806 NUTRITION AND HEAT REGULATION. 



strated upon man that there is no need for experimental investi- 

 gations to establish this fact. Pathological examination of the 

 tissues in the case of confirmed drunkards has demonstrated the 

 existence of definite lesions in many of the organs, stomach, 

 liver, heart, nervous system, and have shown that under these 

 conditions it acts as a tissue poison.* This result is exhibited 

 not only in cases of chronic alcoholism in which these lesions 

 have developed gradually, but also in cases of acute alcoholism 

 resulting from excessive doses. On the other hand, it is known 

 that many individuals use alcohol in moderate doses throughout 

 life with no noticeable evil result, but, on the contrary, with possible 

 benefit, particularly in advanced life. The matter of practical 

 importance and interest is to determine the physiological role of 

 moderate doses of alcohol. Does it serve a useful purpose, acting 

 as a food or stimulant, or is it a poison in all doses to a greater or 

 less extent ? The literature upon the subject is very large and 

 in many respects conflicting. Only a brief summary can be 

 attempted here. Regarding its stimulating action the general 

 experience of mankind attributes a result of this kind to its use 

 in small quantities. It confers a sense of well-being and an in- 

 crease in mental and muscular activity, although these good effects 

 may be quickly overstepped by too great a dose. Specific researches 

 have been made to show that the alcohol may decrease the reaction 

 time and increase the rapidity and amount of the muscular 

 contractions. On the heart and blood-vessels alcohol in small 

 quantities appears to have no positive effect of a stimulating 

 character. It is known that even in small doses it causes a dilata- 

 tion of the skin vessels, giving a feeling of warmth and leading to 

 increased loss of heat ; but whether this effect is due to a stimula- 

 tion of the vasodilator centers or, as seems more probable, to a 

 narcotic or depressing action upon the vasoconstrictor centers has 

 not been definitely demonstrated. Some observers obtain results 

 which indicate that alcohol decreases the efficiency of the neuro- 

 muscular apparatus and acts in all doses as a sedative or paralyzant 

 rather than f as a stimulant. It has been suggested that as regards 

 the higher nerve centers its apparent stimulating effect may be due 

 in reality to a paralysis of inhibitory centers, thus removing control 

 and restraint and leading to freer mental action. The experience 

 of explorers bears out the general view that under conditions of 

 stress and excitement alcohol is of little value as a stimulant. What- 

 ever action it has in this direction is temporary. After the day's 



* See Welch, "The Pathological Effects of Alcohol," in "Physiological 

 Aspects of the Liquor Problem," vol. ii, 1903. 



t For literature and discussion see Abel, " The Pharmacological Action of 

 Alcohol," in "Physiological Aspects of the Liquor Problem," vol. ii, 1903. 



