An inquiry into the comparative forces of the extensor and flexor muscles, connected with the joints of the human body / [Julius Jeffreys].

  • Jeffreys, Julius, 1801-1877.
Date:
1822
Catalogue details

Licence: Public Domain Mark

Credit: An inquiry into the comparative forces of the extensor and flexor muscles, connected with the joints of the human body / [Julius Jeffreys]. Source: Wellcome Collection.

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    I 47 The following question may possibly present itself on this explanation: from what cause does it arise, that when the extensors have yielded to the superincumbent weight, whether an addi¬ tional one, or that of the body, that the joints do not entirely give way, but the person is still able to support the weight, though staggering under it ? Richerand offers the following explanation:— The flexion of the knees is then limited by that .condition, in which the tendons of the extensors \ of the leg act on the tibia, at an angle sufficiently great to make up for their diminished energy.” > This is fallacious reasoning, and can contribute, , nothing to the intended purpose. The sophism, or deception consists in this, viz. that it makes a reference to a condition, which does not exist, and the supposition of which, is con¬ tradictory to the general proposition in mechanics, relative to the lever. Let ABC, be the thigh ; C.E D, the leg ;