An Account of a Dog dissected,
By Mr. HOOK.
IN Prosecution of some Inquiries into the Nature of Respiration in several Animals; a Dog was dissected, and by means of a Pair of Bellows, and a certain Pipe thrust into the Wind-pipe of the Creature, the Heart continued beating for a very long while after all the Thorox and Belly had been open'd, nay after the Diaphragm had been in great Part cut away, and the Pericardium remov'd from the Heart. And from several Trials made, it seem'd very probable, that this Motion might have been continued, as long almost as there was any Blood left within the Vessels of the Dog; for the Motion of the Heart seem'd very little chang'd, after above an Hours time from the first displaying the Thorax, though we found, that upon removing the Bellows, the Lungs would presently grow flaccid, and the Heart begin to have convulsive Motions; but upon removing the Motion of the Bellows, the Heart recovered its former Motion, and the Convulsions ceased. Though I made a Ligature upon all the great Vessels that went into the lower Parts of its Body, I could not find any Alteration in the Pulse of the Heart; the Circulation, it seems, being perform'd some other Way. I could not perceive any thing distinctly, whether the Air did unite and mix with the Blood; nor did in the least perceive the Heart to swell upon the Extension of the Lungs; nor did the Lungs seem to swell upon the Contraction of the Heart.
