of the thorax, or, as he calls it, the "parlour" lecture, there are about a hundred references to some twenty authors.

The remarkable thing is that although those lectures were repeated year by year, we have no evidence that they made any impression upon Harvey's contemporaries, so far, at least, as to excite discussions that led to publication.

It was not until twelve years later, 1628, that Harvey published in Frankfurt a small quarto volume of seventy-four pages,( 27) "De Motu Cordis." In comparison with the sumptuous "Fabrica" of Vesalius this is a trifling booklet; but if not its equal in bulk or typographical beauty (it is in fact very poorly printed), it is its counterpart in physiology, and did for that science what Vesalius had done for anatomy, though not in the same way.

The experimental spirit was abroad in the land, and as a student at Padua, Harvey must have had many opportunities of learning the technique of vivisection; but no one before his day had attempted an elaborate piece of experimental work deliberately planned to solve a problem relating to the most important single function of the body.

Herein lies the special merit of his work, from every page of which there breathes the modern spirit.