On the Oxygen fuppofed to bt contained in Snow. iigr 



IV. 



Experiments and Obfervat'ions to prove that Snow does not contain Oxygen^ either in Solution 

 or in Combination, and that its. fertilizing ^ality does not depend on this Caufe. By Dr. 

 JOACHIN CaRRADORI DE PraTO *. 



X. HE generally-received opinion, that fnow produces fertility, is true, becaufe it is proved 

 by experience ; but 1 do not think it can be admitted in the fenfe which is commonly received. 

 I am well convinced that fnow produces this efFeft, but I conceive, as many others have alfo 

 done, that it a£ts in a negative manner only, by defending the plants in winter from a degree 

 of cold below that of freezing, and not, as is commonly thought, from its imparting any principle 

 of fertility. But Citizen Haflenfratz at prefent thinks he has confirmed this laft opinion, hf 

 a difcovery of the caufe of the phenomenon, which he thinks muft be afcribed to a quantity of 

 oxygen in combination in the fnow, which it afterwards communicates to the feeds which are 

 developed when it is converted into water, and he undertakes to prove by feveral experiments, 

 that fnow water contains much oxygen in the ftate of combination f . 



I fhall prove by inconteftable faiSts, that fnow water does not contain pure oxygen in the 

 ftate of folution or aggregate, nor in the ftate of fixity or combination ; and confequently that 

 the fnow cannot impart fertility by virtue of this principle. 



In the month of Auguft of the prefent year, I took the pureft fnow I could find, and after 

 having waflied it, I filled a fmall glafs bottle with a long neck, and when it began to diflblve, 

 I covered it with very pure oil olive, in order that it might not abforb any air from the atmofphere. 

 About fixteen hours afterwards, 1 firft removed the whole of the oil from its furface, then threw 

 in a fmall fifli, and immediately afterwards covered the water with frefli oil. When the fifli 

 entered the water it begaii to flruggle, and died almeft inftantly. I threw in another with 

 the fame precautions, and it alfo died. Laftly, I took a portion of water of the fame fnow, 

 which had been kept for the lame time expofed to the air, in a receiver with a large mouth, 

 and poured it into a fmall glafs bottle equal to the former. Into this I threw a fifh of the 

 fame fize as before, and immediately covered the water with oil olive ; but in this water 

 the fifli gave no figns of unfafmefs, and lived quietly for more than three quarters of an 

 hour. The thermometer flood at nineteen degrees of Reaumur during thefe experiments, and 

 the barometer at about 27 inches and a half. 



As I have elfewhere proved J that fifli by their refpiration in water, have the faculty of 

 abforbing all the oxygen it contains, and that they immediately die in water which is entirely 

 deprived of oxygen : I inferred from thefe experiments, that fnow water does not contain 

 oxygen ia a ftate of folution. 



* Journal de Phyfique, V. 2:6. 



f Journal Poiitechnique, IV. Cahier; of which fome account is given in our Journal, I. 144, 



J Annales de Chimie, et Hift. Nat. de Pavie, tome 5 et 14. 



Ia 



