282 SUPERFICIAL DEPOSITS 



the jjresence of as little air as possible. The samples were not thoroughly seasoned, 

 and contained about 20 per cent, -water. 



The charcoal was, in nearly all cases, of good and even appearance, though no 

 special test was made as to its quality. 



Pboducts of Dry Distillation of some New South Wales Timbers. 



Comparing these results with those obtained from European woods, the most 

 notable difference appears to be in the smaller amount of acetic acid obtainable from 

 our timbers. 



It is of course to be borne in mhid that this material (algal jaeat) is very much 

 drier than a true peat would be, or than the samples of timber examined. This 

 would also account for the high percentage of ash in the specimen of algal peat 

 examined. The analysis of algal peat is interesting in other ways. As a rule algee 

 are high in nitrogen. In Thorp's " Dictionary of Applied Chemistry " (Revised Edition, 

 vol. i. 1912), p. 73, there is given the analyses of about ten varieties of algse in 

 which the nitrogen content averages 2 "5 per cent, in the dry matter. In the case of 

 the algal peat under discussion, the nitrogen in the dry matter only amounts to 0'44 

 per cent., or about one-sixth of the above amount. 



Another interesting point in which this substance differs from ordinary peat is 

 in the composition of the ash. In nearly all the analyses of peat ash that we have 

 access to the amount of lime is a striking feature, running from 20 to 40 per cent. In 

 the case of the algal peat this ingredient is by no means dominant, whereas the 

 sand, insoluble matter, and soluble silica accounts for nearly 80 per cent, of the ash. 

 In other analyses of peat these ingredients are either quite low in most cases, or 

 amount in exceptional cases to about 20 per cent. 



The name peat is somewhat of a misnomer, as this material is practically dried 

 alo-se, in which the organic structure is still apjjarent, and which does not possess 

 the density and fineness of structure associated with peat. In true peat the woody 

 fibre has undergone decomposition by the action of air and water. This is not the 

 case in this sample, which is simply a desiccated sample of the plant. 



