56 MEMORIAL SKETCH. 



psychology, through the study of abnormal mental con- 

 ditions, and the attention which he bestowed on mesmerism, 

 electro-biology, and other fashionable aberrations. In 

 January, 1847, he contributed to his Review an article on 

 Dr. Moreau's " Psychological Studies on Hachisch and on 

 Mental Derangement." The book made a deep impression 

 upon him, for it enabled him to grasp as he had never done 

 before the significance of the control exerted by the will in 

 a mind of healthy activity over its own trains of thought. 



One of the first appreciable effects of the hachisch (he wrote) 

 is the gradual weakening of that power of voluntarily controlling 

 and directing the thoughts, which is so characteristic of the 

 vigorous mind. The individual feels himself incapable of fixing 

 his attention upon any subject ; his thoughts being continually 

 drawn off by a succession of ideas which force themselves (as 

 it were) into his mind, without his being able in the least to 

 trace their origin. These speedily occupy his attention, and 

 present themselves in strange combinations, so as to produce 

 the most fantastic and impossible creations. By a strong effort 

 of the will, however, the original thread of the ideas may still 

 be recovered, and the interlopers may be driven away, their 

 remembrance, however, being preserved, like that of a dream 

 recalling events long since past. These lucid intervals, how- 

 ever, become of shorter duration, and can be less frequently 

 procured by a voluntary effort ; for the internal tempest becomes 

 more violent, the torrents of disconnected ideas are so powerful 

 as completely to arrest the attention, and the mind is gradually 

 withdrawn altogether from the contemplation of external realities, 

 being conscious only of its own internal workings. 



The phenomena of hypnotism also excited Dr. Car- 

 penter's interest, for they threw further light on the con- 

 ditions of the mind's activity when its volitional control 

 was suspended, and led him to reflect on the influence of 

 mental states on muscular feeling and exertion in the 

 presence of certain powerful ideas which the sensations 



