Sept. 19, 1884.] 



♦ KNOWLEDGE ♦ 



229 



MACHINE OF SCIENCE 

 PlainlyWorded-ExactlyDescribed 



LONDON: FRIDAY, SEPT. 19, 1884. 



Contents op No. 151. 



PAGB 



Oar Two Brains. By Eichard A. 



Proctor 229 



An Aerial Propeller. (HUl,.) 230 



Pleasant Hours with the Microscope. 



\lllui.) By H. J. Slack £30 



Statiatit'S of Barataria. I. By 



Grant Allen 231 



The Workshop at Home. (Illug,) 



By a Workine Man 233 



The Earth's Shape and Motions. 



IV. Determinins; the Shape of 



the Earth (lUua.) By K. A. 



Proctor 234 



Dickens's Story left Halt Told. By 



Thomas Foster 235 



Emifrrants' Prospects in America. 



By W. E. Browne 230 



Electro-Pkting. XI. By W. 



Slingo 237 



Zodiacal Maps. (/«ii».) By E. A. 



Proctor 23S 



The British Association of Science 239 

 International Health Exhibition. 



XAT 241 



Dr. Kinns and his Friends 342 



Editorial Gossip S43 



Eeviews '.^43 



Miscellanea 244 



Correspondence 245 



Our Chess Colnmn 248 



OUR TWO BRAINS. 



By Richard A. Proctor, 



(Continued from page 190.) 



IN tte remarkable case -n-hich closed the last portion of 

 this article, one side of the brain had been so severely 

 injured that one might fairly have expected the mental 

 faculties would have suffered if the brain is to be regarded 

 as a single organ. Just as the proper work of an eye 

 cannot be done when one half of the eye is seriously in- 

 jured, nor the proper work of an arm if the upper or lower 

 arm is seriously injured, or the muscles on one side or the 

 other of the arm be torn or lacerated, so if the two sides of 

 the brain form but a single organ injury to one side must 

 in the most marked degree affect the power of the brain to 

 perform its proper work. Yet here was a case where one 

 side of the brain was so injured that manifestly the whole 

 of that side must have been disabled : yet the boy was able 

 to think as well as before, to move about with his customary 

 freedom of action, to do all in fine which he had been able 

 to do before he received the injury. 



In passing I note that there have been many remarkable 

 cases of the same kind, proving as much as this case did, 

 but not more. Among these cases, I may cite one not so 

 widely known as it deserves to be, — the case of the boy 

 McEvoy, who was killed by an accident in a saw-mill at 

 Paterson, N.J., somewhere about the spring of the year 

 1876, if I remember rightly. In that case, the boy had 

 stooped under the revolving saw, and partially rising, his 

 head came against the saw which cut through his hat into 

 the skull, so deeply that while one end of the opening was 

 only a little above the right eyebrow, the other end was 

 close to the crown of the head. In gauging the wound the 

 doctors were able to extend an instrument more than an inch 

 within the inner surface of the skull, near the middle of 

 the long gash. It was expected that the boy would be 

 dead before he reached the hospital ; but not only did he 

 survive the journey, but he was able to talk and was ap- 

 parently in full possession of his faculties a few hours after 

 the accident occurred. He lived till the fifth day. and his 

 death then was sudden and unexpected, due apparently to 



inflammation caused by the presence of fragments of the 

 torn hat within the wound. During the last two days, the 

 doctors who before had had no hope of the boy's recovery, 

 took a .sanguine view of the case. He was certainly in full 

 possession of his mental faculties up to within a few hours 

 before he died. Unfortunately the boy's mother would 

 not allow a post-mortem examination to be made, so that it 

 was impossible to say how deeply the saw had really pene- 

 trated into the boy's brain. 



In the next case cited by Dr. Wigan, it was found during 

 post-mortem examination of a patient of his own that one 

 hemisphere of the brain was entirely gone. Yet the patient, 

 a man about fifty years of age, had conversed rationally and 

 even written verses, within a few days of his death. The 

 evidence here is more decisive than in either of the cases 

 just considered ; for in those cases one-half of the brain 

 though seriously injured was yet not destroyed and one 

 might imagine that some of the functions of that half 

 might continue to be discharged, severe though the injury 

 was. But where one hemisphere was found to have been 

 entirely absorbed before death, it is impossible to explain 

 the possession of reasoning powers within a few days of 

 death, unless we suppose one-half of the brain sufficient 

 for the full exercise of the mental faculties. 



But the following case is still more remarkable : — 



A gentleman came to the celebrated Dr. Conolly, under 

 the following circumstances. He had applied a very strong 

 embrocation to the cheek for some ailment there, and an 

 inflammatory disease had been caused by its action. This 

 disease spreading through the eye orbit had affected the 

 brain, and when he applied to Dr. Conolly the case was in 

 reality hopeless. By slow degrees the disease prevailed. 

 A post-mortem examination showed that one hemisphere of 

 the brain was " entii'ely destroyed — gone, annihilated — and 

 in its place," says Dr. Conolly, "a yawning chasm." " All 

 the man's mental faculties were apparently quite perfect." 

 His nurse (and landlady) whom alone he permitted to 

 attend upon him, declared that his mind was clear and un- 

 disturbed to within a few hours of his death. " He had a 

 perfect idea of his own awful situation, and his landlady — 

 having been gradually accustomed to the sight of horror — 

 was alone allowed to come near him. He would not even 

 permit his own sister or other relatives to witness his 

 frightful condition." 



Dr. James Johnson mentioned to Dr. Wigan the case of 

 a gentleman who came under his care, " who retained the 

 entire possession of his faculties to the last day of his 

 existence, yet on opening his skull, it was found that one 

 cerebrum was reduced by absorption to a thin membrane — 

 the whole solid contents of one half of the cranium, above 

 the tentorium, absolutely gone." This gentleman showed 

 no sign of mental weakness, but he was subject — it will 

 not be much wondered at — to epileptic fits. 



In the next case to be considered, it was made clear on 

 a post-)nortem examination that the only active part of the 

 brain had been the right cerebrum. The convolutions of 

 the left cerebrum were in so diseased a state that when the 

 brain was removed from its case a large quantity of serous 

 liquid escaped from the left side, and the mass was reduced 

 to one-third its former amount, and to about one-fourth 

 that of the right side. In this case there had been partial 

 paralysis of the right side, showing how the left brain 

 governs chiefly the motor system of the right side of the 

 body. This partial paralysis had existed from childhood ; 

 and the paralysed members were wasted and atrophied. 

 But the intellectual faculties were entire, the patient pos- 

 sessed the use of his senses, and was able to walk with the 

 help of a stick. 



In Cruveilhier's "Anatomie Patho'ogque du C. rp3 



