324 



DR. ANGUS SMITH ON PEAT. 



Although I believe this really happens, we cannot sup- 

 pose all the carbonic acid to be formed without a supply 

 of oxygen from the air as well as from the peat ; and Prof. 

 Johnson would no doubt say the same. 



P. 43. "In several peats, the amount of nitrogen is as 

 high as 2*4 per cent.; and in one case 2*9 was found." 

 Although he adds that some are poor and contain less than 

 half per cent., he does not give the quality of this peat. 



Of nitric acid in weathered peat Prof. Johnson gives a 

 table of analyses by Boussingault and Reichardt, in which 

 the amounts vary from o to 0*421 per cent. (p. 44). 



The ultimate composition of peat has been inquired into 

 by W. Baer ; and the results of his research, and his analyses 

 of wood, are here given. The average of his peat agrees so 

 well with one of the specimens examined in my laboratory 

 that one may consider that the composition does not greatly 

 vary from Scotland to Germany, but depends on the soil 

 more than climate. The much larger amount of ash in 

 ordinary peat is a disadvantage compared with wood. 



The following comparison is by W. Baer, in the ' Jahres- 

 bericht iiber die Fortschritte der Chemie 1847-48,' p. 1 1 12. 

 The quantity of carbon is greater than in wood ; but that of 

 the hydrogen is less. 



Carbon. 



Birch 4889 



Red Beech, ist 46-10 



, 2nd 48-29 



White Beech 48-08 



Oak 48*94 



Alder 48*63 



Pine, young 50*62 



, old 49*87 



8)389-4* 

 Average 48*677 



Hydrogen. 



Oxygen. 



Ash. 



6-19 



43*93 



099 



579 



46-87 



1*24 



6 - oo 



45' J 4 



0*57 



6 - I2 



44*93 



0-87 



5 "94 



43*°9 



2*03 



5'94 



44*75 



o-68 



6*27 



42-58 



0-58 



6*09 



43-14 



o-68 



048*34 



8)354*43 



8)7-64 



6-042 S 4- N + 044*304 



°'955 



