220 
But, then, in these seasons the range is, for the most part, steady, 
varying but little ; while it is the sudden rise or fall of the range, 
when the day temperature is suddenly raised much above what it 
had been a short time before—the night temperature remaining 
the same, or, perhaps, falling lower—of which persons are ordinarily 
most sensitive. And this irregularity will be found also in both 
Tables, to occur in the spring. The cause, no doubt, is the pre- 
valence of easterly winds, accompanied by a very dry state of the 
air, at that season, rendering the nights very cold, notwithstanding 
the great power of the sun during the day, to heat the lower strata of 
the atmosphere. Hence it is that the spring season is so trying, 
not merely to certain classes of invalids, but sometimes even to 
healthy people. Bath certainly does not afford entire exemption 
from this evil ; but it will be shown further on that, whatever may 
be its increased mean daily range of temperature in spring, to give 
it any disadvantage, there is a still greater increase of the same, 
and, in consequence, a greater disadvantage, in several other towns 
shortly to be compared with it. 
Next in importance to ascertaining the mean daily range of 
temperature, is the determination of the temperature of the several 
seasons at Bath, set down for each of ten years in the Table 
on the following page 
tae ee 
