4-22 31. Pesckier's Physico-chemical Inquiry into [June, 



Twenty-five parts of this residue, treated by nitro-muriatic acid 

 were found to be composed of 



Siliceous substance .... 1418^ 



Peroxide of iron 3-25 i rn • r i.i. 



., • 1 r-r Ine uicrease or the 



A uninia r /5 ' 



Chalk 0-10 i> 



Resinous principle 3*20 



Organic ditto 2-25 



Ditto, ditto, soluble , . . . 1 •75_ 



26-48 



'vveight can only be 

 ascribed to the in- 

 terposed water. 



The water in the bottle No. II. was from a red snow, which is 

 met with on the edge of the great masses of white snow ; its 

 colour was not so bright as that of No. I. and it did not change 

 in melting. 



This water, of which there was but a small quantity, was con- 

 tained in a narrow bottle, the sixth part of which was filled with 

 a brown and heavy deposit : when filtered, it retained a bright 

 yellow colour, and left a residue, weighing, when dry, 48 grs. 



This water stained the test papers red, by the effect of the 

 carbonic acid ; it gave, with the above-mentioned tests, liquids 

 more coloured than that of No. I. and the oxalate of ammonia 

 acted more powerfully upon it. 



The residue had a brown tint ; it was rough to the touch, and 

 sprinkled with small fragments of rock crystal : alcohol and 

 water had no sensible effect on it ; the first furnished by its eva- 

 poration a small quantity of a yellow tincture ; exposed to a 

 brisk heat, it emitted neither smoke nor smell ; treated by nitro- 

 luuriatic acid, 25 parts were composed of 



Silex 1-25 



Peroxide of iron 12*34 



Chalk 0-20 



Organic substance and water. 10*00 



23-79 



The results of these different analyses seem to indicate that the 

 ved colour of the snow found in summer on some elevated parts of 

 the Alps, arises from two different causes ; viz. first, from a greater 

 or less quantity of oxide of iron spread over its surface in a very 

 jrreat state of division, and in a very high degree of oxidation ; 

 secondiv, from a resinous vegetable principle, of an orange- 

 ved colour, belonging, according to all appearance, to some 

 cryptogamous plant of the genus alga, or lichen. And as 

 jiature presents us with a very great number of vegetables in 

 which iron exists in prstty large quantity, it does not seem to be an 

 ina.dt!iissible supposition, that this iron formed, perhaps, one of 

 tJie immediate principles of the vegetables in question, of which 



