACK. 27 



Further, the amount of timber which may fairly 



Amoiintof timber per 



acre, &c. as yet iinaaeer- be looked for as the annual supply from a given 



tained. 



area is as yet in this country unknown. 



Supposing it to be equal to that of well cared-for forests in Europe 



the out-turn per acre may be calculated at about 

 Probable average. 



8 tons of kiln-dried wood* (from 65 to 12 tons.) 



If intended to yield a continuous annual supply, about one-eighth of this 



amount may be obtained, or about 1 ton of dry wood per annum. 



The yield of charcoal which might be obtained from thoroughly 

 dried wood, as determined by Mushet, varied from 

 woli^*^"^ charcoal from 26-0 per cent, from lignum vitse to only 164 per 

 cent, from Scottish pine ; the average of his 

 experiments giving (from 15 varieties of wood) 22'4! per cent. We may 

 take I think safely the average of the harder varieties and say that the 

 yield would be nearly 25 per cent., that is, that one acre of land would 

 yield an annual supply of 025 of a ton of charcoal. One square mile 

 therefore, supposing it to be equally covered with forest, would yield 

 (640 acres) 160 tons of charcoal. 



As I have said, this estimate can only be taken as rudely approximate. 

 I beUeve it to be under the truth ; and that, under any fair system 

 of conservancy and of charcoal-biirning, the out-turn would be 

 greater. 



We may therefore, I think, say 200 tons per square mile. For the 



Probable yield of char- production of One ton of wought iron, on the 

 coal per sriuai-e mile. EngUsh system, three tons of charcoal wUl, ou 



the average, be required. I mean, of course, to reduce it and convert 

 it into malleable and marketable iron. If the systems I have alluded 

 to be adopted, less than 2 '5 tons will be amply sufficient. In other 

 words, one square mile of forest will yield an annual supply of charcoal 



* The moisture in wood was found by Hartig to vary from 18'6 per cent, in hornbeam 

 up to 51 '8 percent, in black poplar. (The average of 22 varieties giving 38 '7 per cent.) 

 The produce of an acre therefore is now generaUy calculated in kiln-dried wood, to avoid 

 the uncertainty arising from this great variation in the amount of water in the timber. 



