(nen 
in the Night and in Winter. 105 
dithoagi not exactly in point, observation not being season- 
ably made. The wheel was a tub wheel; it was in the winter 
season subsequent to a thaw which had cleared the stream 
of ice; the wind for some time previous had blown very hard 
from the northwest, which at-that place was opposite the 
course of the stream, (which was small, barely sufficient for 
a grist mill,) but had now subsided. The mill was started as 
usual, in the morning; after raping an hour or more, it 
was observed to slacken; the gate was raised, but soon 
the wheel went slower than before ; more water was let 
on, but with little effect: examination was then made for 
the cause, when it was found that the water was become 
thick with frost, having a large portion formed into crys- 
tals, in some measure resembling snow and water. It 
became so thick in a few minutes. that it had not suflicient 
fluidity to turn the wheel at all, and almost ceased to flow 
in the stream which had in consequence risen considera- 
bly. his was about 9 o’clock A. M. ; between 10 and 
11 the stream became clear, the frost having lsappented. 
It was probably occasioned, in part at east, old 
wind blowing with so much force against the bee. and 
mixing with the water that the whole stream was reduced 
to the freezing temperatate and congelation pened 
every part equally. 
robably you will have communications from persons 
hk have made observations more recently apd with more 
attention. Should any thing, however, related above be 
considered of use, you are at liberty to dispose of this letter 
as you may think proper,—being always willing, however 
eebly, to contribute whatever is in my power to the ad- 
vancement of science. 
2. Extract of an anonymovs letter io the Editor.* 
author remarks respecting the supposed accele- 
The 
‘ration of water-wheels working during the night and in 
winter: “ This fact is well known to most persons, who 
have been connected with mills, and I remember many 
years ago, being asked to give an explanation of the cause. 
* Post marked Beauvort, S. Carolina, October 12, 1824. 
Ver. IX.—No. 1. 14 
