Cerebral physiology and materialism, with the result of the application of animal magnetism to the cerebral organs, an address... / by W.C. Engledue ; with a letter from Dr. Elliotson, on mesmeric phrenology and materialism.

  • Engledue, W. C. (William Collins), 1814-1859
Date:
1842
Catalogue details

Licence: Public Domain Mark

Credit: Cerebral physiology and materialism, with the result of the application of animal magnetism to the cerebral organs, an address... / by W.C. Engledue ; with a letter from Dr. Elliotson, on mesmeric phrenology and materialism. Source: Wellcome Collection.

    15/38 page 15
    In the lowest class, the Infusoria, the tissues appear to be homo- geneous—there seems to he an absence of cognizable nervous matter. But we must not forget the fact, that our failure to detect is no proof of non-existence. Even in the human eye, the arrangement of nervous matter called retina would not be visible, if it were not for the other tissues entering into its composition: hence, we learn that it is quite possible to conceive the existence of nervous matter, although of a nature so transparent and unmixed, that it remains in¬ visible to our senses. Analogy would lead us to conclude that there is a nervous system in these tribes. How can we avoid the belief, when, notwithstanding their excessive minuteness, requiring a mi¬ croscope to display them, we see them discriminate and seize their prey—contract and bend their bodies in every direction—appear conscious of each other’s approach—in fact, perform movements with as much regularity and precision as animals which undeniably possess a nervous system. From recent researches it becomes more and more probable that we shall soon be in a position to demonstrate the nervous system in all the infusoria, without distinction. However, to discard doubtful points: as we proceed to investigate higher tribes, we find nervous matter assuming regular and deter¬ minate forms. We perceive ganglionic centres arranged exactly where they are required; and in the centres of these ganglia we find particles of grey matter, which we shall presently see are considered to be the source of power in the higher order of brains. If great locomotive powers are necessary, ganglia are placed in the neigh¬ bourhood of the organs destined to serve this purpose. If powerful digestive organs are required, nervous energy is supplied by an assemblage of ganglia round the digestive apparatus. In some a considerable portion of nervous matter is above the oesophagus, and may be considered analogous to the brain of higher animals. In this way we may investigate, till we arrive at the Vertebrate classes, where we find cerebral lobes and a Cerebellum. Now, in proportion as we ascend in the scale, we observe increased development of these portions, and a greater amount of intelligence; in fact, more ex¬ tended Cerebration. The surface of the hemisphere becomes convo¬ luted, and the arrangement of the white portions increases in com¬ plexity. In the brain of the fish there is a want of that concentration so characteristic of the nervous structure of the higher orders. Every nerve terminates in a distinct and appropriate ganglion, and hence the peculiar appearance. In reptiles we observe a considerable development in the cerebral
    digitised image 1
    digitised image 2
    digitised image 3