12 THE TONER LECTURES. 



brain, the jjower of making gestures has been lost as well as in 

 case of disease of the left side of that organ. 



As regards the power of writing, there is a difficulty which 

 you will easily understand. Still there are many facts which 

 show that the power of writing can be lost more easily, and is 

 lost more frequently in cases of disease of the left side of the 

 brain than in cases of disease of the right side of the brain — a 

 difficulty which many of you have understood without my men- 

 tioning it. We conclude that the right arm is not rarely 

 paralyzed in diseases of the left side of the brain, and as we 

 write with the right arm, it is very natural that, on being 

 paralyzed, we cannot write ; but verj^ few patients have lost 

 altogether the movements of the fingers, and cannot form the 

 least sign, though many of them cannot at all form a letter. 

 They will.be able, however, if they have a letter written by 

 some one whose handwriting is not very much different from 

 theirs (and sometimes when it is different), they will be able to 

 imitate what is under their eye, but they cannot from memory 

 write anything; at all events, they cannot express ideas by 

 writing. They are attacked with what is called agraphia — 

 that is, a loss of the faculty of expressing ideas by writing. 

 In many of these cases of patients attacked with agraphia 

 there is a perfect power of moving the right arm. The arm is 

 not paralyzed in all cases where the left side of the brain is 

 paralyzed ; there is often no paralysis on the right side of the 

 body or the left; no paralysis anywhere. In these cases, it has 

 occurred sometimes that the patient could not write at all ; so 

 that it is clear that the loss of the faculty of expressing ideas 

 b}"- writing does not depend on the paralysis which in these 

 cases had no existence. 



Another thing depends on disease of the left side of the 

 brain more than the right side of the brain, and that is intelli- 

 gence. Alterations of the mind manifesting themselves in the 

 various forms of insanity depend more frequentlj-, I should 



