CIRCULATION IN WARM-BLOODED ANIMALS. 135 



this length of time without disorder and without weari- 

 ness. To those who venture their lives in ships, it has 

 often been said, that there is only a plank between them 

 and destruction ; but in the body, and especially in the 

 arterial system, there is in many parts only a membrane, 

 a skin, a thread." 



402. Effects of Alcohol on the Circulation. " "W e 

 may suppose," says Dr. Barry, " that the more quick the 

 motion of the blood, the sooner old age will advance, or the 

 sooner the machine will wear out, and other circumstan- 

 ces being equal, that the number ef years which all men 

 may attain, will be in reciprocal ratio to the velocity of 

 their pulses. If we allow 70 years to be the age of man, 

 and sixty pulses in a minute for the common measure 

 of a temperate man, then we should have 2,209,032,000, 

 as the number of pulsations during his life. But if an- 

 other, by reason of intemperance, forces his blood into 

 motion at the rate of 75 pulses in a minute, then instead 

 of living three-score and ten years, he will run through 

 his whole number of pulsations in 56 years, thus cutting 

 short his days by the term of 14 years." Barry on Di- 

 gestion, London, 1759. 



403. This is certainly a sober consideration and ought 

 to be carefully weighed by those who urge along the 

 current of their blood by mixing it with alcohol, for as 

 we have already seen, this liquid is taken into the blood 

 in the same state in which it goes into the stomach, the 

 gastric liquid having no power to change it into nour- 

 ishment. The circulating fluid of him who drinks dis- 

 tilled spirits, though it be mixed with water, is therefore 

 a compound of blood and alcohol, which stimulating the 

 left ventricle, and making it contract with unwonted ra- 

 pidity, increases the number of pulsations, and exhaust- 

 ing the irritability, produces a weak and flabby condition 

 of the machinery, which finally refuses to perform its 

 functions, the miserable possessor sinks down and dies 

 before his time. 



What is said concerning the quickness of the pulse, and the age to 

 which a man may live? How much is it supposed that a person may 

 shorten his days, by quickening his pulse five times a minute by stimu- 

 lants ? Is alcohol digestible or not ? What is the composition of one's 

 blood who drinks spirits ? 



