Physiological therapeutics : a new theory / by Thomas W. Poole.

  • Poole, Thomas W.
Date:
1879
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Licence: Public Domain Mark

Credit: Physiological therapeutics : a new theory / by Thomas W. Poole. Source: Wellcome Collection.

Provider: This material has been provided by the Francis A. Countway Library of Medicine, through the Medical Heritage Library. The original may be consulted at the Francis A. Countway Library of Medicine, Harvard Medical School.

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    ADDENDA. Note to § 81, page 40.—We have been asked, by way of friendly criticism, if the converse of what is here stated holds good where the muscle is contracted, instead of relaxed, at the moment when the mo- tor nerve is severed. We do not pretend that the muscles would neces- sarily remain contracted, after section of their motor nerves, when con- tracted previously, at least in ordinary cases. During conscious- ness, mental emotion in man, and in the inferior animals, terror, would doubtless vitiate such a result, by ii?tvoluntarily causing a re- versal of the molecular nerve arrangements, before the motor nerve^ or all the motor nerve communications, were cut across. There may also be unknown differences in the character or intensity of the molecular arrangements for inducing contraction and relaxation of muscle respectively, which come into play under such circumstances,^ and modify the result. There is, however, abundant proof that muscular contraction, vol- untarily induced, continues after the cessation of the action of motor nerve-force. Thus drowning men, not only catch at straws, but hold them. As is well known, small objects, as gravel, sand, a few hairs or a bit of clothing, seized in the last moments of life, have been firmly retained in the grasp: as have also the bodies of per- sons drowned together. Those who object to our theory, must ex- plain how the firm contraction of the muscles is maintained in these cases, after the extinction of nerve-force, and before the setting ia of rigor mortis : as well as the numerous other instances mention- ed in these pages, of post mortem contractions of muscular fibre, as in the arteries and hollow viscera. Dr. Alfred S. Taylor even intimates the possibility of a dead body being found still holding to a rope, cable, or oar,* and elsewhere he writes, '• It may be remarked, that muscles, contracted by living force, in the act of dying, do not necessarily become relaxed in death.-f* If this be true, then what we have predicated of molecular polar nerve-force, when adjusted for relaxation, is shewn to apply also, under certain conditions, to the adjustment of the same force for muscular contraction : that is, that nerve-force maintains a fix- edness or permanency in both cases, when not reversed by volun- tary impulses from the central motor ganglia. Note to § 126,. page 63.—An additional point of distinction between nerve-force and electricity, is to be found in their respective rate of motion. Thus, nerve-force moves at an average, in man, at a speed of only about one hundred feet per second ;| while the rapidity of electricity is, of course, immeasurably greater. * Medical jurisprudence, 6th Amer. Ed., p. 327. flbid, p. 58. i^rDrs. Beard and Rockwell, Med. and Surg. Elec, p. 208.