EXPERIMENTS WITH SUBJECT STANDING. 107 



making of a few adjustments prevented further records for nearly a 

 week. On this account, no pulse measurements were made for A. J. O. 

 and the records are incomplete for T. H. H. and W. K. As explained in 

 an earlier section (see p. 34), the difficulties experienced in the use of the 

 oscillograph were so many that the string galvanometer was substituted 

 in the early winter of 1915, and subsequently used for measuring the 

 pulse-rates of E. D. B., E. L. F., J. H. G., and H. M. S. The data 

 obtained are recorded and averaged in tables 3 to 7. (See pp. 43 to 55.) 

 It is a recognized fact that the pulse-rate is liable to sudden and un- 

 expected changes, even when the subject is at complete rest, 1 and that 

 the rate may be stimulated by thought or anticipation. 2 It is, there- 

 fore, with considerable hesitation that the term ' 'average standing 

 pulse-rate" is used. It is necessary, however, to have some basis to 

 work from and the term as here employed represents the general aver- 

 age of the records of each day for the individual subjects, regardless of 

 whether they include one or more periods. For instance, with W. K. 

 on March 16, the daily average of 81 is obtained from the record for the 

 first period only 3 and on June 4 the rate of 74 is from the third period 

 only, while that of 85 for June 1 is the average for four standing periods 

 on that day. (See table 5, p. 44.) It may be justly said that the rates 

 of 81 and 74 for March 16 and June 4 are given too much weight by this 

 method of averaging, but it has not seemed necessary to undertake a 

 more complicated method, as such a change would not affect materially 

 the general picture of the variations in pulse-rate. This is especially 

 true in view of the fact that on the days when both standing and walking 

 experiments were made, the standing rate for the day, and not the aver- 

 age rate for all the standing experiments with that subject, has been 

 used as the base-line in determining the change in the pulse-rate during 

 the subsequent periods of walking on that particular day. 



With these statements in mind, it is seen from table 4, page 44, that 

 T. H. H. had an average pulse-rate on March 19 of 100, with variations 

 on this date from 97 in the first period to 103 in the third. Three days 

 later (March 22) the average rate was 91, with a range from 87 in the 

 first period to 96 in the last period. The average for the two days was 

 96. On both days the pulse-rate increased during each succeeding 

 period, indicating that the effort of continuous standing increased the 

 work of the heart. 



The first day on which H. R. R. was a regular subject (March 20), 

 he had an average pulse-rate of 108. (See table 3.) While his pulse- 

 rate was probably stimulated on this day, owing to the novelty of the 



Benedict, Miles, Roth, and Smith, Carnegie Inst. Wash. Pub. No. 280, 1919, p. 389. 



2 Favill and White, Heart, 1917, 6, p. 175; also, West and Savage, Arch. Intern. Med., 1918, 

 22, p. 290. 



3 It should be emphasized that all counts were made photographically and several exposures 

 were secured during each period. The average for each period thus represents almost invariably 

 not less than three separate counts. 



