296 M. Chevreurs Chemical Examination, 3fc. [April,' 



(21), and azotized organic matter, which had probably suifered 

 -.ilteration. I have every reason to think that the two last sub- 

 stances formed a kind of hike with the alumina and peroxide of 

 iron. The residnnm heated in contact with the air burnt like a 

 pyrophorus, and the cinder which it left was much less coloured 

 than itself. By distillation it yielded a slightly acidulous water, 

 oil, sulphuretted hydrogen without sulphite of ammonia, carbon- 

 ate of ammonia, a product possessing the smell of hydrocyanic 

 acid, but whicli did not produce prussian blue ; and lastly, a 

 bulky black residuum. 



2. Sand^ Matter. 



43. The nature of the sandy matter was analogous to that of 

 the pulverulent matter, with this difference, that it contained a 

 larger proportion of phosphates, and a smaller proportion of 

 yellow organic matter, alumina, and oxide of iron. It burnt 

 when heated in the air, but not so well as the pulverulent mat- 

 ter. By distillation, it yielded ammoniacal water, sulphuretted 

 hydrogen, carbonate of ammonia, and a black residuum which 

 was a pyrophorus when heated ; the strong smell of the product 

 occasioned an examination for hydrocyanic acid, but none was 

 found ; the small quantity of the matter did not allow of any 

 examination for cyanogen. 



Conclusions. 



I. The organic matter of the soil of the cave of Kuhloch, de- 

 structible by fire, is formed of 



1st. A fatty acid, which in my examinations presented the 

 properties of stearic or margaric acid. 2dly. A fatty matter 

 which was not acid. 3dly. An organic acid soluble in water. 

 4thly. A yellow colouring principle. 5thly. A brown azotized 

 matter. 



A portion of the yellow colouring principle and of the azotized 

 matter is certainly combined with alumina and peroxide of iron. 

 It is probable that another portion of the organic matters is 

 united with the subphosphates and the subcarbonates of lime 

 and magnesia ; it is also probable that in this latter part, there 

 is proportionally more azotized matter than in the former. 



There is more organic and pulverulent matter in the specimen 

 taken from a depth of six feet, than in that from a depth of only 

 two feet. 



II. There is in the soil some chloride of potassium and 

 ammoniaco-sulphate of potash. Consequently the chloride of 

 potassium and the sulphate of potash arising from the decompo- 

 sition of the ammoniaco-sulphate of potash by heat, which 

 could not be collected in the process adopted in the analysis of 

 the incinerated soil, must augment the loss occurring in the 

 analysis. 



