144 NATURE AND LIFE. 
a period of thirty-six hours, or about two days, during 
which the heat rises slowly to 41°. Toward the third day, 
this heat decreases, ready to reappear in exacerbations of 
from halfa degree to a degree, during three or seven days, 
at the end of which time the disorder has run its course. 
When the temperature gradually rises after the third day, 
a fatal result may be expected. Persistent heat in that 
case is the precursor of death. Eruptive fevers, like small- 
pox, scarlatina, and measles, present very important phe- 
nomena of heat. In these heat begins with the attack of 
the malady, and increases till the cutaneous eruption oc- 
curs. It keeps up at a maximum, which reaches 423° (in 
scarlatina), till the eruptionis complete; then it begins a 
declining course, variable with the phases of the eruption, 
which finishes either with scaling off as in scarlatina, or 
suppuration as in small-pox. And the temperature rises 
also in several surgical affections, bringing on a more or 
less inflamed and feverish condition. This is observed in 
wounds, and generally in every kind of traumatism, in te- 
tanus, aneurisms, etc. In the case of strangulated hernia 
and of burns, and in most cases of poisoning, on the other 
hand, it declines in a remarkable way. 
Very plainly this rising and falling of animal warmth in 
diseases can only be attributed to a corresponding state 
occurring in the energy of respiratory combustion. Wedo 
not yet exactly know the cause of these variations, that is, 
the mechanism by which the morbid influences stimulate or 
check the active production of heat. Some physicians see 
in it the effect of fermentations occasioned in the blood by 
certain microscopic beings, such as bacteria and vibriones, 
which may perhaps be supposed to be the fact in most 
febrile maladies. Others assume that, in local inflamma- 
tions, it is the inflamed organ which communicates heat to 
the whole body, as a furnace does in a confined space. To 
others the disturbance seems rather to bave a nervous 
