320 Meteorological Observations at Hudson, Ohio. 
arbitrary scale, explained in this Journal, vol. xxxvi, p. 173, may 
possess some interest. The mean of the extreme excursions of 
the vane during an interval of five minutes, I call its true ditec- 
tion; and the force I regard as the distance. This is resolved 
in the direction of the four cardinal points by the usual method. 
Each observation is resolved separately, and the sum of the north- 
ings and southings, eastings and westings, for a month, furnishes 
its mean direction. The following table exhibits the sum of 
these quantities for the corresponding months of the three years. 
Course. 
~t 
_ 
1.2) 
_ 
ee Bei 
SABAY RRB 
eSaBsso8Sess 
N. s. . “ars we Course. ve 
. Sum of 9 a.m. and 3 Pym. | 1297.50 | 1088.07 | 642.53 | 2387.97 | s. 83° ws” 
It appears then that during a period of three years, the pro- 
gress of the wind in spring ‘and summer has been at 9 A. M. 
from north to south, in autumn and winter from south to 
the latter motion being slightly i in excess so as to produce & Te 
sulting motion from the south. At 3 P.M. the wind’s progress 
has been from the north during nine months of the year, and 
this excess of northerly winds has been’ such, that taking the 
sum of observations at both hours, the absolute progress — 
beén from a point seven degrees north of west. Dividing this 
absolute progress from north to south by the whole number of 
observations, we obtain .0991 for the mean motion in this 
tion corresponding to each observation, The mean force of the 
wind has been 2.04, making the actual progress of the wind 
from north to south about five per cent. of the total motion; 
if we assume with Mr. Redfield (Am. Jour. ‘vol. xxv, Pp 125) 
the average velocity of the wind at eighteen miles an hour, W° 
ca, the following important conclusion, that at this place 
the absolute progress of the wind, in the direction of the mer 
Ae 5 orally nami ate of seven eighths of a mile 
