CLASS IV. 2. 3. i. OF ASSOCIATION. 4*3 



ORDO II. 



Decreafed AJficiate Motions* 



GENUS III. 



Catenated with Voluntary Motions. 

 SPECIES. 



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

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

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

 tions, as by awe, baiM ulnefs, ambition of mining, or fear of not 

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

 gain the broken aflbciations, as explained in Seel. XVII. i. 10. 

 and XVII. 2. 10. 



The broken afibciation 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 defel is to caufe the flam- 

 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 hefitates 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 ftill in bed, which (hews the motions not to be 

 convulfive ; and he can at different times voluntarily exert every 

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

 In this difeafe the principal mufcle in any defigned motion obeys 

 the will $ but thofe mulcles, whofe motions were aflbciated with 

 the principal one, do not al ; as their aflbciation is diflevered, 

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

 ward, inilead of upward or forward, with various geiliculations 

 exactly refembling the impediment of fpeech. 



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

 cured. See ctfnvulfio dolorifica, Clafs III. i. i. 6. A girl 

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



acquired 



