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The mean Heat of the fhaded Air, in Spring, 
Summer, Autumn, and Winter, taken from the 
mean nocturnal Heat, and from the mean Heat at 
2 or 3 p. m. is 6i, 78, 71, and 52 Degrees. 
The mean Heat of the fhaded Air at 2 or 3 p. m. 
in Spring, Summer, Autumn, and Winter, is 65, 
82, 7 5, 55 Degrees 5 and the mean no&urnal Heat 
in thefe Seafons is 57, 74, <58, and 49 Degrees. 
Therefore our Winter's nofturnal Hear, at a Me- 
dium, coincides nearly with the temperate Heat in 
England. 
The Thermometer, when fufpended five Feet 
from the Ground, and expofed to the diredl Rays 
of the Sun, and to thofe refle&ed from our fandy 
Streets, has frequently rofe in a few Minutes, from 
15 to 26 Degrees, above what was at that time the 
Heat of the fhaded Air (but I have never yet made 
that Experiment when the Heat of the fhaded Air 
was above 8 8) : When we are therefore expofed in 
the Streets to the Sun in Summer, we infpire Air 
from 4 to 28 Degrees warmer than the Heat of the 
human Body. 
The Thermometer, when buried in the Sands of 
the Streets, when the Heat of the fhaded Air wa 
88, rofe in y Minutes to 108, tho' there was at the 
fame time a moderate Wind. 
In Jane 1738, when the Heat of the fhaded Air 
was 98, the Thermometer funk one Degree in my 
Arm-pits 5 but continued at 98 in my Hand and 
Mouth: From which we fee what little Concern 
the Air has in cooling the Blood in the Lungs. 
Two Men who were then in the Streets (when the 
. + Heat 
