The illustration will give one an idea of the extraordinarily crabbed hand in which the notes are written, but it is worth while to see the original, for here is the first occasion upon which is laid down in clear and unequivocal words that the blood CIRCULATES. The lecture gave evidence of a skilled anatomist, well versed in the literature from Aristotle to Fabricius. In the MS. 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. To him, as to Vesalius before him, the current views of the movements of the blood were unsatisfactory, more particularly the movements of the heart and arteries, which were regarded as an active expansion by which they were filled with blood, like bellows with air. The question of the transmission of blood through the thick septum and the transference of air and blood from the lungs to the heart were secrets which he was desirous of searching out by means of experiment. (27) Harvey: Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus, Francofurti, 1628.