Class IV. 2. 3. 1. OF ASSOCIATION. 423 



ORDO II. 



Decreafed Ajfociate Motions, 



GENUS III. 



Catenated with Voluntary Motions. 



SPECIES. 



1. Titubatio lingua. Impediment of fpeech is owing to the 

 afibciations of the motions of the organs of fpeech being inter- 

 rupted or diffevered by ill-employed fenfation or fenfitive mo- 

 tions, as by awe, bafhfulnefs, ambition of mining, or fear of not 

 fucceeding, and the perfon ufes voluntary efforts in vain to re- 

 gain the broken affociations, as explained in Seel;. XVII. 1. 10. 

 and XVII. 2. 10. 



The broken aflbciation is generally between the firft confo- 

 nant and the fucceeding vowel ; as in endeavouring to pronounce 

 the word parable, the p is voluntarily repeated again and again, 

 but the remainder of the word does not follow, becaufe the af- 

 fociation between it and the next vowel is diflevered. 



M. M. The art of curing this defect is to caufe the Ham- 

 merer to repeat the word, which he finds difficult to fpeak, 

 eight or ten times without the initial letter, in a ftrong voice, or 

 with an afpirate before it, as arable, or harable ; and at length 

 to fpeak it very foftly with the initial letter p, parable. This 

 (hould be praclifed for weeks or months upon every word, 

 which the Hammerer helitates in pronouncing. To this mould 

 be added much commerce with mankind, in order to acquire 

 a careleflhefs about the opinions of others. 



2. Chorea Sti Viti. In the St. Vitus's dance the patient can 

 at any time lie (till in bed, which fhews the motions not to be 

 convulfive : and he can at different times voluntarily exert everv 

 mufcle of his body \ which evinces, that they are not paralytic. 

 In this difeafe the principal mufcle in any designed motion obeys 

 the will ; but thofe mufcles, whofe motions were afTociated with 

 the principal one, do not ac~t 5 as their affociation is difTevered, 

 and thus the arm or leg is drawn outward, or inward, or back- 

 ward, in (lead of upward or forward, with various gefticulations 

 exactly refembling the impediment of fpeech. 



This difeafe is frequently left after the itch has been too haftily 

 cured. See convulfio dolorifica, Clafs III. I. \. 6. A girl 

 about eighteen, after wearing a mercurial girdle to cure the itch, 



acquired 



