Page:The Harveian oration - delivered at the Royal College of Physicians June 24, 1882 - by George Johnson (IA b21517046).pdf/19

15 suggestion, the work of Fabricius ("De Venarum Ostiolis'), which was published in 1603, a year after Harvey's departure from Padua, and rather more than thirty years after the publication of Cesalpino's chief treatise (Quæstionum Peripa- teticarum libri quinque,' Florent. 1571), affords conclusive evidence of its author's entire ignorance of the circulation of the blood through the systemic vessels.

Fabricius believed that the purpose of the valves in the veins was not to favour the passage of blood to the heart, but to prevent over-distension of the veins by the blood in its passage through the venous trunks to their branches, and also to retard the current of blood, so that time might be given for each part to take up its proper nutriment; and he states that valves are not required in the arteries, because, on account of the thickness and strength of their coats, they are not liable to be over-distended. Neither are valves required to retard the stream of blood, because in the arteries there is a perpetual flux and reflux apprendere la dottrina novella da Fabrizio d'Acquapendente, al quale il grido di anatomico sommo chiamava scolari anche da oltralpe,' pp. 18, 19.