262 DISEASES CLASS IT. i. 7. i. 



ORDO I. 



Increafed Senfation. 

 GENUS VII. 



With increafed Aftion of the Organs ofSenfe. 

 SPECIES. 



I. Delirium febrile. Paraphrofyne. The ideas in delirium 

 confift of thofe excited by the fenfation of pleafure or pain, 

 which precedes them, and the trains of other ideas aflbciated 

 with thefe and not of thofe excited by external irritations or by 

 voluntary exertion. Hence the patients do not know the room 

 which they inhabit, or the people who furround them ; nor have 

 they any voluntary exertion, where the delirium is complete ; fo 

 that their efforts in walking about a room or rifing from their 

 bed are unfteady, and produced by their catenations with the im- 

 mediate affections of pleafure or pain. See Section XXXIII. i. 4. 



By the above circumftances it is diftinguimed from madnefs, 

 in which the patients well know the perfons of their acquaint- 

 ance, and the place where they are ; and perform all the volun- 

 tary actions with fteadinefs and determination. See Seel:. 

 XXXIV. 2. 2. 



Delirium is fometimes lefs complete, and then a new face 

 and louder voice ftimulate the patient to attend to them for a 

 few moments ; and then they relapfe again into perfect delirium. 

 At other times a delirium affects but one fenfe, and the perfon 

 thinks he fees things which do not exift ; and is at the fame 

 time fenfible to the queftions iwhich are alked him, and to the 

 tafte of the food which is offered to him. 



This partial delirium is termed a hallucination of the difor- 

 dered organ; and may probably arife from the origin of one 

 nerve of fenfe being more liable to inflammation than the others ; 

 that is, an exuberance of the fenforial power of fenfation may af- 

 fect it ; which is therefore thrown into action by {lighter fenfi- 

 tive catenations, without being obedient to external ftimulus, or 

 to the power of volition. 



The perpetual flow of ideas in delirium is owing to the fame 

 circumttance, as of thofe in our dreams ; namely, to the defect 

 or paralyfis of the voluntary power 5 as in hemiplegia, when one 

 fide of the body is paralytic, and thus expends lefs of the fenforial 

 power, the limbs on the other fide are in conltant motion from 



the 



