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England was William Milbourn, who was curate of Brancespeth, near Durham, and who is stated to have made his way by himself to certain of the algebraic discoveries first published in Harriot's work, and likewise to have, by his own observations, detected the errors in the astronomical tables of Lansberg, and verified those of Kepler. The names of several other astronomical observers of less eminent merit who existed at this time in England have also been preserved; among which may be particularised that of Jeremiah Shackerly, the author of a work entitled Tabulae Britannica, published at London in 1653, which is stated to have been compiled mostly from papers left by Horrocks that were afterwards destroyed in the great fire of 1666.” Nor ought we to pass over the name of Edmund Gunter, the inventor of the useful wooden logarithmic scale still known by his name, and also of the sector and of the common surveyor's chain, and the author of several works, one of which, his Canon Triangulorum, first published at London in 1620, is the earliest printed table of logarithmic sines, &c., constructed on the improved or common system of logarithms. Briggs's tables, as has been stated above, were not printed till 1633. Gunter also appears to have been the author of the convenient terms cosine, cotangent, &c., for sine, tangent, &c., of the complement. “Whatever, in short,” as has been observed, “could be done by a well-informed and ready-witted person to make the new theory of logarithms more immediately available in practice to those who were not skilful mathematicians,

* See a notice of these English astronomers of the earlier half of the seventeenth century, in an article on Horrocks in the Penny Cyclopaedia, xii. 305.

WOL. IV. I

was done by Gunter.” He has moreover the credit of having been the first observer of the important fact of the variation of the compass itself varying. Another eminent English mathematician of this age was John Greaves, the author of the first good account of the Pyramids of Egypt, which he visited in 1638, and of various learned works relating to the Oriental astronomy and geography, and the weights and measures of the ancients. He died in 1652. Briggs, Gunter, Gellibrand, and Greaves were all at one time or other professors in the new establishment of Gresham College, London, which may be regarded as having considerably assisted the promotion of science in England in the early part of the seventeenth century. The founder, as is well known, was the eminent London merchant Sir Thomas Gresham, who died in 1579, and left his house in Bishopsgatestreet for the proposed seminary, although the reserved interest of his widow prevented his intentions from being carried into effect till after her decease in 1596. The seven branches of learning and science for which professorships were instituted were divinity, astronomy, music, geometry, law, physic, and rhetoric; the first four under the patronage of the corporation of the City of London, the three last under that of the Mercers' Company. The chair of geometry, in which Briggs and Greaves had sate, was occupied in a later age by Barrow and Hooke; and that of astronomy, in which Gellibrand had succeeded Gunter, was afterwards filled by Wren. Another Gresham professorship that has to boast of at least two distinguished names in the seventeenth century is that of music, which was first held by the * Penny Cyclopaedia, xi. 497.

famous Dr. John Bull, and afterwards by Sir William Petty.

HARVEY—THE CIRCULATION of THE BLooD ; ANAToMy, AND NATURAL HISTORY.

In the physical sciences, the event most glorious to England in this age is the discovery of the circulation of the blood by Dr. William-Harvey. To our illustrious countryman at least is indisputably due the demonstration and complete establishment of this fact, or what alone in a scientific sense is to be called its discovery, even if we admit all the importance that ever has been or can be claimed for the conjectures and partial anticipations of preceding speculators. Even Aristotle speaks of the blood flowing from the heart to all parts of the body; and Galen infers, from the valves in the pulmomary artery, its true course in passing through that vessel. After the revival of anatomy, Mondino and his successor Berenger taught nearly the same doctrine with regard to the passage of the blood from the right side of the heart to the lungs. Much nearer approaches were made to Harvey's discovery in the latter half of the sixteenth century. The famous Michael Servetus (put to death at Geneva for his anti-trinitarian heresies), in a work printed in 1553, distinctly describes the passage of the blood from the right to the left side of the heart, telling us that it does not take place, as commonly supposed, through the middle partition of the heart (the septum, which in fact is impervious), but in a highly artificial manner through the lungs, where it is changed to a bright colour; adding, that after it has thus been transferred from the arterial vein (that is, the pulmonary artery) to the venous artery (that is, the pulmonary vein), it is then diffused from the left ventricle of the heart throughout the arteries (or blood-vessels) of the whole body.” A few years after, in 1559, the pulmonary, or small circulation, as it is called, was again brought forward as an original discovery of his own by Realdus Columbus, in his work De Re Anatomica, published at Venice in that year. And, in 1571, Caesalpinus of Arezzo, in his Quaestiones Peripatetica, also published at Venice, inferred from the swelling of veins below ligatures that the blood must flow from these vessels to the heart. So far had the investigation of the subject, or rather speculation respecting it, proceeded when it was taken up by Harvey. From Fabricius ab Aquapendente, under whom he studied at Padua about the year 1600, Harvey, then in his twenty-second or twenty-third year, learned the fact of the existence of valves in many of the veins, which were evidently so constructed as to prevent the flow of blood in these vessels from the heart, and at the same time not to impede its motion in the opposite direction. According to Harvey’s own account, given in a

* This remarkable passage is often erroneously quoted from the Fifth Book of Servetus's first publication, entitled De Trinitatis Erroribus, which was printed, probably at Basle, in 1531. It occurs, in fact, in the Fifth book of the First Part of quite another work, his Christianismi Restitutio, published at Vienne in 1553. Of this work only one copy is known to be in existence, which has been minutely described by De Bure, who calls it the rarest of all books. See his Bibliographie Instructive, i. 418–422, where the passage relating to the circulation of the blood is extracted at length. It is remarkable, however, that what is believed to be the original manuscript, in the author's own handwriting, of the First Part of the Christianismi Restitutio also still survives. See De Bure, i. 423, 424.

conversation with Boyle, which the latter has reported in his treatise on Final Causes, it was the existence of these valves in the veins that first suggested to him the idea of his general theory of the circulation. Having satisfied himself by much consideration of the subject, and by many dissections and other careful experiments both on dead and living bodies, that his views were at least in the highest degree probable, he is supposed to have first announced the doctrine of the complete circulation of the blood from the left ventricle of the heart through the whole system back to the right by means of the arteries and veins, in his delivery of the Lumleian lectures on anatomy and surgery before the College of Physicians in 1615. But it was not till the year 1619 that he came before the world with the full demonstration of his theory in his treatise entitled “Exercitatio Anatomica de Motu Cordis et Sanguinis in Animalibus.” The best proof of the novelty of the views propounded in this work is furnished by the general incredulity with which they were received by the profession in every part of Europe. It is said that there was scarcely an instance known of the doctrine of the circulation being received on its first promulgation by any anatomist or medical man who had passed his fortieth year. It is probable, indeed, that even the small circulation, or the passage of the blood from the right to the left ventricle of the heart through the lungs, which was really all that had been hitherto discovered, was as yet but little known, or generally looked upon rather as at most an ingenious supposition than a well-established fact. At all events there can be no doubt that, beyond this point, all was darkness and error—that, notwithstanding some vague,

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