Doctrines Of The Circulation A History Of Physiological Opinion And Discovery In Regard To The Circulation Of The Blood

This historic book may have numerous typos and missing text. Purchasers can usually download a free scanned copy of the original book (without typos) from the publisher. Not indexed. Not illustrated. 1884 edition. Excerpt: ... Marcelli Malpighii Opera Omnia. Londini, 1686, tom, ii., p. 133. "parenchyma;" that is, of a semi-solid material, derived from sanguineous exudation, and not anatomically different from that of the liver or the spleen. But Malpighi found the whole of the pulmonary substance, attached to the bronchial tubes, to be "an aggregation of the finest and most delicate membranes, forming, by their extensions and sinuosities, innumerable rounded vesicles, like the cells of a honeycomb with their thin wax partitions." He discovered this structure by inflating the lungs, taken fresh from the recently killed animal, and observing with his magnifier (98) the distended vesicles on its surface: or still better, by first making the lung exsanguine with a watery injection, expelling the superfluous moisture by compression, then inflating the organ and drying it rapidly; when it became throughout so colorless and transparent that its vesicular texture could be seen both on the surface and internally. The repeated bifurcation of the bronchial tubes was also finely shown in such a preparation; and if the pulmonary artery, or one of its main divisions, were previously inflated and tied, its branches could be traced to their finest ramifications. An injection with mercury made these ramifications still more perceptible. But the experimenter could not succeed in finding the actual termination of the pulmonary bloodvessels; and he gives a striking picture of the difficulties met with by a pioneer in such matters. "Whether these vessels have a mutual anastomosis, either in the follicles or elsewhere, by which the blood gets to the vein through a continuous channel, or whether they open into the pulmonary substance, is an enigma which, so far, distracts my mind;...