Experimental researches, illustrative of the functional oneness, unity, and diffusion, of nervous action, of four sets of nerves, and a fourfold set of functions, and transmitted impressions : with a brief exposition of the philosophy of vivisection, and of sensation / by Bennet Dowler.

  • Dowler, Bennet, 1797-1879.
Date:
[1851]
Catalogue details

Licence: Public Domain Mark

Credit: Experimental researches, illustrative of the functional oneness, unity, and diffusion, of nervous action, of four sets of nerves, and a fourfold set of functions, and transmitted impressions : with a brief exposition of the philosophy of vivisection, and of sensation / by Bennet Dowler. 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.)

    17/32
    Ihese parts, first leaving them in their ordinary state, and afterwards cutting them at their spinal extremities, to place them upon an isolating body. In these various cases, I obtained contractions from each sort of roots ; but those which followed the excitation of the anterior roots, were, in general, much stronger and more complete than those which took place when the electric current operated upon the posterior. * * * I repeated the experiments, after having separated the roots from the spinal marrow; and I ought to say, that, with the exception of two animals, in which I saw contractions upon pinching and pulling the an- terior and posterior bundles, in all the rest I did not observe any sen- sible effect from the irritation of the anterior or posterior roots thus separated from the spinal marrow. * * * The central parts of the spinal marrow may be touched, torn, even, we may say, with impunity, always taking the precaution necessary to avoid touching the surrounding medullary substance. I have several times plunged stylets through almost the whole length of the spinal marrow, without either the motions or the sensibility of the animal ap- pearing to be diminished. * * * Lesions of the cerebellum, do not cause loss of sensibility. The subtraction of the hemispheres does not necessarily cause the loss of motion. * * * Total ablations of the cerebellum do not cause a loss of sensibility. The cerebellum appears necessary to the integrity of movements forward. Sir Charles Bell, to whom the discovery of the double functions of the nerves has been attributed, (though unjustly,*) thus speaksf of the vivisection of their spinal roots: To expose these nerves near their origin, requires the operator to cut deep, to break up the bones, and to divide the bloodvessels. All such experiments are much better omitted ; they never can lead to satisfactory conclusions. * * * I have found it difficult to make the experiment without injuring both. * * * When the anterior roots singly, or the whole spinal nerve was pinched by the forceps, or pricked by the scissors, an evident motion was pro- duced on the muscles, not only perceptible to the eye, but when the third or fourth dorsal nerve was touched, the whole scapula moved in the hands of the assistant. ****** Anatomy is, as Bell affirms, better adapted for discovery than experiment. Although it is, to me, inconceivable how Sir Charles Bell's discovery could have been made *I have already proved that Mr. Alex. Walker preceded Bell, in the so called discovery of the double function of the nerves; the unanimity of the British and American writers to the contrary notwithstanding. If any more evidence be wanted to establish this, my protest, against one of the greatest historical falsehoods of the century, I am prepared to give it, without delay. fBell's Nerv. Syst.: passim.