88 On the diff'erent Modes in ■which Denih 



Concussion of the brain, which may be considered as 

 the shtTlUest ile^ree of injiirv, occasions a state of nnnd re- 

 sembling intoxicciiion, and the resemblance in some in- 

 stances is so conipU'te, that the most accurate observer can- 

 not form a diasnosis, except from the hisiorv ot the case. 

 Pressure on the brain, which is a more severe injury thaa 

 concussion, produces loss of motion, insensibility, dilata- 

 tion of the pupils ; respiration becomes laboured and ster- 

 torous, is performed at !on^ intervals, and at last altogether 

 ceases, and the paiient dies. 



Jt forms an interesting matter of inquiry, whether spirits 

 when taken into the stomach produce their etlects on the 

 brain, by being absorbed into the circulation, or in conse- 

 quence of the syjnpathy that exist? between these organs 

 by means of the nerves. The following circumstances 

 lead mc to conclude that they act in the last of these two 

 ways. 



1. In experiments where animals have been killed by the 

 injection of spirits into the stomach, I have found this or- 

 gan to benr the marks of great iuHamniation, but never 

 found any preternatural appearances whatever in the brain. 

 2. Tlie tfiiicts of spirits taken into the stouiach in the last 

 experiment were so instantaneous, that it appears impossi- 

 ble that absorption should h.'.ve taken place before they were 

 produced 3. A person who is intoxicated, frequently be- 

 comes suddenly sober after vomiting. 4. In the experi- 

 ments which I have just related, I mixed tincture of rhu- 

 barb with the spirits, knowiny; from the experiments of 

 Mr. Home, and Mr. William Brandc, that this, when ab- 

 sorbed into the circulation, was readily separated from the 

 blood by the kidneys, and that very small quantities might 

 be detected in the urine by the addition of potash ; but, 

 though I never failed to find urine in the bladder, 1 never 

 detected rhubarb in it. 



The including the termination of the thoracic duct in a 

 ligature d(jes not prevent spirits, when taken into the sto- 

 mach, from producing iht-ir usual effects <m the nervous 

 system ; but subsequent observaiions, which Mr. Home has 

 already communicated tc) this Soc.etv, have shown that no 

 conclusion can be drawn from this experiment. 



That a poison may affect a distant organ, thr"U2h the 

 medium of tlie nerves, without entering the circulation, is 

 proved by the well-known circumstance of solution of the 

 extract of Ijc-L'adoniia, when applied to the tunica conjunc- 

 tiva of the eye, occasioning dilatation of the pupil of the 

 same eycj though no other part of the system is affected. 



It 



