Action of Tobacco Smoke 



355 



represents the height after the inhalation of three ^i^arettes, smoked during 

 thirty minutes. 



The first effect of the inhalation- of tobacco smoke Ox ^. heart is shown 

 in fig. 10. In this experiment the outflow of blood from, the heart was 



Fio. 9.— Rabbit. Uiethane. 



A shows normal blood-preBsiire, and B shows the fall after smoking three standard cigarettes. 

 Time, 30 seconds. 



measured by the cardiometer. It will be noticed that the heart filled with 

 blood, but that its systole was a little incomplete ; that is to say, it did 

 .lot empty itself quite as completely as it normally does : nevertheless, the 

 total output from the heart was increased. 



Cardiometer. 



P'lG. 10.— Cat, A-C-E : urethane. Artificial respiration. Cardiometer and blood-pressure. 

 Shows effect of inhaling smoke from a Manilla cigar with a plentiful supjily of air. Time, 30 seconds. 



From lialf to three-quarters of an hour after smoking, the blood-pressure 

 docs not rise on the administration of large doses of nicotine, and the vagi 

 arc found paralysed, although adrenaline causes its normal eff'ect. This 

 must mean that an excess of smoking produces paralysis of the autonomic 

 nerve cells in exactly the vsame way that nicotine does. 



VOL. 1., NO. 4, — 19( 



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