224 ANNUAL OF SCIENTIFIC DISCOVERT. 



PRODUCTION OF NITRATE OF AMMONIA BY AIR AND WATER. 



M. Schb'nbein has shown that nitrate of ammonia is formed at the 

 expense of air and water during the slow combination of phospho- 

 rus. He has likewise proved that this salt is present in meteoric 

 waters, and has thence concluded that its formation must be due to 

 a very general cause. He now announces that this cause is found in 

 the simple fact of the volatilization of water in free air, and he cites 

 many experiments which confirm this belief. The process which suc- 

 ceeds the best is to cause water to fall drop by drop in a metallic 

 vessel heated above 100 C., without, however, reaching the point 

 at which the liquid passes into the spheroidal state. By holding a 

 cold flask above the vapors which are produced, he condenses enough 

 water to recognize the presence of nitric acid and ammonia. M. 

 Schonbein has remarked that the quantity of nitrate of ammonia 

 condensed with the vapor of the water is very variable, sometimes 

 almost m7, and he is disposed, in the absence of any positive deter- 

 mination, to attribute these variations to changes of temperature. 

 It is not, however, necessary that the water should boil, as the salt is 

 produced during all evaporation, and its presence may be shown in 

 the water that remains after a portion has been evaporated. A sheet 

 of filtering paper dipped in pure water, and dried in the air, becomes 

 impregnated with sufficient nitrate of ammonia to be distinguished in 

 the water with which the paper is washed, and it can be discovered 

 in linen that has been washed and hung up to dry. In all these 

 cases the production of nitric acid may be rendered more evident by 

 adding to the water which is evaporated a little potash, to fix the 

 acid. Wet sand dried in the air becomes impregnated with nitrate 

 of ammonia. 



ACTION OF NITROGEN AND NITRIFICATION. 



This interesting subject has been brought before the Academy of 

 Sciences, Paris, by Mr. Sterry Hunt, in a note read at a recent meet- 

 ing. He attributes the simultaneous production of an acid of nitro- 

 gen and ozone, whether by the electric spark, or by the slow oxida- 

 tion of phosphorus, to the power which oxygen possesses of burning 

 ammonia, thus setting at liberty the acid of a small quantity of nitrate 

 of regenerated ammonia, and even, according to the observations of 

 M. Houzeau, carrying its oxidizing action so far as to acidify the 

 nitrogen of the atom of ammonia. Thus, as some chemists have 

 maintained, certain reactions attributed to ozone are due to a small 

 quantity of nitrous acid, which is formed when the active oxygen is 

 formed, while the active oxygen is in contact with the moist atmos- 

 pheric nitrogen. On the other hand, the hydrogen set at liberty by 

 certain reagents would have the eifect of destroying the nitrous acid 

 of the nitrate of regenerated ammonia, thus setting at liberty the 

 ammonia of the salt, and forming a second atom of ammonia, in con- 

 sequence of the reduction of the acid. Mr. Hunt asserts that the 

 experiments of Professor Schonbein confirm his theory in a remark- 

 able manner. He adds that Professor Schasffer, of Washington, 

 twelve years ago, in a memoir on the means of recognizing the 



