DISEASES OF SENSATION. SECT. XXXIII. i. 



ing lately been expofed to great excitement, is not 

 fo liable to be ftimulated into its healthy a&ion, 

 either by additional itimulus of food and medicines, 

 or by the accumulation of fenforial power during 

 its prefent torpor. In inflammatory fevers with de- 

 bility, as thofe termed putrid fevers, delirium is 

 fometimes, as well as flupor, rather a favourable 

 fign ; as lefs fenforial power is wafted during its 

 continuance (fee Clafs II. i. 6.8.), and the conititu- 

 tion not having been previoufly expofed to excefs 

 of Simulation, is more liable to be excited after 

 previous quiefcence. 



When the fum of general pleafurable fenfation 

 becomes too great, another kind of delirium fuper- 

 venes, and the ideas thus excited are miitaken for 

 the irritations of external objedls : fuch a delirium 

 is produced for a time by intoxicating drugs, as 

 fermented liquors, or opium; a permanent delirium 

 of this kind is fometimes induced by the pleafures 

 of inordinate vanity, or by the enthufiaflic hopes 

 of heaven. In thefe cafes the power of volition is 

 incapable of exertion, and in a great degree the 

 external fenfes become incapable of perceiving their 

 adapted ftimuli, becaufe the whole fenforial power 

 is employed or expended on the ideas excited by 

 pleasurable fenfation. 



This kind of delirium is diftinguifhed from that 

 which attends the fevers above mentioned from its not 

 being accompanied with general debility, but fimply 

 with excefs of pleafurabie fenfation ; and is there- 

 fore in forne meafure allied to madnsfs or to reve- 

 rie; it differs from the delirium of dreams, as in 

 this the power of volition is not totally fufpendid, 

 nor are the fenfes precluded from external ftimula- 

 tion ; there is therefore a degree of confiftency, in 

 this kind of delirium, and a degree of attention to 

 external objects, neither of which exifl in the deli- 

 rium of fevers or in dreams. 



