V. Experiments with pressure on excitable tissues

The effects of temperature on excitable tissues have been well worked out; but, so far as I have been able to ascertain, no physiologist has tried the effects of pressure. From physical analogies it appeared to me probable that increase of pressure would act on excitable tissues in a manner analogous to decrease of temperature, and conversely; but the results of my experiments have not borne out this anticipation. Nevertheless, the research seems worth publishing. In a small glass chamber, made for the purpose, I was able to place the freshly excised heart of a frog or a tortoise, and there to submit the rhythmically beating tissue to any increase of atmospheric pressure that I desired, up to a maximum limit of twenty-two atmospheres, beyond which it was not safe to go with the glass chamber that I had.