132 The Ottawa Naturalist. [Oct. 



THE NITROGEN COMPOUNDS IN RAIN AND SNOW. 



It may be remembered that one of our addresses at the 

 opening meeting of last winter's lecture course was on "Rain 

 and Snow," the lecturer, Mr. Frank T. Shutt, Chemist of the Ex- 

 perimental Farms, outlining their influence iipon the industries, 

 the agriculture and the health of the world. 



Perhaps the most interesting part of the paper from the 

 strictly Canadian point of view was the presentation of certain 

 data concerning the nitrogen content of snow — the first of the 

 kind, so far as was known, obtained in the Dominion. The 

 fertilizing value of the "blanket of white " was clearly shown, the 

 1,000 tons (approximately) of snow per acre which falls dtiring 

 the winter at Ottawa containing a considerable amount of this 

 all important element of plant food — nitrogen — in readily 

 assimilable forms. 



For some time past every fall of snow and rain has been 

 analysed at the Chemical Laboratory of the Central Experi- 

 mental Farm, Ottawa, and in the forth-coming report of that 

 institution further interesting data on this subject will appear. 

 From these results we have been permitted to make the following 

 summary : 



For the year ending February 29th. 1908, there fell 24.05 

 inches of rain and 133. inches of snow, making a total precipitation 

 of 37.35 inches — 10 inches of snow being reckoned as the equival- 

 ent of 1 inch of rain. The total amount of nitrogen in this pre- 

 cipitation amounted to 4.323 lbs. per acre, and of this approxi- 

 matel}^ 75% or 3.243 lbs. was present in the rain, and 25% or 

 1.080 lbs. in the snow. We further learn that the solvent action 

 of rain is much greater than that of snow, i.e. that rain is much 

 richer, weight for weight, in nitrogen compounds, than snow. 

 Rain, therefore, is the better or more thorough cleansing agent 

 of the atmosphere as regards the ammonia and other gases 

 present that contain nitrogen compounds. Another point brought 

 out by this work is that the first portion of the rain or snowfall 

 is richer than that which falls subsequently and that the period 

 elapsing between the falls has a marked effect on the composition. 



Data of a similar character have been obtained in many 

 European and other countries and this work is therefore both 

 useful and interesting for the purpose of comparison. It may be 

 cited as an illustration of one of the many valuable researches 

 undertaken by the Experimental Farm system. 



