CHLORAL AND OTHER NARCOTICS. 497 



the compound in its effect on the living body. Physiological re- 

 search has not yet reached, by vital analysis of action, a perfection of 

 knowledge on the subject now in hand. Such analysis is yet in its 

 early days. At the same time a general line of research has been made 

 out, and some results have been obtained which are of direct practical 

 value. Other facts have also been elicited which at first sight are sur- 

 prising, but which lose their singularity when they are correlated with 

 pure chemical physical demonstrations. I found, for example, in one 

 of my researches, that two chemical substances which are isomeric in 

 constitution that is to say, are composed of the same elementary 

 forms in the same proportions, but under different arrangement pro- 

 duce entirely different phenomena on the animal body. These isomeric 

 substances are the formiate of ethyl and the acetate of methyl. 



The agents used by man for his dreamy delights have thus a varied 

 influence on his nature. They are often rudely classed together as 

 luxuries ; but the luxuriousness which they foster may be fathoms wide 

 until they so far interfere with vital function as to reduce its activity 

 in a notable degree. Then there is something in common between 

 them, just as there is something in common when, being carried a 

 little further, they stop life altogether. 



For this is interesting respecting them, in the most potent sense. 

 They all kill when we let them have full play. This is obviously the 

 reason why they are called toxicants and intoxicants. They bear re- 

 semblance in action to the poison which once in the history of a past 

 civilization sped on the tip of an arrow from a discharged bow. 



The toxicants have variation of action in their early stages. Al- 

 cohols excite the mind and quicken the pulses before they depress. 

 Opium excites before it depresses. Tobacco does not in the strict 

 sense excite, but depresses and soothes from the first, so that there are 

 stages, which some persons always feel, when alcohol is antidotal to 

 tobacco. Among those persons who are total abstainers from alcohol 

 few are found who can bear tobacco in the most moderate use of it. 

 Under tobacco the heart seems rapidly to run down in power, and 

 alcohol is called for to whip it up again, also as it seems. The fact is, 

 that the heart is not the organ primarily concerned at all, but the 

 minute vessels at the termination of the arterial circuit. These minute 

 vessels are under a nervous influence by which the passage of blood 

 through them is regulated, and which influence is readily modified by 

 very refined causes acting through the organic or emotional nervous 

 centers. The effect of tobacco on these minute vessels, through the 

 nervous system, is to cause contraction of them as a primary fact, so 

 that the face of the person affected becomes pale and the surface of 

 the body cold, while the heart labors to force on the supply of blood 

 until its own vascular system comes under the influence : then the 

 stomach involuntarily contracts, and, after a time, the voluntary 

 vol. xv. 32 



