340 DR. ANGUS SMITH ON PEAT. 



a great district where the land is already in use, simply 

 because its value would be destroyed for some time ; but it 

 could be done wherever there is fresh water and not too 

 much heat. It is well known that vegetation is an admi- 

 rable protection against the encroachments of water j but 

 peat would not suit water in rapid motion. 



However contradictory it may appear, I believe that 

 the growth of peat-bogs is a most valuable method of 

 obtaining solid dry ground in many cases ; and later I 

 purpose showing how far it has succeeded unintentionally. 

 Indeed I may say I have myself seen it done in Scot- 

 land by force of nature and neglect. 



Heating -power. 



In calculating the heating-power, it is not easy to come 

 to practical results when comparing different substances ; 

 but we can compare substances of the same character 

 well. The trials made by Mr. Alfred Fryer in my labo- 

 ratory gave Wigan coal as 14000, peat 5100 and 4850, 

 oak 9700, and deal 9300. If, then, we say that peat 

 gives half the heat of coal, we must mean very inferior 

 coal or very excellent peat. To say one third would be 

 safe in a general way, unless we knew distinctly the cha- 

 racter of the peat and coal to which we were specially 

 alluding; but with Prof. Gysser I shall say 0*4, as he 

 certainly has examined many specimens. 



Gysser' s Table of Heat produced by Wood and Peat. 



(From Professor Johnson's ' Peat and its Uses,' p. 97.) 



o 



Beech wood split, air-dried 10 



Peat condensed by Weber and Gysser s method, air- 

 dried, with 25 per cent, moisture i*o 



Peat condensed by Weber and Gysser's method, 



hot-dried, with 1 o per cent, moisture 1 '48 



Peat charcoal, from condensed peat 1*73 



Same simply cut and air-dried o*8o 



Beech charcoal 1*90 



