*< IRRTTATIVE Sect. VIL r. 4, 



beginning of fomc fevers this irritation of the mufcles produces 

 perpetual ftretching and yawning •, in other periods of fever an 

 univerial reftlefTnefs arifes from the fame caufe, the patient 

 changing the attitude of his body every minute. The repeated 

 ftruggles of the fcetus in the uterus mult be owing to this inter- 

 nal irritation : for the foetus can have no other inducement to 

 move its limbs but the tsedium or irkfomenefs of a continued 

 pofture. 



The fcllowing cafe evinces, that the motions of ftretching the 

 limbs after a continued attitude are not alwavs owine to 

 the power of the will. Mr. Dean, a mafon, of Auftry, in 

 Leicefterfhire, had the fpine of the third vertebra of the back 

 enlarged ; in fome weeks his lower extremities became feeble, 

 2nd at length quite paralytic : neither the pain of blifters, the 

 heat of fomentations, nor the utmoft efforts of the will could 

 produce the leaft motion in thefe limbs ; yet twice or thrice a 

 day for many months his feet, legs, and thighs, were arretted 

 for many minutes with forcible flretchings, attended with the 

 fenfation of fatigue ; and he at length recovered the ufe of his 

 limbs, though the fpine continued protuberant. The fame cir- 

 cumftance is frequently {ten in a lefs degree in the common 

 hemiplegia ; and when this happens, I have believed repeated 

 and ftrong (Locks of electricity to have been of great advantage. 



4. In like manner the various organs of fenfe are originally 

 excited into motion by various external ltimuli adapted to this 

 purpofe, which motions are termed perceptions or ideas ; and 

 many of thefe motions during our waking hours are excited by 

 perpetual irritation, as thole of the organs of hearing and of 

 touch. The former by the conftant low indiitindl; noifes that 

 murmur around us, and the latter by the weight of our bodies 

 on the parts which fupport them 5 and by the unceafing varia- 

 tions of the heat, moiilure, and preiTure of the atmofphere ; 

 and thefe fenfual motions, ■ precifely as the mufcular one above 

 mentioned, obey their correfpondent irritations without our at- 

 tention cr confeioufnefs. 



5. Other daffes of our ideas are more frequently excited by 

 our fenfations of pleafure or pain, and others by volition : but 

 that thefe have all been originally excited by ftimuli from exter- 

 nal objects, and only vary in their combinations or feparations, 

 ha$ been fully evinced by Mr. Locke : and are by him termed 

 the ideas of perception in contradiftinction to thofe, which he 

 calls the ideas of reflection. A 



II. 1. Thefe mufcular motions, that are e::cited vy perpetual 

 ritation, are-ncverthelefs occafionaiiy excitable by the feniations 

 afure ox pain, or by volition ; as appears by the palpita- 

 tion 



