456 THEORY OF FEVER, SUP. 1. 6. 



proceeding in our waking hours, and are catenated by their firft 

 link, or in fome fubfequent parts of the chain, with the ftimuii 

 or the influence of external things ; which we (hall here enu- 

 merate, as they contribute to the knowledge of fever. Of thefe 

 are the irritative ideas, or fenfual motions of the organs of fenfe, 

 and the mufcular motions aflbciated with them \ which, when 

 the chain is difturbed or interrupted, excite the fenforial power 

 of fenfation, and proceed in confufion. Thus if the irritative 

 ideas of fight are difturbed, the paralaftic motions of objects, 

 which in general are unperceived, becomes fenfible to us ; and 

 the locomotive mufcles aflbciated with them, which ought to 

 preferve the body erect, dagger from this decreafe or interrup- 

 tion of the fenforial power of afToeiation ; and vertigo is pro- 

 duced. 



When the irritative fenfual motions, or ideas, belonging to 

 One fenfe are ihcreafed or diminiihed, the irritative fenfual mo- 

 tioxis, or ideas, of the other fenfes are liable to become difturbed 

 by their general catenations ; whence occur noifes in the ears, 

 bad taftes in the mouth, bad odours, and numbnefs or tingling 

 of the limbs, as a greater or lefs number of fenfes are affected. 

 Thefe conftitute concomitant circles of difturbed irritative ideas ; 

 or make a part of the great circle of irritative ideas, or motions 

 of the organs of fenfe ; and when* thus difturbed occafion many 

 kinds of hallucination of our other fenfes, or attend on the ver- 

 tigo of vifion. 



2. Another great circle of irritative aflbciated motions con- 

 fifts of thofe of the alimentary canal ; which are catenated with 

 ftimuii or with influences external to the fyftem, but continue 

 to be exerted in our fleeping as well as in our waking hours. 

 When thefe aflbciations of motion are difturbed by the too great 

 or too fmall ftimulus of the food taken into the ftomach, or by 

 the too great excefs or deprivation of heat, or by indigestible 

 fubftances, or by torpor or orgafm occaGoned by their aflbcia- 

 tion with other parts, various difeafes are induced under the 

 names of apepfia, hypochondriafis/ hyfteria, diarrhoea, cholera, 

 ileus, nephritis, fever. 



3. A third circle of irritative aflbciate motions confifts of thofe 

 of the abforbent fyftem ; which may be divided into two, the 

 latteals, and the lymphatics. When the ftomach and inteftines 

 are recently filled with food and fluid, the lacteal fyftem is 

 ftimnhted into great action ; at the fame time the cellular, cuta- 

 neous, and pulmonary lymphatics act with lefs energy; becaufe 

 Icfs fluid is then wanted from thofe branches, and becauie more 

 fenforial power is expended by the lacteal branch. On this ac- 



; thefe tvv-o fyflemR of abforbents are liable to act by re- 



verfe 



