368 Observations on a Hurricane in Ohio. 
necessary is merely a disk of bismuth as large as a shilling, soldered 
to a corresponding one of copper, blackened, and erected in the 
focus of the reflector, while conductors pass from each disk to the 
poles of the galvanometer. With this arrangement the heat of a 
non-luminous ball at the distance of 12 feet will impel the needle 
near 180°, and if the connexions and reversals are properly made 
will keep it in a continued revolution. 
I have thus given you a brief sketch of an instrument which 
seems to supply a desideratum on the lecture-table, when the com- 
mon thermometer is too small to afford to a class that direct and 
full satisfaction which, in a subject so important as that of heat, is 
very desirable to every professor. I have not so far attempted to 
use it extensively as an instrument of research, yet it shows evi- 
dently the importance of massiveness in conductors for feeble cur- 
rents, such as those produced by thermo-combinations ; nor am I 
certain that I have arrived at a maximum in this particular, for so 
far as I have proceeded in using thicker conductors for the coil, 
the deflecting effects have been increased. 
~ Tam, &c. Joun Locke. 
London, Aug. 30, 1837. 
Arr. XXI.— Observations on a Hurricane which passed over Stow, 
in Ohio, October 20th, 1837; by Extas Loomis, Professor of 
Mathematics and Nat. Philosophy in Western Reserve College. 
On the morning of October 20th, 1837, a hurricane, of destruc- 
tive violence, passed over Stow, in Ohio. This town is situated 
about thirty miles south of Cleveland, in north latitude 41° 12’, and 
west longitude 81° 25’. As the hurricane occurred during the dark- 
ness of the night, we can collect little information respecting it, with 
the exception of the record which the wind has itself left of its pro- 
gress. During the night of the 19th and morning of the 20th of 
October, there was a thunder shower at Stow, which extended into 
some of the adjoining towns. The lightning was rather vivid, the 
rain fell in torrents, and the wind blew fresh during most of the night. 
About three o’clock in the morning, a whirlwind formed near the 
center of Stow. It moved rapidly from west to east, over an extent 
of about three miles, its breadth varying from forty to sixty, and oc- 
casionally to eighty rods. For about a mile of its course, few objects 
