The nervous system, anatomical and physiological : in which the functions of the various parts of the brain are for the first time assigned: and to which is prefixed some account of the author's earliest discoveries, of which the more recent doctrine of Bell, Magendi, etc. is shown to be one.

  • Walker, Alexander.
Date:
1834
Catalogue details

Licence: Public Domain Mark

Credit: The nervous system, anatomical and physiological : in which the functions of the various parts of the brain are for the first time assigned: and to which is prefixed some account of the author's earliest discoveries, of which the more recent doctrine of Bell, Magendi, etc. is shown to be one. Source: Wellcome Collection.

Provider: This material has been provided by UCL Library Services. The original may be consulted at UCL (University College London)

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    those of volition, the writer was, in some mea- sure, led by the fundamental fact just now which however it exceeds in consistence. It contains just so much nervous matter as is necessary to form about sixty pair of nerves, which are distributed to each part according to its demands for nervous energy. Nerves have three uses : to communicate to the organs of sense their respective sentient faculties; to excite motion in the organs of motion ; and to enable the organs of the body in general to discern what might be injurious to them. (De JJsu Part. lib. v. c. 9.) The nerves of the senses are soft, like the part of the brain from which they are derived; they all rise from the anterior part, and pursue a straight course to the organs which they supply. The motory nerves are hard, arising from the posterior part of the brain, and the whole of the spinal marrow: these pursue a circuitous course to the parts to which they are distributed. Although Galen thus recognised a distinction between the sensatory and motory nerves, he conceived that this dif- ference of function arose merely from difference of consist- ence. His idea appears to have been a mechanical one,— that the soft nerves were more susceptible of impressions, and the hard nerves less impressible, but stronger, and therefore better fitted for action. He had not the smallest notion of any original difference in the nature of the nervous power communicated by the two classes of nerves, nor that the parts of the central mass from which they spring were respectively the depositories of a sensific and a motific prin- ciple, distinct in their nature, and dependent on different modifications of the vital power. That he was entirely ignorant of all this, is evident from his maintaining that the hard motory nerves, although comparatively insusceptible