L'l 



FLUCTUATIONS OF LEVEL 



Table showing the Gkeatest Change of Surface within a :\[untii aiusinci from the 



Effect of Winds. 



Tliei-e arc at cacli of these places momentary floods and subsidencies that exceed 

 the recorded range of the surface, of which memoranda arc made, and which I have 

 already given. 



In water tables, the object of which is to ascertain an average level for each month 

 and for each year, sudden movements are avoided as much as possible. They arc 

 noted in the column of remarks, but do not enter the general average. 



The table of extreme fluctuations just given represents, therefore, more properly 

 the effect of such winds or storms as prevailed for some hours or days in one 

 direction, rather than the result of sudden gusts producing impulses that pass away 

 as suddenly. 



The monthly range is far greater at Buftalo than at Cleveland, for reasons 

 already given. 



At Oswego it is less than at any place on Lake Erie, owing, probably, to a greater 

 depth of water, especially near the shore. 



For tlie port of Cleveland, Ohio, in twenty-one cas(-s of high water— the wind 

 was northeasterly, eight; northwest, three; south, three; and the remainder calm. 

 At Buffalo, in six cases out of nine, it occurred under the influence of a southwest 

 or down l>akc breeze; and in the same number of instances of lowest water, the 

 wind was from the east, or up the Lake, six times. 



At Oswego the effect of winds is equally apparent, but the amount of fluctuation 

 produced is less. Li twenty-one cases — the highest water happened with a west 

 wind, fifteen times; northwest, once; southwest, once; and south (or off shore), 



