A STUDY IN MORBID AND NORMAL PHYSIOLOGY 



253 



experiment, the initation applied on the normal day for 3^ minutes reduced the 

 temperature 0°.8; on the fever day applied for 4 minutes i"t reduced it only 0^4. 

 lu the second experiment: nornml day No. 1, the current was applied 3.5 minutes, 

 the fall 0°.8; normal day No. 2, current (>.5 minutes, fall P. 6; fever day No. 1, 

 current 6.5 minutes, fall 1°; day No. 2, current 6.5 minutes, fall l°.l. In the last 

 experiment the time of application and the strength of current were the same 

 throughout; and the fall the first normal day was 2°, the second normal day 2°. 2, 

 the fever day 1°.6. 



These experiments certainly indicate that in the fevered rabhit peripheral irri- 

 tations have less effect in depressing the temperature than in the normal animal. 



The most thorough and seemingly reliable study of the temperature of the 

 healthy man, which has been to my knowledge made, is that of Prof Jurgensen, of 

 Kiel {Die Korperwdrme des Gcsunden Memchen, Leipsic, 1873). These researches 

 developed some very curious and interesting fticts, prominent among which were 

 the singular uniformity of the average bodily temperature under all sorts of cir- 

 cumstances, which profoundly influence the production of animal heat. The chief 

 of the disturbing influences tested were starvation, the use of cold baths, and 

 muscular exercise. The subject of the experiment went entirely without food for 

 62 hours (op. cit., p. 27), and the average temperature was during the two days 

 that of a normal day. Again, whdn cold baths of 25 minutes' duration each and 

 of a temperature varying from 9*^ to 11° C. (48° to 52° Y.) had been employed, 

 the diminution of temperature during the shivering fits which followed the baths 

 was so exactly compensated by the rise of temperature during the reaction that 

 the normal mean was strictly maintained. 



Jurgensen also found that there is a regular diurnal variation of temperature in 

 health precisely similar to that which is known to occur in fever. Thus it was 

 shown that the 24 hours is, so far as human temperature is concerned, divided into 

 a diurnal and a nocturnal period. Early in the morning (about 7 A. M. or a little 

 later) is the minimum of temperature ; from this to the maximum of temperature 

 in the evening (about 9 p. m.) constitutes one period, whilst the other is from the 

 maximum of the evening to the minimum of the morning. The last period, the 

 nocturnal, is the shorter, in the proportion of 100 to 136, and has an average 

 temperature of 36°.94 C. (98°.49 F.); whilst the mean of the diurnal cycle, from 

 about 7 A. M. to 9 p. m. is 37°.34 C. (99°.21 F.). 



Further, Prof. Jurgensen found that this rhythm of temperature was not affected 

 by starvation, cold baths, or other ordinary disturbing influences. 



Finally, he determined that in typical fever the daily cycle of temperature so 

 closely resembles that of health, that if each be represented by a curve one over 

 the other with the same abscissa, tliese curves will be parallel, and the only dif- 

 ference will be in tlie ordinates of the curves ; or in other words, in fever the 

 normal daily cvcle of temperature is preserved ; the average or mean simply being 

 shifted upwards. To use the language of Prof. Burdon Sanderson the " only 

 material difference between the two conditions is that in fever the norm is 3°. 26 i F. 

 higher. Whatever be the explanation of tliis, tiie fact comes out so clearly as the 

 result of observation, that it cannot be disputed." 



