190 



KNOWLEDGE ♦ 



[Sept. 5, 1884. 



forward, and its median plane is of course vertical. It is 

 called tlie fal.c cerebri. A large lateral expansion of the 

 falx — called the tentorium — separates the posterior lobes of 

 the cerebrum from the cerebellum, extending over the latter 

 like a vaulted floor. It protects the cerebellum from the 

 pressure of the hinder part of the cerebrum.* The central 

 hemisjiheres are separated below by two cavities termed the 

 lateral ventricles. There are other smaller cavities called 

 respectively the third ventricle, and the ventricle of the 

 cerebellum. The last-named is of considerable extent, and 

 occupies the space between the cerebrum, the commissure 

 of the cerebrum, and the medulla oblongata, the portions 

 of the nervous mass lying at the base of the cranial cavity, 

 between the cerebrum and the cerebellum. 



It should be added that from the upper surface of th^^ 

 convolutions, fibres descend to the medulla oblongata, 

 where they form the corpora pyramidalia and decussate 

 or cross over from one side to the other. This interesting 

 fact was first established by Drs. Gall and Spurzheira. It 

 follows that the right brain rules the left side of the body, 

 and the left brain the right side. In agreement with this 

 is the fact that if one side of the brain suffers it is the 

 opposite side of the body which is alone affected. 



I have said so much respecting the parts of the brain 

 rather that the cases which will have presently to be 

 •quoted may bi^ fully understood, than with any idea of 

 giving even in outline an account of the exceedingly com- 

 plex; structure which appears to regulate thought, sensa- 

 tion, and motion. 



We have now to consider the evidence tending to show 

 that each of the so-called " hemispheres of the braiu " is 

 an independent [orgau of thought, in the same sense that 

 each eye is an independent organ of vision. 



The first point to be noted is that one side of the brain 

 may suffer the most serious mischief, or even be destroyed, 

 -without any marked injury to the mental functions. 



Dr. Wigan mentions the following case as that which 

 first attracted his attention to the duality of the brain : — 

 ' A boy, in climbing a high tree for a rook's nest, missed 

 his footing, and fell on the sharp edge of an iron railway, 

 one of the earliest laid down in this country, and on a 

 different principle from those now in use, the wheel passing 

 in a sort of groove, instead of on the edge of a projection. 

 The side of the iron rail stood up, and was exposed to the 

 ■friction of the outer side of the wheel, which soon wore it 

 to a sharp edge. The boy fell head-downwards on this ; it 

 entered about an inch from the falx and sliced off a large 

 portion of brain, with nearly the whole of the parietal 

 bone ; much of the brain being torn and ragged, I pared 

 off the projecting fragments aud replaced the mass, not 

 having the slightest hope of his recovery, and only occupy- 

 ing myself with the task of laying on plasters and 

 bandages to appease the anxiety of the friends. The 

 quantity of the brain lost must have exceeded four ounces, 

 but my recollection of the case is vague after an interval 

 of more than thirty years. Having always read that the 

 integrity of both hemispheres was essential to the due 

 «xercise of mind, I was much astonished the next day to 



* Wigan makes the following remarks on the Falx and the Tento- 

 Tiunj : — The object of these membranes, which are as tightly 

 stretched as the akin of a drum, seems to be to prevent the mis- 

 v.hievous con^pfpi^nces of the concussion of the brain in sudden 

 movements; a> jumping, for example — the elastic membrane gives 

 w.ay to the impKi.M-. and thus diminishes the shock. The falx is 

 also of great utility iu preventing the pressure of one brain on the 

 other in lying down j and the transverse membrane, called the 

 tentorium, performs a similar office j it forms a kind of tent (whence 

 its name), and covers a deep hollow in the back of the skull, which 

 contains the cerebellum, and thus preserves it from the pressure of 

 Jthc fniJCiincumbci.l mass of cerebrum. 



find the patient (a remarkably intelligent lad, of twelve or 

 thirteen years of age) in the full possession of his faculties 

 in as high a degree as at any former period. He did not 

 seem to suffer pain, — had no delirium, — and advanced 

 steadily towards recovery ; considerable new growth took 

 place ; but of its nature I have no recollection ; it was 

 probably fungous ; at the end of a few weeks he was so 

 well that, in spite of the remonstrances of his mother, he 

 went into the field to play ; became exceedingly heated 

 by this, under exposure to a violent sun, and then walked 

 deliberately into the water to cool himself. The new blood- 

 vessels burst, and he died of haamorrhage ; never having 

 manifested from first to last any loss or perversion of mental 

 power." 



It seems impossible to doubt that in this case the part 

 of the brain which was destroyed was large enough and 

 important enough to have seriously affected the mental 

 power had the brain been a single organ. Nay, it would 

 seem probable that just as one eye would be rendered for 

 a while entirely useless by some serious injury, so the whole 

 half of the brain, on the side which had suffered injury, 

 must for a time have been useless. Therefore as the boy 

 showed no loss of mental power, the other half must have 

 been a perfect brain in itself 



Let us consider, however, some cases which seem still 

 more decisive. 



{To be continued.) 



DREAMS: 



THEIE PLACE IN THE GROWTH OF PBIMITIVB 

 BELIEFS. 



Br Edward Clodd. 



VIII. 



IN proof of the closing remarks in the previous paper, 

 that the breath has given the chief name to the soul, 

 we find the Western Australians using the same word, 

 waiig, for " breath, spirit, soul ; " in Java the word naxva 

 is used for " health, life, soul ; " in the Dakotah tongue 

 jiiya is literally "breath," figuratively "life;" in Netela 

 jmits is " breath " and " soul ; " in Eskimo silla means air 

 and wind, and is also the word that conveys the highest 

 idea of the world as a whole, and of the resisoning faculty. 

 The supreme existence they call Sillain Innua, Owner of 

 the Air, or of the All ; in the Yakama tongue of Oregon 

 wkrisha signifies there is wind, vkrishwit, life ; with the 

 Aztecs eJiecatl expressed both air, life, and the soul, and, 

 personified in their myths, it was said to have been born of 

 the breath of Tezcatlipoca, their highest divinity, who 

 himself is often called YoalliehecatI, the Wind of Night.* 

 This identity of wind with breath, of breath with spirit, 

 and thence of spirit with the Great Spirit, which 



Sees him in cloud, and hears him in the wind, 

 has further illustration in the legends of the Quiches, in 

 which the unknown creative power is Hurakan, a name 

 familiar to us under the form hurrieane, and in our own 

 sacred records where the advent of the Holy Spirit is described 

 "asof a rushing, mighty wind. "t In the Mohawk language 

 atonritz, the "soul," is from atonrion, "to breathe"; 

 whilst, as showing the analogy between the effects of 

 restricted sense and restricted civilisation, Dr. Tylor quotes 

 the case of a giil who was a deaf-mute as well as blind, 

 and who, when telling a dream in gesture-language, said : 



» Brinton's "Myths of the New World," p. 51. (Second Edition.) 

 + Cf. Knowlefge, June 1, 1SS3, p. 321. 



