388 



M. Chevreul's Chemical Examination of two [April, 



§ 1. — Experiments on the Indestructible Matter of each Specimen. 



Experiments on Specimen A. 



1. 2 grammes,* exposed to 

 a temperature of 212° to 260°, 

 lost 0*1 85 gr. of water. 



2. The dried matter, heated 

 in a platina capsule, first ex- preceding (2) 

 haled an ammoniacal, oily and gr 

 hydrocyanic odour ; it then 

 kindled like a pyrophorus at a 

 scarcely red heat, and gave off 

 sulphurous acid, and after- 

 wards ceased to glow. It lost 

 in this operation 0-165 gr. 



3. The calcined matter 

 weighed 1"650 gr. ; it dissolved 

 in part in weak nitric acid, 

 with effervescence ; the resi- 

 duum weighed 0-228 gr. ; it 

 was sandy and coloured, it was 

 separated by the filter. 



I. Saudi/ Residuum. 



4. Ignited with potash in a 

 silver crucible, the fused mass 

 was not coloured green ; it 

 was dissolved in water and 

 muriatic acid ; by evaporation 

 and water 0-159 gr. of silica 

 was separated from the solu- 

 tion. 



5. The liquid from which the 

 silica had been separated gave 

 a precipitate, which, by means 

 of potash, afforded 0-026 gr. 

 of alumina, and 0-013 gr. of per- 

 oxide of iron. 



6. The ammoniacal liquid 

 mixed with oxalic acid gave ox- 

 alate of lime, equivalent to 

 0-005 2;r. of lime. 



Experiments on Specimen B. 



1. 2 grammes lost at the 

 same temperature 0-210 of 

 water. 



2. Same phenomena as the 

 the loss = 0-2 



3. Same phenomena ; sandy 

 residuum = 0-237 gr. 



I. Sand^ Residuum. 

 Same phenomena ; silica 



= 0-185 gr. 



5. Same phenom-?na ; alu- 

 mina = 0-04 gr. ; peroxide of 

 iron = 0'013 gr. 



6. Same phenomena ; lime 

 = 0-02 gr. 



II. Nitric Solution. 



7. Precipitated by ammonia 

 and the precipitate washed 



II. Nitric Solution. 



". Same phenomena ; preci- 

 pitate = 0-635 gr. 



The Weights are m granunes ; the degrees of heat are those of Parenheits* scale* 



