252 Intelligence and Miscellaneous Articles. 



These results, M. Marchand remarks, agree with the formula ad- 

 mitted for formic aether [acid?], and are confirmed by the specific 

 gravity.— JowrwaZ de Pharm., Juillet 1839. 



ANALYSIS OF HAILSTONES. BY M. GIRARDIN. 



In a letter addressed to M. Arago, and read at the Academy of 

 Sciences, on the 22nd of April last, M. Girardin gives the results 

 df the analysis which he has made of hailstones collected in the 

 month of February preceding ; the following details are extracted 

 from the latter. 



The hailstones, collected with the requisite precautions, were in- 

 troduced into a bottle washed with distilled water, they weighed 

 about 500 grains ; the hail readily melted, and the liquid had the 

 appearance of water into which a few drops of milk had been suf- 

 fered to fall; it was turbid and whitish. Gradually there were 

 formed in it a considerable abundance of white and very light flocks, 

 which soon formed into one cloudy mass, and deposited at the bot« 

 torn of the vessel. The next morning, the liquid was perfectly 

 limpid, 



A portion of the water, whilst it was still whitish and milky, was 

 put into a glass, and a few drops of nitrate of silver were added to 

 it. The glass, stopped with paper, was placed in the dark and al- 

 Iqwed to remain for twelve hours. The addition of the reagent pro- 

 duced no apparent effect, and the liquid preserved its original aspect 

 without becoming coloured. On being afterwards put into a place 

 brilliantly lighted, it became almost suddenly reddish; then in 

 about an hour, it assumed a brown colour, and deposited grayish 

 flocks, and brilliant white pellicles were at the same time formed 

 on the surface. The flocks, separated from the liquid, were calcined 

 in a small glass tube ; they emitted a smell of burnt animal matter, 

 and reddened litmus paper was rendered blue by exposure to them. 

 There remained at the bottom of the tube a grayish powder, which 

 was a mixture of charcoal and metallic silver. 



The greater portion of the hailstone water was evaporated while 

 turbid and milky, cautiously in a platina capsule. During the eva- 

 poration, no trace of ammonia was perceptible ; the residue was of 

 a yellowish brown colour, but the quantity was so small that the 

 weight could not be determined, A similar evaporation having 

 been made in a glass tube, the residue was heated to incipient red- 

 ness. It exhaled during calcination a very sensible odour of am- 

 monia, and reddened litmus paper was rendered blue by it : there 

 remained a trace of charcoal at the bottom of the tube. 



Hailstone water filtered and clear became slightly turbid with 

 oxalate of ammonia, and more so with nitrate of barytes, and nitric 

 acid did not restore the transparency. No other reagents produced 

 any efi"ect. In the small quantity of this hailstone water which I 

 had, I could not discover the existence of nitric acid. 



It follows from what has been stated that the hailstones examined 

 contained a considerable portion of organized and azotized jnatter, 

 a sensible quantity of lime and sulphuric acid, but no sensible trace 

 of ammonia. 



