to whom we are beholden for a compleat Display of the Mechanical Structure of the Heart , and a most ingenious Rationale of its Action. Yet there remain several Doubts and Difficulties about it (in my Opinion) not sufficiently accounted for; towards the resolving some of which, I shall offer what my own Thoughts have suggested to me, and leave it to the Consideration of the Reader.
The Learned Dr. Lower (whose accurate Piece on this Argument will insure his Reputation so long as Physical Knowledge shall last in esteem) has so well accounted for the Systole, or Contraction of the Heart, from the Mechanical Structure of it, that he seems almost to have exhausted the Subject; and had
he been as happy in discovering the true cause of the Diastole, he had left little room for the Industry and Sagacity of others about this Viscus.
But having judiciously and solidly explain'd the Systole, he contents himself to ascribe the Diastole to a motion of Restitution,