THE CEREBRUM, AND ITS FUNCTIONS. 803 



by certain narcotics, such as the Hachisch (a preparation of Cannabis Indica) 

 employed for this purpose in the East ; for the emotional condition of the in- 

 dividual under its influence is entirely under the control of external impressions; 

 so that those who give themselves up to the intoxication of the fantasia, take care 

 to withdraw themselves from everything which could give their delirium a 

 tendency to melancholy, or excite in them anything else than feelings of plea- 

 surable enjoyment. 1 The difference between the state of mind in ordinary Dream- 

 ing and that which is characteristic of Somnambulism is most remarkable in regard 

 to the rapidity and incoherence of the trains of thought in the former state, 

 as compared with the slowness and steadiness of the mental action usually ob- 

 served in the latter. It is true that in ordinary dreaming there is sometimes a 

 remarkable degree of consistency in the mental operations; for reasoning pro- 

 cesses may be carried on correctly, and even (through that freedom from dis- 

 traction which is consequent upon the suspension of external disturbing agen- 

 cies) with remarkable vigor and completeness, especially when they are the 

 continuation of a train of thought on which the mind had been previously en- 

 gaged during the waking hours; and music, poetry, &c., may be composed, 

 which, if afterwards remembered and written down, is found to be in accordance 

 with the rules of taste. Such, however, is not the usual character of the state 

 of dreaming ; for more commonly there is an entire want of any ostensible 

 coherence between the ideas which successively present themselves to the con- 

 sciousness ; and we are completely unaware of the incongruousness of the com- 

 binations which are thus formed. It has been well remarked that " nothing 

 surprises us in dreams." All probabilities of " time, place, and circumstance" 

 are violated ; the dead pass before us as if alive and well ; even the sages of 

 antiquity hold personal converse with us ; our friends upon the antipodes are 

 brought upon the scene, or we ourselves are conveyed thither, without the least 

 perception of the intervening distance ; and occurrences, such as in our waking 

 state would excite the strongest emotions, may be contemplated without the 

 slightest feeling of a painful or pleasurable nature. Facts and events long since 

 forgotten in the waking state, present themselves to the mind of the dreamer ; 

 and many instances have occurred, in which the subsequent retention of the 

 knowledge thus re-acquired has led to most important results. 2 But one of the 

 most remarkable of all the peculiarities in the state of dreaming, is the rapidity 

 with which trains of thought pass through the mind ; for a dream in which a 

 long series of events has seemed to occur, and a multitude of images has been 

 successively raised up, has been often certainly known to have occupied only a 

 few minutes, or even seconds, although whole years may seem to the dreamer 

 to have elapsed. There would not appear, in truth, to be any limit to the 

 amount of thought which may thus pass through the mind of the dreamer, in 

 an interval so brief as to be scarcely capable of measurement ; as is obvious 

 from the fact, that a dream involving a long succession of supposed events, has 

 often distinctly originated in a sound which has also awoke the sleeper, so that 

 the whole must have passed during the almost inappreciable period of transition 

 between the previous state of sleep and the full waking consciousness. 3 Hence 



1 See the Author's article "Sleep," in the "Cyclop, of Anat. and Phys.," vol. iv. pp. 

 688 690; and Moreau " Du Hachisch et de 1' Alienation Mentale, Etudes Psychologiques," 

 p. 67. 



2 See a number of such cases in Dr. Abercrombie's "Inquiries concerning the Intellec- 

 tual Powers." 



3 The only phase of the waking state, in which any such intensely rapid succession of 

 thoughts presents itself, is that which is now well attested as a frequent occurrence, under 

 circumstances in which there is imminent danger of death, especially by drowning ; the 

 whole previous life of the individual seeming to be presented instantaneously to his view, 

 with its every important incident vividly impressed on his consciousness, just as if all were 

 combined in a picture, the whole of which could be taken in at a glance. 



