321 
Report on the Observations recorded during the Years 1837, 
1838, 1839, and 1840, by the Self-registering Anemometer 
erected at the Philosophical Institution, Birmingham. By 
A. Fotuert Osver, Esq. 
Tue records of the Self-registering Anemometer, erected at the 
Philosophical Institution at Birmingham, are now tabulated for 
a period of upwards of four years; and though the observa- 
tions from a single station can neither possess the interest nor 
value of those we may hope to derive at no distant period from 
several, yet so little is at present known respecting the laws of 
the aerial currents in this latitude, that I have ventured to bring 
forward the few facts at present collected. 
The plan adopted first suggested itself in consequence of my 
friend Mr. Snow Harris having requested me to take out the 
mean hourly force of the wind without reference to its direction, 
which he apprehended might show some connection between 
the wind’s movements and the horary oscillations of the baro- 
meter*. Considering that this mode of examining the anemo- 
metrical records might exhibit other results equally deserving 
investigation, I pursued the inquiry in the manner set forth in 
this paper. 
The observations are comprised in the years 1837, 1838, 
1839, and 1840. The usual plan is adopted of regarding De- 
cember, January and February as the winter quarter ; March, 
April and May the spring; June, July and August the sum- 
mer; and September, October and November the autumn. 
Having procured a number of sheets of paper, ruled simi- 
larly to Table I., I commence with December 1, 1836, and 
note down the mean force and direction of the wind during 
each hour of the day, as recorded by the anemometer. The 
figures express, in pounds avoirdupois, the force exerted by the 
wind on a surface of one foot square, kept at right angles to 
the current. I have not noticed the force when less than half a 
pound is registered, it being difficult to read off a smaller 
amount with accuracy ; and in heavy gales it is not possible to 
ascertain the mean force of the wind even so nearly as this. 
Owing to the oscillations of the vane, it is sometimes difficult to 
ascertain precisely the mean direction; besides which, the 
instrument occasionally indicates an intermediate place between 
* Second Report of the British Association, p. 233. 
1840. Y 
