SUMMAUY. 



vapour in a cubic foot of air, was 3*69 grains, and the mean 

 additional weight required to saturate a cubic foot of air, 0*67 

 grain. The mean degree of humidity (complete saturation 

 = 1,) was 0-852. 



The mean amount of vapour mixed with the air would have 

 produced water, if all had been -precipitated at the same time 

 on the surface of the earth to the depth 4i'4>S in. The mean 

 weight of a cubic foot of air, under the mean pressure, tempe- 

 rature, and humidity, was 538*5 grains. 



The force and direction of the wind, being from esti- 

 mation, can only be considered as rough approximations. The 

 Anemometer now being constructed by Mr. Osier, wiU, I trust, 

 in future years, furnish valuable and interesting information 

 in this department. 



JOHN HARTNUP. 



LlYEBPOOL ObSEBVATORY, 



1851, January 25th. 



173 



