EFFECTS OF DRUGS ON WHITE MICE 125 



Cajfeine 



Caffeine was shown by Mosso ('93), Koch ('94), Hoch and 

 Kraepehn ('96), Schumburg ('99) and Rivers ('08) to increase the 

 capacity for work with the ergograph. From the results of these 

 experiments Rivers ('08) says: 



This stimulating action persists for a considerable time after the sub- 

 stance has been taken \vithout there being any evidence, with moderate 

 doses, of reaction leading to a diminished capacity for work, the sub- 

 stance thus really diminishing and not merely obscuring the effects of 

 fatigue. When taken in excess the stimulating action may be so transi- 

 tory, and followed by so great a decrease that it may legitimately be 

 spoken of as an accelerator of fatigue. 



IMETHODS 



This study was undertaken to find the effects of alcohol, nico- 

 tine and caffeine on the spontaneous activity of white mice when 

 kept under the influence of these drugs in moderate quantities 

 all the time. 



Sixteen male mice eight weeks old were used in the experiment. 

 They were all descendents of one pair of mice whose offspring had 

 been inbred for four generations. These mice belonged to the 

 fourth generation and came from four different lots, each lot being 

 the young of one male and several females. One mouse from 

 each lot was placed in each of the experimental lines. Thus 

 mice of the same sex, the same age, and very closely related were 

 the subjects of this investigation. 



Four lines were carried: one was given alcohol, a second nico- 

 tine, a third caffeine and a fourth was carried for controls. The 

 alcohol and nicotine were given in the same proportions as in 

 preceding experiments, as on these strengths the mice seemed to 

 keep in good health. The caffeine was given in a 1:300 solution. 



Each mouse in the alcohol line was given 35 per cent alcohol 

 to drink instead of water, and every other day, 3 cc. of 35 per 

 cent alcohol was added to its crackers and milk. 



Each mouse in the nicotine line received 1 : 1000 nicotine sul- 

 phate solution to drink instead of water, and had 3 cc. of 1 : 1000 

 nicotine sulphate added to its crackers and milk every other day. 



