226 ON THE EFFECTS OF CERTAIN MENTAL 



awake us suddenly, and at once, it may be of such a kind, and just 

 such a strength, as to excite into their accustomed action the mus- 

 cles of those organs or members only which are more immediately 

 connected with the train of our ideas or incoherent thoughts, whilst 

 every other organ may remain torpid : and hence, the muscles 

 chiefly excited being those of speech, some persons talk ; or again, 

 those chiefly excited being those of locomotion, others walk in their 

 sleep, without being conscious, on their wakinij, of any such occur- 

 rence. Dreams of great power and vividness, which are terrible in 

 their character, and connected intimately in their scenery with our 

 own immediate destiny, are of so stimulating a character as to 

 rouse the whole faculties of the mind at once, and we are instantly 

 awoke. Of such a character were the dreams of Richard, on the eve 

 of the battle of Bosworth. These dreams are always dependent, 

 during a state of bodily health, upon intense mental anxiety, which, 

 if it permit sleep at all to take place, constantly produces dreams of 

 this kind, which as constantly interrupt it. The invasion of attacks 

 of acute disease are almost invariably marked with dreams of this 

 nature. 



Persons thus indisposed jump up suddenly in extreme terror ; 

 they are suddenly plunged into the ocean from high precipices, or 

 placed in situations of danger, from which they attempt to escape 

 by efibrts so violent that the dream is broken. So intense, and ap- 

 parently real, are the events and objects of these dreams, that the 

 personages or fiends of our visions remain, to the fancy, tenants of 

 our chamber for some time after waking, and it is with difficulty we 

 can imagine that these pictures, the children of a distempered fancy, 

 are not actual occurrences. Those dreams which produce sleep- 

 talking, are far inferior in the intensity of their character to those 

 which I have just described. Carrying forward the theory of 

 Hennings, which, with some trifling modifications, appears to me to 

 be the correct one, I should describe the Imagination of our dreams, 

 which cause sleep- talking, to be " ideas presented to the fancy, with 

 sufficient power to call into action the faculty of speech, the ideas 

 at the same time being of such a character as relate immediately 

 and directly to the exercise of this faculty. 



The modifications of sleep-talking are extremely variable, from 

 the use of a few incoherent expressions, to the distinct relation and 

 long description of scenes long past, or those which are then present 

 to the Imagination. These variations depend, doubtless, upon the 

 intensity of the dream, and upon the natural vigour of the Imagi- 

 nation thus excited. Children are particularly liable to sleep-talk- 



