Jit Snotv, — On Stront:an and Barjtes. 



tion the variations of the barometer and thermometer, becaufe I have ob/ervcd that water 

 contains lefs oxygen in fummer than in winter ; and when the barometer is high (qu. low r) 

 than when low, the reafon of which is fufficiently evident. 



Bergman affirms, that fnow affords an indication of nitrous acid. If this be true, it ac- 

 counts for its effect in burning leather, and other fubftances plunged therein ; as Haffenfratz 

 has remarked, who afcribes it to the combined oxygen, with which he thinks it is faturated. 

 Is it probable that this acid (hould be formed at the moment of the congelation of the water, 

 by the concentration or mechanical approach of the parts, caufed by the cold in tlie oxygea 

 gas, with which the water is charged, and the azotic gas which may be afforded by the at» 

 mofpliere ? 



Let this be as it may, a queftion will prefent itfelf concerning this commonly fappofed ac- 

 tivity of fnow, namely, how it can, if reduced according to the aflertion of HafTenfratz, inta 

 water pofTeffing the fame qualities, prove beneficial for developing the tender embrios of 

 vegetables .' 



It feems, therefore, that from the whole confideration of the fubjeft, we are juftified in 

 concluding, that there is no reafon to believe that fnow communicates any pofitive fertility to- 

 the earth ; its good effedts muft be attributed merely to the fimple prefervation of plants from 

 intenfe cold, which,. by altering their organization, would deftroy the powers of lite. 



On certain Properties of Strontian and Baryte^. By Citizen Fau^ELIN^ 



I^INCE the method of obtaining barytes and ftrontian in a ftate of perfeft purity has been 

 difcovered; by chemifts, they have obferved feveral properties in thefe earths, analogous to 

 «hofe of the alkalis, fuch as the acrid burning tafte, folubility in water, and feparation in cryf- 

 tals, together with the change which they produce in the blue colours of vegetables, which 

 they convert into green. 



I (hall, on the prefent occafion, exhibit fome other of their properties, which 1 apprehend 

 may ferve to ihew their ftill. more ftriking refemblance to the alkaline fubftances. 



About a year and a half ago, upon analyzing a filiceous fulphate of barytes, I found, after 

 having decompofed it with charcoal, that the greateft part of the filex had been diflblved by 

 the acid I made ufe of to decompofe the fulphate which had been formed. 



I could not immediately determine the caufe of this unexpeded. event, but merely fuppofed 

 the barytes to have produced it.. 



1 have fmce made fome more direA experiments, to elucidate this qMeftion,, the refult of 

 which fliews that my fuppofition was not without foundation. 



E»periments on Strontian, 



Experiment I. Two hundred parts of ftrontian in fine powder, mixed with fixty parts 

 cf filex alfo powdered, were fubjedled for an hour to a ftrong fire ia a crucible of platina ;. 



the 



