HARVEY. 37 ' distance from the heart swell and become distended ; whereas the contrary happens if you pass a liga- j|i lure round an artery. By this, and other similar reasonings, he demonstrated that the heart being excited to contract by the sthnulus of the blood, that fluid is impelled through the arteries, and I having served every purpose of secretion and nou- rishment, returns by the veins, to recommence its circulation. Great, however, as was the discovery of Harvey, his doctrine was not so complete and perfect in all its parts as it has since been ren- dered by the labours of later physiologists. In two points, his system must be acknowledged, even by his greatest admirers, to have been defective ; for he does not seem to have been aware of the con- tractile power of the coats of the arteries, nor to have thoroughly understood the minute connexion of the veins with the arteries. Harvey's work cost him twenty- six years to bring it to maturity ; his discovery was ill received, most persons opposed it, others said it was old, very few agreed with him. He had, indeed, his admirers ; witness, for example, certain verses which were addressed " To the Incomparable Dr. Harvey, on his Book of the Motion of the Heart and Blood," in which these lines occur : — There didst thou trace the blood, and first behold What dreams mistaken sages coined of old. For till thy Pegasus the fountain brake, The crimson blood was but a crimson lake. Which first from thee did tyde and motion gaine, And veins became its channel, not its chaine. With Drake andCa'ndish hence thy bays are curl'd, Fam'd circulator of the lesser world. But the epithet circulator, in its Latin invidious
