1 68 THE POPULAR SCIENCE MONTHLY. 



undue acceleration of the laboring forces of the heart. Under the stim- 

 ulus of tobacco the heart beats more quickly, as is evidenced by the 

 rising pulse. We have not the mass of detailed evidence as to this fact 

 which exists in relation to alcohol, but the experiments made by Dr. 

 Edward Smith, and related to the British Association in 1864, are full 

 of interest. " The experiments were made at 10 p. m., when the rate 

 of pulsation naturally declines (as he had proved by hourly experi- 

 ments published in his work on the ' Cyclical Changes of the Human 

 System'), and at least four hours after any fluid or solid food had been 

 taken. They were made in the sitting posture, after it had been main- 

 tained fifteen minutes, and with the most absolute quietude of body 

 and mind ; and thus all influences were eliminated but those due to the 

 tobacco. The rate of the pulsation was taken every minute for a period 

 beginning two or three minutes before the smoking began, and continu- 

 ing during twenty minutes, or until the pipe was exhausted. 

 The following are the chief results obtained : 



Experiment 1. 

 Pulsation before smoking was 74-J per minute. 

 Smoking 6 minutes 79, 77, 80, 78, 78, 77 per minute=78.1 average. 

 Smoking 7 minutes 83, 87, 88, 94, 98, 102, 102 per minute = 93.4 



average. 

 Smoking 8 minutes 105, 105, 104, 105, 105, 107, 107, 110 per minute 



= 106 average. 

 After smoking 11 minutes 112, 103, 107, 101, 101, 100, 100, 100, 100, 

 98, and 91. 

 There was thus a maximum increase of 37^ pulsations per minute. 



Experiment 2. 

 (Smoking through camphor julep in a hookah.) 

 Pulsation before smoking, 79 per minute. 

 Smoking 6 minutes 81, 81, 81, 83, 82, 82 per minute = 81.6 average. 

 Smoking 17 minutes 85, 89, 89, 93, 96, 90, 94, 94, 93, 92, 95, 95, 95 

 96, 94, 97, 93 = 93. 

 The maximum increase was 17-J pulsations per minute. 



Experiment 3. 

 (Smoking an empty pipe.) 

 Pulsation before smoking, 78 pulsations per minute. 

 Smoking 11 minutes 76, 78, 77, 76, 79, 79, 80, 80, 79, 78, and 79. 



There was no increase in the rate of pulsations from the effort of 

 smoking, or from its interference with the respiration. 



Experiment 4. 

 (To ascertain if, after smoking 6 minutes, during which the effect is 

 very small, and then ceasing smoking, any increase in the effect 

 would follow.) 



