CtASS II. 1. 7. 2. OF SENSATION. 263 



the exuberance of it. Whence less sensorial power is exhausted 

 in delirium, than at other times, as well as in sleep; and hence in 

 fevers with great debility, it is perhaps, as well as the stupor, 

 rather a favourable circumstance; and when removed by nume- 

 rous blisters, the death of the patient often follows the recovery of 

 his understanding. See Class I. 2. 5. 6. and I. 2. 5. 10. 



Delirium in diseases from inirritability is sometimes preceded 

 by a propensity to surprise. See Class I. 1. 5. 12. 



M. M. Fomentations of the shaved head for an hour repeat- 

 edly. A blister on the head. Rising from bed. Wine and 

 opium, and sometimes venesection in small quantity by cupping, 

 if the strength of the arterial system will allow it. 



2. Delirium maniacale. Maniacal delirium. There is ano- 

 ther kind of delirium, described in Sect. XXXIII. 1. 4. which has 

 the increase of pleasurable or painful sensation for its cause, 

 without any diminution of the other sensorial powers; but as 

 this excites the patient to the exertion of voluntary actions, for 

 the purpose of obtaining the object of his pleasurable ideas, or 

 avoiding the object of his painful ones, such as perpetual prayer, 

 when it is of the religious kind; it belongs to the insanities de- 

 scribed in Class III. I. 2. 1. and is more properly termed hal- 

 lucinatio maniacafis. 



3. Delirium ebrietatis. The drunken dilirium is in nothing 

 different from the delirium attending fevers except in its cause, 

 as from alcohol, or other poisons. W T hen it is attended with an 

 apoplectic stupor, the pulse is generally low; and venesection 

 I believe sometimes destroys those, who would otherwise have 

 recovered in a few hours. 



M. M. Diluting liquids. An emetic. 



4. Somnium. Dreams constitute the most complete kind of 

 delirium. As in these no external irritations are attended to, 

 and the power of volition is entirely suspended; so that the 

 sensations of pleasure and pain, with their associations, alone ex- 

 cite the endless trains of our sleeping ideas; as explained in 

 Sect. XVIII. on sleep. 



5. Hallucinatio visds. Deception of sight. These visual hal- 

 lucinations are perpetual in our dreams; and sometimes pre- 

 cede general delirium in fevers; and sometimes belong to reverie, 

 and to insanity. See Class III. 1. 2. I. and 2. and must be 

 treated accordingly. 



Other kinds of visual hallucinations occur by moon-light; 

 when objects are not seen so distinctly as to produce the usual 

 ideas associated with them, but appear to u exactly as they are 

 seen. Thus the trunk of a tree appears a flat surface, instead of 



