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 
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. © notes contained exact 
mention of hours, at which the elevation or ——- was 
manibes and the state and variation of the have 
never ceased to regret that it was not in my onaee to exam- 
ine aa collate them. 
The positions of Michilimackinac and Fort Dearborn, 
render them less subject to the circumstances just me 
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. Ido not ——s re- 
member the result of the trial made at either plac ey 
aiechanad those made elsewhere, but, if my conilieaeiat 
serves me, the fact was less distinct] 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 
pein gach the inquiry of him, and beg that he communicate 
with you 
Letter from ied. Joseph Lovell, Surgeon General in the 
rmy of the United States, 
Msi 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 journ 
of Capt. Whiting of the army. Several others have noticed 
the same thing at Fort Howard, though they have differed, 
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 
I have conversed is, that the change is produced by 
the winds acting on the waters of Lakes Michigan and Hu- 
~~ 
