18tJ 



PULSE. 



published 1796, investigated the subject more 

 carefully, and states, that "the result of 

 twenty-one accurate trials, made on different 

 days and at different times of the day, all 

 coincided to prove the greater frequency of 

 the pulse standing, than sitting or lying." 

 The greatest difference observed was 13 beats 

 in a minute, and the least difference one beat. 

 Each of these, however, occurred once only. 

 The average difference between the above 

 postures was about six and a third in a 

 minute." He adds, "The pulse in health is, 

 as far as I can find, the same in a sitting as in 

 a horizontal posture." Dr. Knox of Edin- 

 burgh*, however, has examined the effect of 

 posture on the pulse still more closely than 

 the authors just mentioned. In his first 

 memoir, published in 1815, he says, "During 

 the morning, the mere change of posture, 

 from the horizontal to the erect, shall increase 

 the pulse by about 15 or 20 beats. At mid- 

 day this increase shall be 10 ; and in the 

 evening 4, or 6." In his second essay, pub- 

 lished in 1837, Dr. Knox gives the results of 

 actual experiment. Nickf, in 1826, and Dr. 

 Graves J, in 1830, also examined the subject 

 experimentally. It is unnecessary to pursue 

 the history of this department of the pulse 

 into greater detail, as the fact that the pulse 

 is greatly influenced by posture is now familiar 

 to all medical men. The exact amount of the 

 change due to this cause will, perhaps, be best 

 displayed in the average results obtained by 

 the writer from a large number of facts ob- 

 served by himself. 



The following averages were derived from 

 observations on 100 healthy males of the 

 mean age of 27 years, in a state of rest, unex- 

 cited either by food or exercise, and, for the 

 most part, between the hours of 12 and 2 

 P.M. : 

 Standing, r i8'90 ; sitting, 70'05; lying, 66*62. || 



Difference between standing and sitting, 

 8*85 ; between sitting and lying, 3*43 ; and 

 between standing and lying, 12*28. 



These are the average results, from which, 

 however, the extremes are very widely sepa- 

 rated ; for the difference between standing and 

 sitting ranges from 26 to ; that between 

 sitting and lying, from 18 to ; and that be- 

 tween standing and lying, from 44 to 0. The 

 numbers in the observation, at the highest 

 extreme of the scale, were as follows : 



Age, 20. Standing, 98 ; sitting, 72 ; lying, 

 54 : differences, 26, 18, and 44. 



To the general rule that the pulse is more 

 frequent standing than sitting, sitting than 



Advancement of Science, Dublin Meeting, 1835, 

 p. 97. 



* Ed. Med. and Surg. Journal, vol. xi. and No. 

 131. 



f Op. cit. p. 41. 



$ Op. cit. p. 561. 



Guy's Hospital Reports, Nos. vi. and vii. 



jf It is a remarkable coincidence that Dr. Harden, 

 as the average of several experiments on his own 

 person, obtained the same numbers, viz. 80, 70, and 

 66. See American Journal of Med. Science, vol. v. 

 p. 342. 



lying, and, a fortiori, standing than lying, there 

 are several exceptions. Thus there were 

 5 instances in which there was no difference 

 between standing and sitting ; 19 in which 

 there was no difference between sitting and 

 lying ; and 2 in which the pulse had the 

 same frequency standing and lying. Again, 

 the pulse was more frequent sitting than 

 standing in 3 instances ; lying than sitting in 

 11 instances ; lying than standing in 5 in- 

 stances. The total number of instances, in 

 which exceptions to the general rule occurred, 

 was 34, or one-third of the whole. 



If we exclude all exceptions to the general 

 rule, and deduce an average from the 66 ob- 

 servations in which the pulse had what may 

 be termed its normal character, we obtain the 

 following numbers : 



Mean age, 27; standing, 81*03; sitting, 

 71-12; lying, 65*62: differences, 9*91, 5'50, 

 and 15*41. 



The female pulse presents some pecu- 

 liarities worthy of note, as will appear from 

 the following average results of 50 observa- 

 tions made under the same conditions as those 

 just recorded : 



Mean age, 27. Standing, 89*26; sitting, 

 81*98 ; lying, 80*24 : differences, 7*28, 1*74, 

 and 9*02. 



The extreme results, in the female as in the 

 male, are very wide of the averages ; for the 

 difference between standing and sitting ranged 

 from 24 to ; between sitting and lying, from 

 11 to ; and between standing and lying, 

 from 28 to 0. The exceptions to the general 

 rule are still more numerous in the female than 

 in the male, the total number of exceptions 

 being 60 per cent., and the number of observ- 

 ations in which exceptions occurred 46 per 

 cent. Of course 1 the rule here referred to is 

 the general rule established by observations 

 on the male pulse. 



If, then, we compare the effect of change of 

 posture on the male and female pulse, we 

 discover that the effect is greater, and the 

 exceptions to the rule less numerous, in the 

 male than in the female. This part of the 

 subject will repay a somewhat close examina- 

 tion. 



In the following table, the numbers of the 

 pulse, and the differences due to change of 

 posture, are given, in round numbers, the 

 averages being deduced from 66 observations 

 in the male, and 27 in the female, from which 

 all exceptions to the rule are excluded. The 

 mean age in both sexes is 27. 



From this table it appears, that though the 

 female pulse exceeds the male by 10 beats, or 

 th, the effect of a change of posture is con- 

 siderably less in the former than in the latter. 

 But, in order to determine the true relation 



