zjb Observations on

it a very fair trial, and can assert, that Inever found air to be at all sensibly injuredin those circumstances, but rather, if Icould depend upon my application of thetest of nitrous air for so small a difference,it was something better than the externalair. I have sat an hour with my arm in atrough of very warm water, and my warmhand in a glass jar placed with its mouthin the water (my hand, of course, per-spiring, though insensibly, all that time)but when I examined the air within thejar immediately afterwards, it appeared notto have been the least injured by theprocess.

But what I expected to produce a muchmore sensible change in the air was theperspiration under the arm pits, after walk-ing, or using much exercise. For thispurpose, I have sometimes introduced phi-als of warm water, and poured it out, whenI had introduced my hand as carefully aspossible into the place; but at other timesI have put open phials, with perforationsin the bottoms, and also open glass tubes,

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