88 On the supposed Tides in the 



inference of an inward current. I glanced at them, at the 

 time, merely from a desire to explore all causes that- might 

 be at hand. The first suggested itself from finding, as I 

 slowly coasted the southern shore of Green Bay, a breeze to 

 arise, with great regularity, at a certain hour of the morning, 

 and blow gently from the land. My notes contained exact 

 mention of hours, at which the elevation or depression was 

 manifest, and the state and variation of the wind. I have 

 never ceased to regret that it was not in my power to exam- 

 ine and collate them. 



The positions of Michilimackinac and Fort- Dearborn, 

 render them less subject to the circumstances just mentioned. 

 A small and sluggish stream empties itself at the latter, but 

 I made the experiment at a distance from the mouth of it, 

 upon the margin of the broad lake. I do not precisely re- 

 member the result of the trial made at either place. They 

 corroborated those made elsewhere, but, if my recollection 

 serves me, the fact was less distinctly marked. 



You refer to Charlevoix and La Hontan. I think the ex- 

 istence of such a tide is referred to by Fra. Marguette in 1673. 



It has suggested itself to me while writing, that some of 

 the medical officers, stationed upon the north western fron- 

 tier, may have made observations upon this phenomenon, 

 and communicated them, with other scientific matter to the 

 head of their Department, our medical friend Lovell. I will 

 make the inquiry of him, and beg that he communicate 

 with you. 



Letter from Doct. Joseph Lovell, Surgeon General in tlie 

 Army of the United States. 



Washington, April 2d, 1827. 



My dear Sir — At the request of Mr. Storrow, I enclose 

 you the only document I can find relative to the supposed 

 tides in the upper lakes. It is an extract from a journal 

 of Capt. Whiting of the army. Several others have noticed 

 the same thing at Fort Howard, though they have diflfered, 

 both as to the height of the rise, and its frequency. Capt. 

 Smith informs me that while he was there the variation never 

 exceeded six inches. I cannot learn that it has been ob- 

 served at any other place. The general belief of those with 

 whom I have conversed is, that the change is produced by 

 the winds acting on the waters of Lakes Michigan and Hu- 



