SLEEP-WAKIN(i. 64-9 



following case also exhibited either rapid changes or an extraordi- 

 nary state of sensibility. Dr. Darwin relates the case of a young lady 

 about seventeen years of age, who, every day for five or six weeks, 

 had fits of violent convulsions, then retchings, next equally violent 

 hiccups, then tetanus, and at last sleep-waking, becoming insen- 

 sible, yet singing, quoting whole passages of poetry, and holding 

 conversations with imaginary persons, and coming to herself with 

 great surprise and fear, but with no recollection of what had hap- 

 pened. At length she could walk about the room in the fit without 

 running against the furniture, and evidently had some external 

 sense : for she took a cup of tea and expressed a fear that there was 

 poison in it ; and seemed to smell at a tuberose, and deliberated 

 about breaking the stem, because it would make her sister so 

 charmingly angry ; once heard a bell, was less melancholy when 

 the shutters were open, and impatient if a hand was held over 

 her eyes or her hands were held down, saying, " She could not 

 tell what to do, as she could neither see nor move." 



I conceive that those portions of the brain that are connected 

 with the nerves of the respective organs of sense may all be 

 completely torpid ; or only some of them ; or not completely 

 torpid ; or some in one degree of torpidity and others in another ; 

 and that they may appear torpid when they are not, or more torpid 

 than they are, from the attention being dull or directed to another 

 quarter : that one or more may become exquisitely sensible, while 

 the others are in various degrees of torpidity, and may fluctuate 

 rapidly between sensibility and insensibility or be peculiarly de- 

 ranged : that the partial intelligence of the brain may be of va- 

 rious degrees, and have various directions, and may act powerfully 

 with very little external sense : and that great variations in every 

 point may take place in the fits of the same individual, and even 

 in the same fit. If to these considerations we add the force 

 of habit, we shall explain all that is usually observed in sleep- 

 waking. Negretti laid the table, waited, and put the things away, by 

 habit ; and, in places to which he had been accustomed, showed no 

 confusion, but went through his business cleverly ; whereas, in a 

 place of which he had no distinct knowledge, he felt with his hands 

 all around, and showed much inaccuracy. He struck himself against 

 a wall severely, and against a door which they had intentionally 

 shut. Galen says that he himself walked about in his sleep a 

 whole night, till he awoke by striking against a stone that hap- 



