The fever of over-exertion / by J.F. Knott.

  • Knott, John, 1853-1921.
Date:
1888
Catalogue details

Licence: Public Domain Mark

Credit: The fever of over-exertion / by J.F. Knott. Source: Wellcome Collection.

Provider: This material has been provided by The Royal College of Surgeons of England. The original may be consulted at The Royal College of Surgeons of England.

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    rate of the heart's action, and marked rise of the arterial tension. We know that the application of such ganglionic stimulants, Avhen applied to centres ah-eady overstrained, is to overpower them com- pletely, and cause immediate vascular relaxation. There is every probability in the belief that the introduction into the circulation of uric acid, and, indeed, of many other products of rapid and perverted muscular metabolism is followed by the display of these phenomena in consecutive order. It is well known that the muscular system, as a whole, forms, even in health, the main factor in the production of heat vsdthin the animal system. It is the gi-eat furnace of the body; and, according to careful calculations, furnishes, during health, fully four-fifths of the total quantity of heat generated by the vital mechanism. The known relations between chemical transforma- tion and liberation of heat offers a satisfactory explanation of the dependence of the latter on the complex molecular changes that are constantly taking place in the unstable constituents of muscular structures. Increased muscular activity means, of course, increased chemical change; and, as it is always accompanied by elevation of temperature, the very natural assumption has usually been made— almost without question—that the production of heat was a simple function of the production of work, the former always varying directly as the latter quantity. More recent researches went to show that the connection was somewhat more complex, but attempts were made, vsdth apparent success, to define it in terms of a small number of variables. It was, however, reserved for my distin- guished friend, Dr. Donald Macalister, of Cambridge, to successfully differentiate the thermogenic from the motor function. Starting with the very simple fact that heat is produced by a resting muscle, and asking himself the obvious question, If heat is produced with- out contraction, may not contraction take place without heat? Macalister has shown by a series of ingenious experiments that fatigue from over-stimulation and exhaustion from long abstinence, each differentiated the thermogenic from the motor function. The muscle was always fatigued as a heat-producer before it was ex- hausted as a work-producer. Further investigation showed, on the