5 oo THE POPULAR SCIENCE MONTHLY. 



There is a fact of singular interest in relation to the intoxicants I 

 have now described or named, and which before I proceed further 

 should be carefully noticed. The fact is this : That when the agents 

 produce a definite effect upon a living body, whether it be a human 

 body or the body of an animal that possesses desires and likings, there 

 is caused in that body, after a number of times of practice, a craving 

 or desire for the agent that produced the effect. In man this is so 

 marked that the most repugnant and painful of lessons connected with 

 the first subjection to the agent is soon forgotten in the acquired after- 

 sense of craving or desire. It really matters little which of the in- 

 toxicants it is that is learned to be craved for ; the craving for it will 

 continue when it has struck an abiding impression. We know this 

 fact well from the wide experience that has been gained of it in the 

 cases of alcohol, tobacco, opium, chloral, hasheesh, absinthe, and arsenic. 

 More incongruous things could scarcely be ; incongruous to the senses, 

 to the sensibilities, to the methods of taking, to the result of them ; 

 yet the craving for any one of them as it is may be established. The 

 devotee to one will laugh at the devotee to another ; each one will 

 consider the other almost insane, and yet each will follow his own 

 course. 



Still more curious is it that the substances craved for, which lie 

 quite outside the natural wants of healthy life, may be extended to any 

 number. There is in truth hardly a substance to which the craving 

 may not cling. The distinguished Dr. Huxham had under his observa- 

 tion a man who, after a little practice in the habit of taking it, had a 

 craving for the salt now called bicarbonate of ammonia. The man 

 chewed this salt and swallowed it in the same way as he might have 

 swallowed peppermint lozenges. The effect of the salt was to produce 

 extreme fluidity of the blood of the man, so that he became scorbutic, 

 and to cause loosening of his teeth. It also reduced his strength, and 

 even placed his life in jeopardy ; and yet his craving for the ammonia 

 remained unappeased until his danger was so great that the noxious 

 thing had to be withheld altogether. The great Sir Humphry Davy 

 gives another, and it may be still more remarkable, experience in rela- 

 tion to himself. When he was making his wonderful researches with 

 nitrous-oxide gas, he commenced, at first for the mere sake of experi- 

 ment, to inhale the gas in free quantities. By this process of inhala- 

 tion he obtained the most delicious of visions. Space seemed to him 

 illimitable, and time extended infinitely, so that coming out of one of 

 these trances he exclaimed: " Nothing exists but thoughts ; the universe 

 is composed of impressions, ideas, pleasures, and pains ! " In course of 

 time Davy, by the frequent repetition of the process of inhalation, be- 

 came so infatuated that he could not look at a gasholder, could not look 

 at a person breathing I am using his own description without ex- 

 periencing the urgent sense of desire to once more imbibe his favorite 

 gaseous nectar, and revel in his induced and artificial dreams. How 



