lOG 



♦ KNO^VLEDGE ♦ 



[Aug. 7, 1885. 



the rounded forms of summer clouds, and we see in eacli 

 case liow tendencies towards or from a centre result in 

 giving imiformity of stape to the aggregation of matter 

 resulting from such tendencies. The existence of a shape 

 centrally symmetrical, whether circular or elliptical, 

 implies in every case the existence of forces tending 

 cither fi"om or towai'ds a centre. I know of no exception 

 to this rule in nature, though of course artificial produc- 

 tions may show symmetrical forms without giving 

 evidence of central forces. 



We may as.sume then that whatever were the forces at 

 work in forming and maintaining the great red spot on 

 Jupiter, they were related in some way to the centre of 

 the oval region affected by them. They may have pro- 

 duced motion fi-om that centre, or motion towards it, or 

 there may have been movements of both sorts : but 

 assuredly central forces were at work in some way or 

 ways, where the great red spot was formed. 



While the symmetry of the spot's shape forces on us 

 this general conclusion, the greater length of the spot in 

 one direction than in another possesses also a special 

 significance. 



(To be continKed.) 



THOUGHT AND LAXGUAGB. 



By Ada S. Ballik. 



IHA'V'E spoken at considerable length of the deaf and 

 dumb, a class shut off from the use of articulate 

 speech by physical inability, which may, to a certain 

 extent, be overcome by long years of patient teaching on 

 the oral system, but I have now to speak of a class of 

 unfortunates who, although b}- no means idiotic, are, 

 through brain disease, deprived of the use of verbal 

 language. In this class I do not include those cases where 

 the power of using language is lost, but that of under- 

 standing it is retained, or such cases as the following, men- 

 tioned by the late Sir Benjamin Brodie — ^the case of a 

 gentleman, who, two years after an apoplectic stroke, 

 suddenly lost the power of speaking and of understanding 

 articulate speech, while still able to read and write. A 

 letter read to him conveyed no ideas to his mind, but if 

 he read it himself he understood it perfectly. He reco- 

 vered from this attack, but had a similar one afterwards. 

 Although these are of great interest from a pathological 

 point of view, they do not imply loss of control over 

 language as such. 



In the understanding and production of language many 

 brain centres are implicated,* but its intelligent use is 

 dependent on a comparative!}- small cerebral area, 

 namely, the posterior half of the third frontal convolu- 

 tion, as it is called Broca's Convolution, and especially 

 that of the left hemisphere. This is supported by the 

 fact that some degree of right-side paralysis generally 

 co-exists with the affection of the faculty of speech by 

 brain disease. Movements of the right side of the body 

 are dependent on action of the left side of the brain, and 

 the development of the left hemisphere corresponds to 

 the superior activity of the right hand over that of the 

 left. In the compai-atively rare cases of left-handed 

 persons the right side of the brain has attained the 

 higher development, and in these cases when left-side 

 paralysis co-exists with injury to the faculty of speech 



2)ost-moriij>ji examination reveals damage to Broca's Con- 

 volution on the right side. Injury to the brain-centres 

 on which language depends may exist in any degree of 



severity, from more functinnnl nffectinn tn total dcstmc- 



c' - 1 ', ( " ■ ' ' !■: 



matter. He could not 

 It icas iDqwssible to get 

 • le could only 



,-v f.-w ^v..rds 



beg 



.ssed a 



by his u 



tllr 



retained 



inform his medical atWi, i^i •. J';. Ki! 1, iImi lii-^ li^ttle 

 of liniment was neaily tiji|.iy. Lc .^,iiil. " Bring the 

 cord ; " at another time he spoke of the pills he had 

 been taking as "potatoes." One day, when giving his 

 waistcoat to be put away, with his watch in the 

 pocket, he said : " Take care of the break-fall." He was 

 quite deaf. His power.s of speaking and writing varied 

 at different times; the letters sometimes containing 

 properly-written words, but being almost unintelligible. 

 He wrote his address several times on different sheets 

 of paper, but some of the words were imperfect. "My 

 dear sir" was written correctly, but the sheet was 

 filled with meaningless writing, only the one word, 

 "wife," being legible until the signature, which was in 

 his usual hand. An indication that his intelligence was 

 fairly retained in given by the fact that at the time 

 when a remittance was due from his agent he was much 

 excited every morning, asking often for something. At 

 last it occurred to one of the family to show him his 

 agent's letter. This pleased him : biit he was not quite 

 satisfied until the money was brought and counted in 

 hLs presence. Some shillings were not shown him at 

 first, but when he saw them he seemed to know all was 



Case 2. — A much more severe case is related by Dr. 

 Broadbentf of a painter, aged 42. His speech was a 

 mere jabber, in which " Ma " and " Mum " were promi- 

 nent ; it was accompanied with excessive gesticulation, 

 smiles, and facial expression. He seemed not to recog- 

 nise the state of his speech, for he continued to jabber as 

 if he thought lir «a> unrler^to.rl ; but Ik- also made 

 signs. "Til. . - 1, : • . -Aire very 



striking, win i ... It 



was stated tl:^ i !iiy ! ' at 



times; but li i If words 



before us." He cuuld not write intL-Uigibly, nor even 

 copy his own signature. He did not understand what 

 was said to him, and repeatedly put out his tongue when 

 told to close his eyes ; but imitated the desired act after 

 Dr. Felee. 



Case 3. — Trousseau mentions the case of a lady who 

 was very rational in her actions, but used words quite 

 irrelevaii!^;, \. itli.,;!t |i. r.- i-, h; - ir. She rose courteouslj- 

 to ri r. : , '. ; ■• ■ r _ to a chair, said, 



"Corl. , , , ■' ' . !,i,-h her son-in-law 



explain.-! I, --.i!,^-. -M -lina- v,.u> invite k vous 



Case 4. A striking case of complete loss of control 

 over language, with retention of the power of under- 

 standing it and of intelligence as shown by actions and 

 gestures, is that of il. X , roc-nr.h-d bv Tr. -usseau, who 



* Dublin Quarterly Journal of ilcdi.-il >,■;,-„,■., F.ljruary, 1865, 

 p. 78. I number the cases qtioted here to facilitate the references 

 which will be made to them in the succeeding article. 



t iTedico-Chirurgical Transactions, 1872, p. 170. 



