Intelligence and Miscellaneous Articles. 239 



astringent taste ; it is soluble in absolute alcohol, and but slightly 

 so in alcohol of density 0*85. The chrenates of the alkaline earths 

 are but slightly soluble in water, and they form insoluble sub- 

 salts. The greater part of other chrenates are insoluble except 

 the protochrenate of iron, which is very soluble. 



Apochrenic acid is but slightly soluble in water, to which it gives 

 a brownish colour. The apochrenates resemble the chrenates 

 strongly, but they are brown or black, insoluble in alcohol, and 

 combine with hydrate of alumina by digestion, forming a colourless 

 solution. By this method they are easily separated from the chre- 

 nates. 



These two acids are found in several chalybeate waters in Swe- 

 den, even when the waters are colourless. They may be separated 

 from the ochre which these waters deposit by boiling it with hydrate 

 of potash. The alkali being afterwards saturated with acetic acid, 

 the apochrenic acid is to be precipitated by acetate of lead as long 

 as a brown precipitate is formed, or a greenish one, which becomes 

 brown. The liquor afterwards neutralized by an alkaline carbonate 

 precipitates chrenate of copper in greenish white flocks, the quan- 

 tity of which is increased by adding more acetate of copper. The 

 copper is afterwards separated from the acid by means of sulphu- 

 retted hydrogen. Even ochry iron ore contains these acids. 



The waters of Porta contain these two acids in the states of 

 the chrenates of soda and ammonia. In 100,000 parts of the water 

 there were found, 



Chloride of potassium 3398 



■ sodium 0-7937 



Chrenate of soda 0-6413 



Chrenate and carbonate of ammonia .. 08608 



Bicarbonate of lime 9*0578 



magnesia 1*9103 



manganese 0*0307 



iron 66109 



Phosphate of alumina 001 10 



Silica 3-8960 



Chrenic and apochrenic acids 5*2515 



29-4-038 

 Berzelius considers the azote disengaged from the water, and the 

 ammonia which saturates the chrenic acid, as the product of the 

 spontaneous decomposition of the two organic acids ; and he attri- 

 butes the acids to the putrefaction of vegetable substances on the 

 surface of the earth, in the extensive marshy forests which surround 

 the spring. — Journal de Chimie Medicate, Arril 1834. 



SCIENTIFIC BOOKS. 

 In the Press. 

 A Guide to Geology j explaining the Elementary Facts and In- 

 ferences of that Science, with condensed Descriptions of the prin- 

 cipal Stratified and Unstratified Rocks, Tables, Plates, &c. By 

 Professor Phillips. 



