Dr. R. D. Thomson, on the Mode of Testing Alcohol 95 



between the introduction of the spirit and death, it is rarely found that 

 the smell can be deteoted. Again, if the person should die under the 

 influence of spirituous liquors, and the stomach were not examined within 

 a limited period, the odour of alcohol might not be perceptible, since, as 

 absorption goes on for several hours after death, and as volatile fluids 

 appear to be peculiarly susceptible of rapid absorption, the whole of the 

 alcoholic fluid might be removed from the intestinal canal into the circu- 

 lation. It has been affirmed that alcohol has been detected in the brain 

 of gin drinkers; but as the mode of testing adopted was merely the 

 impression made upon the nerves of smell, we may perhaps be allowed to 

 doubt the accuracy of the experiment. It has even been affirmed, that 

 the gin obtained from the brain has been inflamed, and if this were correct, 

 we should then be entitled to quote nasal and ocular proofs of the presence 

 of alcohol in the brain, but as the gin of the shops is so weak, that in 

 its natural state it will scarcely burn — we may also be permitted to be 

 sceptical in reference to this second proof. These views do* not tend to 

 disprove the possibility of the presence of alcohol in the vessels of the 

 brain and other portions of the body ; because we know that hydrocyanic 

 acid passes to the very extremities of the body, and can be distinctly 

 detected by its odour, until it has either been removed from the system 

 by the combustion of respiration, or simply by exhalation from the lungs. 

 Now, alcohol and hydrocyanic acid are somewhat analogous, in a chemico- 

 physiological point of view, as they possess a powerfully sedative effect 

 upon the system, are exceedingly volatile, readily absorbable, and 

 require much oxygen to resolve them into simpler forms. For these 

 reasons, it appears highly probable that alcohol may be capable of detec- 

 tion in the vessels of the system, when it has been swallowed in large 

 quantities. The experiment, however, could only be made on the inferior 

 animals, and we should require some more definite test than the mere 

 smell of the alcohol. There are other circumstances, in a judicial point 

 of view, in which it may be of importance to detect minute quantities 

 of alcohol. For example, to distinguish small portions of the liquid 

 preparations of opium. In medicine there are used the solution of opium 

 in alcohol ; the solution of opium in wine ; the solution of opium in 

 alcohol, with benzoic acid and ammonia ; the solution of opium in vinegar ; 

 and lastly, the solution in water. When these preparations are entire, 

 there is not so much difficulty in their discrimination, but if they have been 

 exposed to the air, much of the alcohol escapes, and they may all become 

 analogous to a solution of opium in water. To distinguish those which 

 contain alcohol from those which do not, enables us to divide them into 

 two classes, and thus to simplify the inquiry. For these, and many other 

 cases where minute detection is necessary, I have been in the habit for 

 some years of employing a method which depends upon a well-known 

 fact, viz. the dehydrogenation of the alcohol by means of oxygen. For 

 this purpose, the fluid to be tested, if coloured, or a mixed one is to be 

 distilled in the water bath, until one-third of it passes over. Should the 

 Vol. II.— No. 2. 2 + 



