148 
MR. J. F. MILLER ON THE DEW-POINT. 
rain ; but the gauge was constantly under cover, and consequently but little exposed 
to the direct rays of tlie sun, which will account for the great difference between the 
results at Whitehaven and the metropolis. Had the gauges been in all respects 
similarly circumstanced, the evaporation at London, from its higher mean temperature, 
would probably have been found to exceed the amount registered in the higher lati- 
tude. 
The Observatory, Whitehaven, 
October 2Qth, 1849. 
