The elements of physiology : containing an explanation of the functions of the human body : in which the modern improvements in chemistry, galvanism, and other sciences, are applied to explain the actions of the animal economy / translated from the French of A. Richerand ... by Robert Kerrison.

  • Richerand, A. (Anthelme), 1779-1840.
Date:
1808
Catalogue details

Licence: Public Domain Mark

Credit: The elements of physiology : containing an explanation of the functions of the human body : in which the modern improvements in chemistry, galvanism, and other sciences, are applied to explain the actions of the animal economy / translated from the French of A. Richerand ... by Robert Kerrison. 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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    cantharides have a specific effect on the bladder, mercury on the salivary glands, &c. The relative magnitude of nerves in infants and women does not so well explain their great sensibility, as the softness of all their parts. Nerves, in fact, are smaller in men than in quadrupeds, in which they are employed for muscular actions, and seem rather to supply the function of nerves of motion than of nerves of sensation. Indeed we ought carefully to distinguish sensibility from sensation. The first is only a faculty; the other, on the con-^ trary, is a function. The former consists in an aptitude to be excited, impressed; the latter may be defined to be the impression itself that we experience from the contact of some body. (See the chapter on Sensations.) Contractility, Like sensibility, with which it is often so confounded that it is difficult to distinguish them, contractility is not uni- formly distributed over every part of the body, but graduated and modified in each. Thus in cellular membrane, lymphatic glands and vessels, it is discovered by a slow, involuntary, and gradual contraction, whilst in muscles it appears in evident contractions, by rapid oscillations, with swelling, induration, and contraction of these organs. One of these species of contractility is known by the name of tonic power, or tone; the other is called Hallerian irritability, or musculosity, because it is an attribute of the muscular fibre. These two modes are visibly but two modifications of one and the same property. Sometimes the skin, particularly that covering the scrotum, throws itself, from cold, into alternate contrac- tions and dilatations, which has a greater resemblance to musculosity, than that slow, gradual, and tonic-like ac- tion of the bladder on expelling urine. The most remark- able difference between these two kinds of contractility is, that one of them, at least in the generality of muscles, is