248 CHANGE OF LEVEL IN THE 



waters, to which my attention has been drawn. It is 

 the result of long observation that the surface of this, 

 and, I believe, of the other lakes also, is subject to gra- 

 dual, and, as some believe, periodical, but certainly very 

 considerable alterations of level. 



This is proved by the observations of those who reside 

 on their shores. The water on sand-banks becomes 

 shallower or deeper. Mills at the mouths of streams are 

 rendered permanently useless by the rising level of the 

 lake into which the streams descend. Former roads 

 along the lake, as that immediately beyond Buffalo, have 

 been overflowed, and rendered impassable. Old beaches, 

 covered with trees and cliffs, are seen far inland, showing 

 the greater height to which the waters formerly attained; 

 while others, which men remember to have been at a 

 distance from the lake, have again been reached, and 

 are in progress of being undermined. 



The height and periods of this rise and fall are both 

 uncertain. In 1838, Lake Erie reached the highest 

 elevation it has attained during the present century, and 

 since that time it has been gradually receding. In 

 1788 or 1790, it was higher than in 1838, after which 

 time it receded probably for many years, and then 

 began again to rise. On the shores of Michigan, the 

 rise was estimated at 5j feet between 1819 and 1838 ; 

 and in another place, a resident of twenty-three years 

 on the spot observed that, though it was highest in 

 1838, it was, in 1840, still 4 feet higher than when he 

 settled there in 1817. 



Facts of this kind have long drawn the attention of 

 the inhabitants along the lakes. They are to them a 

 source of anxiety, and, where low flat lands stretch 

 along either shore of the lake, of alternate gain and loss. 

 They are also interesting to the geologist, in connection 

 with the ancient terraces, and the frequent more or less 

 distant sea-beaches which skirt the lake-shores at 



