THE OTTAWA NATURALIST 



VOL. XXI. OTTAWA, DECEMBER, 1907 No. 9 



RAIN AND SNOW.* 



By Frank T. Shutt, M.A., 



Chemist, Dominion Experimental Farms. 



The speaker, at the outset, said that if the title upon the 

 programme had led his hearers to imagine that his'remarks were 

 to be upon the weather, they were mistaken. There were 

 weather-wise people, ofificial and unofficial the former con- 

 stituted the staff of the Dominion Meteorological Service, the 

 latter, the rest of the population. Weather prediction, according 

 to the best authorities, mtxst be based on data of temperatures, 

 pressures, etc., taken over wide areas and such data can only 

 be obtained through the recognized, official channels. Again, 

 safe predictions can only be made for a period of 48 hours ahead. 

 Of course, some people may possess the gift of prophecy; one 

 cannot deny it, but judging from results as regards weather, 

 one is forced to the conclusion that the days when the spirit 

 of the lying prophet entered into man are not passed. 



Considering rain and snow from the utilitarian point of view, 

 the lecturer said it was his desire to offer one or two thoughts on 

 the role of these elements? in the economy of Nature, their 

 influence upon the industries, the agriculture and the health 

 of the world. 



The first fact to be pointed out and it is one of funda- 

 mental importance was that there was a constant circulation 

 (though that word scarcely describes the process) of the moisture, 

 the water of the world. Continuously, by day and by night, 

 summer and winter, there ascends from sea and lake and river 

 and moist land aqueous vapour. This evaporation is, of course, 

 due to the heat of the stm, though direct sunlight is not necessarv 

 for the operation. Water gives oft' vapour at all temperatures 

 and there is the direct conversion of snow and ice into vapour. 



* This is a condensed report of an address delivered before the 

 Ottawa Field Naturalists' Club in the Normal School, Ottawa, Dec. 

 10th, 1907. Ed. 



