1873.] on the Temperature and Circulation. 375 



as showing how excessive expenditure of force may generate a condition 

 of high but transitory fever. 



My own results, so far as the temperature alone is concerned, are little 

 more than confirmatory of those of others ; but the records of the tracings, 

 and of the variations in the cardiac force which were noted at the same 

 time, may add something to their value. 



The observations detailed in the accompanying Tables were made on 

 thirteen males, in average good health, during winter or spring weather, 

 about the same hour, 8-10 p.m. The age of I. was 53-54, of II. 36, 

 of VIII. 38, of the others 16 to 26. All bore the exertion well, except 

 IV., who vomited, and was rather prostrate for a short time after. 

 The exercise consisted of a smart run for a mile or two. I have de- 

 scribed the sphygmometer with which I measured the force of the pulse 

 in the ' Medical Times and Gazette,' 1871, vol. ii. p. 183. After the run 

 the pulse-rate was generally first observed, then the force necessary to 

 compress the radial artery, then the tracing was taken, and lastly the 

 temperature. Wherever the pressure employed in taking the tracing is 

 not stated, it is to be understood that the same was employed before 

 and after the run. 



The result of the Sphygmometer observations was sufficiently constant 

 to indicate the effect generally produced, or tending to be produced, by 

 hard exercise. In eight out of the thirteen cases the artery was com- 

 pressed by a less force after than it had been before the exercise. The 

 difference in I. was represented by 100 grammes, in III. by 48, in IV. 

 by 112, in V. by 123 (about), in VII. by 56, in VIII. by 116, in X. by 

 376, in XI. by 100. These figures may be considered to represent the 

 diminution of the force exerted by the left ventricle. The amount of the 

 arterial contraction existing at the time of each observation is perhaps in 

 some measure concerned in the result, but is, I believe, a factor of far less 

 importance than the cardiac contraction. This opinion is borne out by 

 a reference to the tracings of VI., which indicate considerable arterial 

 constriction before the run, and but little after ; yet the sphygmometer 

 result is almost the same in both periods. In four instances, II., IX., 



XII. , XIII., the above relation was reversed ; the force of the cardiac 

 contraction appeared to be greater after than before the exercise. I 

 can be sure, I think, that this did not depend on erroneous observation. 

 The excess in II. was 56 grammes, in IX. nearly 200, in XII. 30, in 



XIII. 110 grammes. As these were vigorous individuals, it does not 

 seem improbable that the exercise, which lasted only some ten or fifteen 

 minutes, might excite the heart rather than exhaust it ; yet the tracings 

 of II. and IX. do not bear out this view. These four instances seem to 

 me very important, as demonstrating, what might have been suspected on 

 other grounds, how necessary it is to apply the dynamic test in judging 

 of the validity of the circulatory organs. It is not the amount of the 

 force put forth by the heart at a given moment, or the correctness of the 



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