NUMBER OF PULSATIONS. 



blood, and the finger will feel it very distinctly moving 

 along. Find the artery which runs along the upper side 

 of the wrist and try it for yourself, there. 



Emily. Why this is the pulse which I have felt a 

 thousand times before. This phenomenon, then, which 

 has always appeared so mysterious to me, is nothing but 

 the successive waves of blood impinging against the 

 sides of the artery which is compressed by the finger. 

 As the whole mass of the blood is put in motion at each 

 contraction of the heart, the pulse must consequently be 

 felt at the same time over the whole body. This is a 

 new fact to me also. Pray tell me, Dr. B., what there 

 is about the pulse, which requires physicians to feel it, at 

 every visit they make their patients ? Much as I have 

 learnt about this subject, this still has an air of mystery 

 about it to me. 



Dr. B. The intimate relations and nice sympathies 

 that exist between the heart and every other organ, 'are 

 such, that the slightest derangement in any of them, 

 generally affects the action of the heart. Now the pulse 

 is the index of the power and number of the heart's con- 

 tractions ; of the quantity of blood thrown out ; and con- 

 sequently of the general condition of the system, relative 

 to health and disease. 



Emily. Ah, this clears up the mystery, and accounts 

 at the same time, I suppose, for the grave, wise-looking 

 face which the doctor puts on in the act of feeling the 

 pulse. You remarked just now, that the heart contracts 

 seventy-five times in a minute ; is this the exact 

 uurnber of the pulsations in a state of health ? 



Dr. B. This varies according to climate, age, sex, 

 health, &c. The common standard of an adult male 

 however, in good health, is about seventy ; but owing to 

 difference of temperament, habits of living, &c. it gener- 

 ally varies from sixty to eighty. Dr. Heberden mentions 

 a person whose pulse did not exceed sixteen ; and an 

 old writer speaks of one, whose pulse was not more than 

 ten beats in a minute. At birth, it is as many as one 



