s^8 Dr. Hunter’s Obfervations on the Heat 
the heat of deep caves, or wells in the fame climate. If fur- 
ther experience and obfervation fhould confirm the above opi- 
nions, it will be attended with this advantage, that we fhall 
be pofleflfed of an eafy and ready method of afeertaining the 
mean temperature of any climate ; which, with a few obferva- 
tions of the extremes of heat and cold at particular fea- 
fons, will teach us as much of the country, with regard to 
heat and cold, as the meteorological obfervations of feveral 
years. 
For obtaining the temperature of the earth the befl obfer- 
vations are probably to be collected from wells of a confidera- 
ble depth, and in which there is not much water. Springs 
iffuing from the earth, although indicating the temperature of 
the ground from whence they proceed, are not fo much to be 
depended upon as wells ; for the courfe of the fpring may be 
derived from high grounds in the neighbourhood, and it will 
thence be colder ; it may run fo near the furface as to be liable 
to variations of heat and cold from fummer and winter; or it 
may be expofed to local caufes of heat in the bowels of the 
earth. Wells feem alfo better than deep caverns, for the 
apertures to fuch are often large, and may admit enough of the 
external air to occasion fome change in their temperature. 
Wells are not, however, to be met with in all places, and in 
that cafe We muff remain fatisfied with the temperature of the 
fprings. 
The following obfervations were made in the Ifland of Ja- 
maica, where there are flat lands in many parts towards the 
coafl, but all the interior part of the country is mountainous. 
The heat is greateft in the low lands, and decreafes as you 
afeend the mountains. The town of Kingfton is fupplied with 
water from wells. The ground on which it flands rifes with 
a gentle 
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