Lectures on the principles and practice of physic : delivered at King's College, London / by Thomas Watson.

  • Watson, Thomas, Sir, 1792-1882.
Date:
1845
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Licence: Public Domain Mark

Credit: Lectures on the principles and practice of physic : delivered at King's College, London / by Thomas Watson. Source: Wellcome Collection.

Provider: This material has been provided by the National Library of Medicine (U.S.), through the Medical Heritage Library. The original may be consulted at the National Library of Medicine (U.S.)

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    substance, is poured out into the same parts. When the central portion of the swelling softens and becomes pointed, this part of the whole enlargement is owing to the presence of a, quantity of pus. The different liquids that I have now been mentioning are of great importance, and play a conspicuous but diversified part in altering textures. Blood, serum, albuminous fluid or coagulable lymph, pus. They are called the products of inflammation. We are sure that inflammation lias been at work, if we meet with certain of these products. We are not sure that there has been inflammation if we perceive mere redness :—we are not always sure if we find serum only:—we are not sure if we find blood alone:—we are tolerably certain if we discover pus ; we are certain, at least, that there has been inflammation somewhere, though'doubts have been started whether the pus is not sometimes conveyed from an inflamed part to other parts of the body. We are qitife sure that there has been inflammation in a part if we find coagulable lymph in that part. This often remains, as a monument of the inflammation, during life; it frequently becomes organized, furnished with blood-vessels; and a great number of changes, some reparative, some morbid, depend upon its presence. I shall have to recur to these products of inflammation hereafter. The degree of swelling in different cases depends partly on the intensity of the inflammation, partly on the nature and texture of the structures affected. I need scarcely observe that swelling may exist without any inflammation. Hernia, simple anasarcous enlargements, dislocations, will occur to you as every day examples of swellings that have no necessary connection with inflammation. On the other hand, inflammation may exist without any appreciable swelling. Inflammation of the sclerotic coat of the eye, for instance, may be present, without any swelling cognizable by our senses. We have seen, in this review of the symptoms of inflammation, how much they severally depend, the pain, the swelling, the redness, and the heat, upon the increased influx of blood into the part. It may not be uninteresting to pause here for a moment to inquire what has been ascertained in respect to the actual condition of the capillaries of an inflamed part, and of the blood they contain. Much has been learned on these points by patient and minute observation with the microscope, and by reasoning upon the facts thus brought to light. Kaltenbrunner, Gendrin, Miiller, and others, have corrected many erroneous notions which formerly prevailed upon this subject. In order to comprehend the minute phenomena of inflammation, you must have a clear conception of the constituent elements of the blood, and of the main changes it is liable to undergo. The rough anatomy, rather than the chemistry of the blood, is what I allude to. The blood consists of red particles, or globules, and of a transparent colourless fluid called lymph, or liquor sanguinis. Miiller succeeded in separating these two constituents of the blood by filtering through paper that of a frog,°which contains very large red globules. The liquor sanguinis thus obtained separates spontaneously, by coagulation, into two parts, into serum and fibrin, the last having previously existed in solution in the liquor sanguinis. When the coagulation is suffered to take place without any attempt to remove the red particles, these are entangled and enclosed in the fibrin'as it becomes solid ; and the common well-known appearance of clot and serum results. You may even then wash out the red particles from the clot, and leave the fibrin. I must now recur to the experiments and observations of Kaltenbrunner. I should have told you, on a previous occasion, that various stimulant substances, mechanical or chemical, when applied to the web of a frog's foot, will produce irregular disturbances in the circulation, which irregular disturbances you are not to confound with true congestion: in like manner you must avoid confounding them with the phenomena of inflammation, which are always preceded bv those of true congestion. Kaltenbrunner found, likewise, that (just as in congestion) a certain interval of time generally happened between the application of the exciting cause and the apparent development of the inflammation. This accords