"292 A liecent Visit to Lake Itasca — Uj^ham. 



original map, appearing as a bay connected with Itasca by a narrow 

 strait. During recent years tlie level of Itiisca has fluctuated only 

 a few inches, varying from thirteen to eight inches below Elk 

 lake; but fifty-three years ago, when Nicollet was tbere, his map 

 indicates that lake Itasca stood at least two or three feet higher 

 than now, being raised so high that Elk lake became a part of 

 Itasca. The method of Nicollet's exploration of Itasca was prob- 

 ably by a canoe trip around its entire shore, for he mapped every 

 noteworthy tributary; and therefore his testimony of the relation- 

 ship of these lakes in 1836 seems decisive. This date was only ten 

 years after the highest known flood of the Red river, when its 

 water rose five feet above the surface where Winnipeg is now 

 built; and it was two years before the highest known stage of the 

 great Laurentian lakes in 1838, when lake Erie stood six feet 

 above its lowest recorded level, which was in the winter of 1819- 

 20. It is also interesting to note in comparison with these high 

 stages of the Red river, Itasca and the Laurentian lakes, that 

 Devil's lake, in North Dakota, which has no outlet, shows evidences 

 of having attained, about the year 1830, a level eighteen feet 

 higher than now, reaching then to the line that limits the large 

 and dense timber of its bordering groves. Below that line are 

 only smaller and scattered trees, of which Captain E. E. Heerman 

 informs me that the largest found by him had fifty -seven rings of 

 annual growth. Within the twenty-two years since the building 

 of Fort Totten, Devil's lake has fallen nine or ten feet; and it has 

 fluctuated five feet under the influence of the changes in the 

 -average annual precipitation of rain and snow during the past ten 

 years. Itasca, affected by similar changes in the average rainfall 

 and snowfall, but having an outlet, has varied in level not more 

 than six or eight inches since 1880. 



October 8, 1889. 



