Pulse-Kate. 127 



definition of normal body-temperature. 



From the foregoing results, it is obvious that no one point can be taken upon 

 the thermometer as indicating the average body-temperature. Certainly the 

 point at present in common use is too high, for the body-temperatures through- 

 out the day rarely average as high as 98.6 F. Furthermore, for purposes of 

 comparison it should be borne in mind that the results recorded in these three 

 tables indicate rectal temperatures, and there is conclusive evidence to show 

 that the temperature in the rectum may be a degree (Fahrenheit) or more 

 higher than that in the mouth. Since, therefore, most temperatures taken by 

 physicians are sublingual, it is obvious that the temperature of 98.6 F., as 

 commonly given on clinical thermometers, represents far too high a value for 

 the average normal body-temperature throughout the day. The body-tempera- 

 ture, furthermore, undergoes a regular rhythm during the day, the minimum 

 from 3 to 5 a. m., a marked morning rise at about 7, a slow, steady rise during 

 the daytime, reaching the highest point in the afternoon between 3 and 6. 

 There is then an evening fall, accompanied by a marked falling temperature 

 after going to bed, the minimum being reached again between 3 and 5 a. m. 

 A number of curves showing the normal fluctuations of the body-temperature 

 have been presented in a discussion elsewhere. 1 



With normal fluctuations in the daily temperature of every individual, and 

 with variations among different individuals, a point emphasized in a preceding 

 portion of this report is again brought to notice, namely, the importance of 

 knowing the normal physiological factors of each individual. If the body- 

 temperature of an individual is normally somewhat higher or lower than 98.6 

 F., it would be an observation of prime importance to the physician in treating 

 cases of illness in which temperatures ordinarily considered abnormal were 

 observed. While, therefore, temperatures several degrees above or below 98.6 F. 

 may fairly be taken as indicating a probable pathological condition, it must 

 not be forgotten that minor fluctuations above or below this point fluctua- 

 tions amounting to as much as 2 F. may well be within the range of physio- 

 logical limits and in no wise indicative of pathological conditions. 



Pulse-Rate. 



The pulse-rate is one of the most frequent observations made by the physician, 

 and yet as a rule observations of pulse-rate by physicians are made under such 

 circumstances as to exclude the records from contributions to our knowledge 

 of the normal pulse-rate. The psychical excitement incident to the physician's 

 visit, the possible slight apprehension on the part of the subject as to his con- 

 dition, and the degree of attention frequently manifested by patients when 

 the pulse-rate is being taken, all tend towards a pulse-rate considerably higher 

 than would be obtained if the subject were lying quietly without any extraneous 

 influences. 



1 Benedict and Snell, loc. cit. 



