316 Meteorological Observations at Hudson, Ohio. 
mean temperature of the place, yet with the assistance of the 
hourly observations made at Philadelphia by Capt. Mordécai; we 
may be able to determine it pretty satisfactorily. The diurnal 
oscillation from 9 A. M. to 3 P. M. is nearly the same at both 
places ; we may then without much fear of error, assume that the 
excess of the 9 A. M. observations above the mean temperature is 
also the same, viz. one degree. Subtract then one degree from 
A8°.6, and also 0°.2 for the zero error of the thermometer, we 
have 47°, 4 for the mean temperature of Hudson. 
‘The same problem I have attempted to solve by means of the 
temperature of wells. There are two deep wells in this vicinity 
whose temperature I have Seg oid tried. The following are 
the ebservatians.- 
ee A. B. 
; Date. Depth to surf,  Feiapetate, hiets* - a. Temperature, | 
Neen oubsiiais as feet. degrees. 
“1838. Mareh 87,64} 49.8 46° | 48.4 
June 6,) 53 501 | 46 | 489 
August 4,) 54 _ 50.4 46 49.9 
Sept, 20,| 64 50.4 AT 49.7 
33}. BB 50.3, 49.1 
1839. Jan. 5, 49.4 A7 47.5 
Feb. 13,|. 54. “|, 498 |. 47. 46.4, 
|Mean of Ist yrs.obs.. 53.7 | 50.0 | 464 | 486 _ 
It will be perceived ‘that the temperature varies very little with 
the season. Observations were therefore subsequently made 
— twice a year, about the time: of maximum and minimum. 
$$$ 
bese , Diget ts surf. ma aperstare, ar, | Devt sa Tenpenaes 
AT —T68 
47.5 49.1 
47.5 50.0 — 
46.5 48.7 
47.0 49.3 
t 1.47.0. |, 490 
oof ‘observations present wibhsend remarkable circumstances. 
One-is, that the mean temperature of the well A should be for 
 eeanonnctly 2.4 higher than B pyet oo are only t poe? 
