PULSE. 



187 



existing between the pulses of the two sexes 

 in this respect, it is necessary to compare 

 equal things with equal. This is done in the 

 following table, where the pulse in the erect 

 posture, as deduced from 101 observations 

 on males of the average age of 27 years, and 

 74 observations on females of the average age 

 of 25^ years, is in either sex 86. 



So that for the same frequency of pulse the 

 effect of change of posture in the male is 

 more than twice as great as in the female. 

 The difference is still more strongly marked 

 in early youth. 



The instances in which one or more ex- 

 ceptions to general rules occurred are, as 

 already stated, more numerous in the female 

 than in the male, the exact proportions being 

 46 per cent, and 3-t per cent. The next 

 question connected with the effect of change 

 of posture on the pulse is, whether that effect 

 is the same at all ages ? The following table 

 answers this question for both sexes in the 

 negative. The averages are deduced from 30 

 observations at each age in the male, and 20 

 in the female. 



Hence, in the male, the difference above 

 20 between standing and lying is to the dif- 

 ference below 20 as 7 to 5 ; while, in the 

 female, the difference above 20 is to that 

 below 20 as nearly 3 to 1. The exceptions 

 to the general rule are also more frequent in 

 the young subject. 



Another question connected with the effect 

 of posture on the pulse requires to be exa- 

 mined, namely, does that effect vary with the 

 frequency of the pulse ? The following tables 

 will be found to furnish an answer in the 

 affirmative. The averages in the first table 

 are founded each on 15, and in the second 

 table on 10, observations. 



It will be seen that these tables concur in 

 establishing the general rule, that the effect of 

 change of posture increases with the frequency 

 of the pulse; in the male as the numbers 9, 15, 

 27, 39 j in the female as the numbers 8, 1 2, 18. 



Another fact bearing on the effect of posture 

 on the pulse, is established by the observa- 

 tions of the writer, in confirmation of less 

 accurate experiments previously made by Dr. 

 Knox and others, viz. that that effect is not 

 the same at all periods of the day. The only 

 satisfactory way of ascertaining this fact is by 

 contrasting the same frequency of the pulse 

 at different periods of the day. This was 

 done by the writer, who employed an average 

 of twenty observations on his own pulse, made 

 before noon, twenty between 12 and 5 P.M., 

 and twenty between 5i P. M. and midnight. 

 The greatest average difference between stand- 

 ing and lying (10 beats) occurred before noon, 

 the number in the afternoon being 8, and in 

 the evening 9. 



The cause of the different frequency of the 

 pulse in different postures of the body is a 

 question of some interest, in examining which 



