578 PRACTICE OF PHYSIC. 



in removing the delirium ; and I have known many instances of 

 persons who, when no light and noise were present, were affect- 

 ed with considerable delirium, but whom light, and an accus- 

 tomed voice speaking to them, brought back to their senses. 

 We consider the delirium as going to the highest degree 

 when the person is insensible to the most established asso- 

 ciations, as when he mistakes his own bed or nearest rela- 

 tions. It may be considered as a mark of the same when 

 the associations with respect to certain functions of the body, 

 which have immediately and steadily governed us, such as 

 the evacuations by stool and urine, are destroyed. We are par- 

 ticularly accustomed to the stimuli of these excretions, and to a 

 particular manner of exercising them ; and the greater part of 

 mankind is affected with a particular sense of cleanliness and 

 decorum with respect to them. When this is forgot, and the 

 faeces and urine voided insensibly, without taking notice of their 

 stimuli, this is a proof that the ordinary associations are lost, 

 and that a total obliteration of the memory has taken place. 

 Some ambiguity may indeed arise when we consider that this 

 may depend upon a paralytic state of the sphincter ani, or of the 

 muscular fibres in the neck of the bladder ; but with respect to 

 the sphincter ani, when the patient retains clysters perfectly 

 well, and when in voiding the faeces there are some marks of 

 effort, though no signal is given, we know that it is not owing 

 to a paralytic state of the parts, but merely to a state of the sen- 

 sorium which has obliterated the ordinary sense with respect to 

 the most common associations. But further, with respect to the 

 exercise of those functions that relate to the states of sleep and 

 waking, I have said (Physiology, CXXXI.) that sleep depends 

 upon a state of collapse more or less prevailing in the sensorium, 

 particularly with respect to the animal functions; every propensity 

 therefore to sleep is a mark of the diminished energy of the sys- 

 tem ; and drowsiness or coma indicate the same. Very often this 

 drowsiness is not succeeded by sleeping, or is without a propen- 

 sity to sleep, and the sleep is readily interrupted ; this is what 

 physicians call Coma vigil, or Typhomania, where nature pro- 

 ceeds the length of actual sleeping, but this is prevented by the 

 operation of some internal cause. Any degree of this typho- 

 mania may be considered as a mark of collapse, and when it 



