Meteorological Observations at Hudson, Ohio. 313 
barometer in latitude ants H’ the ipso corres} 
itude 45°. bs “ 
apa ~ . = - 28.806. New. York, - 30.086 
-. «=. +.007  Cor’n for temperature, —.108 
a Sean 1131 feet, +1. 231 Reduce. for 10 feet,  +.011 
Correction for gravity, —.010 Correction for gravity, —.012 
— 30.034 29.977 
Montreal, - - 29.886 Quebec, - -. 29.543 
Reduc. for 91 feet, “+.102 Reduce. for 330 feet,  +.371 
Correetion for gravity, +. 001 Correction for gravity, +. 005 
i 29.989 29.919 
In ne transactions of the Albany Institute, vol. ii, p. 156, the 
zero error of the Quebec barometer is stated at ++-0.110 com- 
pared with that at Montreal. It is presumed that this correc- 
tion. has been tab pes above mean result, The eleva- 
rence. fi is not ste ‘tow testes exceeds the mean level of 
the sea, but probably not. much, as the tide is said to rise at 
Quebec. As it is now clearly proved that the mean pressure of 
the atmosphere at the level of the sea is mot every where the 
same, a most extensive field of inquiry is presented to 
experimentally the law of its variation. In particular, it is desir- 
able to know, whether over an elevated continent the pressure is 
the same as at the same height over the sea in the same latitude. 
In order, however, that observations may be of any value for this 
purpose, they s should embrace a period of several years, the zero 
ertor of the instrument should be accurately determined, and 
also the. elevation spare the level of the sea. 
“The llowing table exhibits the instances ,corrected for tempera- 
ture, in which the barometer has 1 risen above 29.25. Although the 
barometer may have remained at this height during the period of 
Several successive observations, it is regarded as but one instance. 
1839, Feb. 18, 3 e.m.[29.26 
March 
pon ding to lat- 
= xb, fay on aa. 
