On diseases of the chest : being contributions to their clinical history, pathology, and treatment / by A.T.H. Waters.

Date:
1868
Catalogue details

Licence: Public Domain Mark

Credit: On diseases of the chest : being contributions to their clinical history, pathology, and treatment / by A.T.H. Waters. Source: Wellcome Collection.

Provider: This material has been provided by the Royal College of Physicians of Edinburgh. The original may be consulted at the Royal College of Physicians of Edinburgh.

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    of a broncliial tube by a circular opening, which is usually smaller than the sac itself, and has sometimes the appear- ance of a circular hole in a diaphragm, or as if it had been punched out of a membrane stretched across the entrance to the sac. When this is the case, the sac dilates suddenly beyond the opening. The sacs of the lobulette are placed side by side, and are separated from each other by thin membranous walls. Their shape, when properly inflated, or when distended by some material which has set in them, as gelatine, or a mixture of wax and tui'pentine, is polygonal. They approach the circular in form; but, in consequence of mutual pressure, the parietes become some- what flattened. The sacs increase slightly in size as they pass from the bronchial tube to their fundus, the latter being usually the broadest part of the sacs; but they often have an almost uniform diameter throughout. All the sacs pass from the extremity of the bronchial tube towards the circum- ference of the lobule of which the lobulette forms a part ; they consequently radiate from the tip of the bronchial twig. The sacs connected with one lobulette do not com- municate with those of another lobulette. As the sacs pass towards the boundary of the lobulette, they often bifurcate; and here and there circular orifices exist, leading to smaller air-sacs. If we trace the air-sacs from their fundus, we may say that, passing from the periphery of the lobulette, and diminishing somewhat in size, they all terminate in the dilated extremity of the bronchial tube; as they thus proceed, they often join, two or three together, and these terminate in a single mouth. The tube which results from the union of two or more sacs is smaller in capacity than the sacs taken together, but greater than either of them individually. The dilated extremity of the bronchial tube, above alluded to, constitutes the jpoint de rdunion of all the air-sacs, and may be considered as the common centre of the