The following year he was called by the Emperor Charles V to the court of Madrid, then the most brilliant in Europe, where he became the first physictan, and from this time abandoned his anatomical labors. [Illustration: 0126] He was the first who dared to dispute the words of Galen and point out his errors,--to ascertain that the greater{107} part of Galen's descriptions, having been made from monkeys, did not correctly represent human anatomy. This audacity raised a crowd of vehement opponents, the least reasonable and most fanatic being his old master, Sylvius; but even these onslaughts could not conceal the truth. The minds of men generally were ripe for the revolution whose signal-fire was thus lighted, and no sooner did Vesalius appeal from the decision of Galen to observation of nature than a crowd of anatomists were ready to follow his method. He died in 1564. One who, at Padua, had been first his pupil, then his co-laborer,--namely, Columbus, born at Cremona in 1490,--succeeded him. Columbus criticised, in some respects, the statements of his eminent predecessor, which he could better do, since he is said to have dissected fourteen bodies every year, as well as to have practiced venesection. He came so near to discovering the mystery of the circulation that it is strange how he could have missed it. He even appreciated the systole and diastole of the heart and the connection thereof with dilatation and contraction of the arteries. He knew, also, that the pulmonary veins conducted arterial blood, and that the pericardium was a shut sac. He even appreciated the lesser circulation, since he described how the blood left the right side of the heart and passed into the lungs, and came back through the veins into the left ventricle; because of this discovery, and in spite of his utter failure to appreciate the greater circulation, he has been by some regarded as entitled to the credit which is universally given to Harvey. From his position as teacher in Padua Columbus was called to Pisa, and from Pisa to Rome, where he died in 1559. [Illustration: 0128]