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.)

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    excepting two or three inches at its termination. The tail, (except its tip,) had, in becoming rigid, assumed a curved form; owing, it is sup- posed, to a partial dissection of its muscles on one side, made on the preceding day, whereby the muscular equilibrium had been destroyed. The convexity, accordingly, presented itself on the side that had under- gone mutilation. The site of the spinal vivisection had assumed an in- jected, vividly red appearance. The gall-bladder, which had been from the first, distended to its utmost capacity, remained unchanged—not having lost any of its bile by exosmosis, or transudation. The intes- tines were removed, opened, and examined. Their cut edges assumed irregular forms, and even retracted, so that their margins almost met; causing the mucous membrane to appear, in a great degree, as the ex- ternal surface. The arteries were empty—the cavas distended with dark blood, none of which had yet transuded. The limbs were made supple artificially, (as had been done formerly,) but on being left undis- turbed for one or two hours, they became rigid again. The experi- ments lasted seven hours, at the end of which time, no indications of vitality were apparent. Decapitation has great advantages over the usual method of stunning an animal by a blow on the occiput, preparatory to vivisection—an ad- vantage which seems to have been overlooked in solving the problem, whether the brain be the exclusive seat of sensational cognition. A stunning blow, to destroy sensibility, is but an equivocal proof of the destruction of the cerebral influence, (a destruction not compatible with sensational purposes,) since it is not possible to determine its ef- fects; whereas, in decapitation, the circumstances are easily enumera- ted and made known : that is, one decapitation is like another; but the force of a blow, the cranial resistance, and the effect, may differ, and give rise to complex, artificial conditions. The stunning of an animal, and its effects on the results of vivisection, cannot therefore, be appre- ciated with any certainty. No artificial perturbation, that can be avoided, ought to be introduced, especially such as are wholly inappre- ciable, not to say unnecessary and deceptive. In ascertaining the functions of an organ, either by the method of vivisection, or by that of morbid action, it must not be forgotten, that the process, though the best the nature of the case admits of, is, never- theless, to a certain extent, anti-physiological. Hence, the elements introduced by either method must not be fundamentally incompatible with the function sought; their influences and biases must be estimated, and, if it be possible, separated from the resultants properly functional. If the result sought for be purely normal, or purely pathological, the