1896.] PARKER — CLIMATOLOGY OF ROCHESTER. 223 



summer is 67°, at Omaha it is 74" ; for the autumn it is 56", at 

 Omaha it is 52° ; for the winter it is 27°, at Omaha it is 24°. 



As showing the mildness and lack of change at some places it 

 may be stated in this connection that the spring averages 60" at Los 

 Angeles, the summer 70", the autumn 65°, and the winter 55° ; 

 and as a marked example of severity of temperature and temperature 

 changes St. Vincent with spring 35°, summer 63", autumn 38°, 

 winter zero. And so we might go on citing figures to show that 

 Rochester comes in with severity in no direction as compared with other 

 places, with summers that are cool, but not cold, and winters that are 

 cold without severity. It may be of interest to look somewhat into 

 the causes that govern these conditions. The modifying influence 

 is found in Lake Ontario, principally, which takes in the heat of the 

 sun in summer and gives it out again in winter, thus serving as a 

 balance to keep conditions moving at all times in a groove not so far 

 removed from the normal. 



Heat Storage of Lake Ontario. 



Lake Ontario is said to contain about 636 cubic miles of water, 

 and the following calculation is based on this quantity. It is doubt- 

 ful whether it can serve any useful purpose beyond exhibiting the 

 massive grandeur of some of the forces in nature, for the figures are 

 of such huge dimensions it is difiicult to convey any definite idea of 

 their magnitude. Let it be supposed that this body of water is reduced 

 in temperature throughout 5^* (the change may be much greater) and 

 we find by calculation that the cooling of the waters would give forth 

 as much heat as the burning of about 2,500,000,000 tons of coal ; or 

 about five times the quantity mined yearly in the world. This heat, 

 of course, is taken from the amount received from the sun during 

 the summer and part of the spring and fall, and given out again 

 during the cold season, when it is most needed. 



For all the lakes the quantity of heat given of^ during the cold 

 season probably exceeds that which would be derived from the burn- 

 ing of over 30,000,000,000 tons of coal. These aggregates, large as 

 they are, are not suflicient, however, to entirely reverse the vast 

 influence operating to produce heat and cold over this portion of the 

 earth's surface. The provision is simply enough to prevent extremes 

 of heat in summer and greater severity of cold in winter. As an 

 example of this modifying influence, attention may be called to Omaha, 

 with highest temperature of 105° and lowest of -32°, against 99° and 



