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If the effervefcence had been carried 
almoft to its term, how could it begin 
afrefh, and go through the fame courfe, 
was to produce a fever in every refpeCt 
fimilar to that which preceded it ? 
This cannot be conceived. But we can 
conceive that the nervous fyftem gave rife to 
this reproduction, becaufe its morbid dif- 
pofition ftill exifted. Suppofe two men, 
juft recovered, one from a tertian and the 
other from a quartan ague, be expofed to 
the aCtion of intenfe cold, they will both 
of them be again taken ill, one of his ter¬ 
tian and the other of his quartan. Is it 
not evident that this relapfe is owing to 
the difpofition of the nervous fyftem ? 
Have we not many examples of this nature 
in nervous difeafes ? An impulfion is only 
wanted to produce their evolution. 
We ftiali here obferve, that fevers do 
nof always arife from miafma or conta¬ 
gion, but are frequently the confequence 
of a violent fhock, Thefe fevers have 
likewife 
