Note c — BOOK I.

July 8. 1707, (called for some time after the Hot Tuesday,) was so excessively hot and suffocating, by reason there was no Wind stirring, that divers Persons died, or were in great Danger of Death, in their Harvest-Work. Particularly one who had formerly been my Servant, a healthy, lusty, young Man, was killed by the Heat: And several Horses on the Road dropped down and died the same Day.

In the foregoing Notes, having Notice of some Things relating to Heat, although it be somewhat out of the way, I hope the Reader will excuse me, if I entertain him with some Observations I made about the Heat of the Air under the Line, compared with the Heat of our Bodies. J. Patrick, who, as he is very accurate in making Barometrical and Thermometrical Instruments, had the Curiosity for the nicer adjusting his Thermometers, to send two abroad under the Care of two very sensible, ingenious Men; one to the Northern Lat. of 81; the other to the Parts under the Æquinoctial: In these two different Climates, the Places were marked where the Spirits stood at the severest Cold and greatest Heat. And according to these Observations he graduates his Thermometers. With his Standard I compared my Standard Thermometer, from all the Degrees of Cold, I could make with Sal Armoniack, &c. to the greatest Degrees of Heat our Thermometers would reach to. And with the same Thermometer (of mine) I experimented the greatest Heat of my Body, in July 1709. First in an hot Day without Exercise, by patting the Ball of my Thermometer under my Armpits, and other hottest Parts of my Body. By which means the Spirits were raised 284 Tenths of an Inch above the Ball. After that, in a much hotter Day, and indeed nearly as hot as any Day with us, and after I had heated my self with strong Exercise too, as much as I could well bear, I again tried the same Experiment, but could not get the Spirits above 288 Tenths; which I thought an inconsiderable Difference, for so seemingly a very different Heat of my Body. But from some Experiments I have made (altho’ I have unfortunately forgotten them) in very cold Weather, I imagine the Heat of an healthy Body to be always much the same in the warmest Parts thereof, both in Summer and Winter. Now between those very Degrees of 284 and 288, the Point of the equatorial Heat falleth. From which Observation it appears, that there is pretty nearly an equal Contemperament of the Warmth of our Bodies, to that of the hottest Part of the Atmosphere inhabited by us.

If the Proportion of the Degrees of Heat be desired from the Freezing-Point, to the Winter, Spring, and Summer Air, the Heat of Man’s Body, of heated Water, melted Metals, and so to actual Fire; an Account may be met with of it, by my most ingenious Friend, the great Sir Isaac Newton, in Phil. Transact. Nᵒ. 270.