VARIOUS FORMS OF FEVER. 1055 



diseased condition before any formal attack of 

 fever, as proved by the experiments of Dr. Potter 

 before cited, and by those of Dr. Stevens, in the 

 marshy districts of New York. 



But it still remains a problem, why the duration 

 of the cold stage is inversely as that of the hot ? 

 This question has been the gordian knot of patho- 

 logy for above two thousand years. For the pur- 

 pose of placing the subject in as clear a light as 

 possible, I shall proceed to shew that in catarrh, 

 which may be regarded as the mildest form of 

 fever, the chill, or stage of depression, is longer 

 than in the quartan, and diminishes in duration 

 through the tertian and quotidian, until we arrive 

 at the continued form of the disease. 



In the first place, then, if an individual in 

 previous good health be exposed for some time to 

 a cold wind, damp night air, a shower of rain, or 

 a draft of air while sitting in a cold room, the 

 temperature of his body is gradually reduced 

 below the natural standard ; by which more or 

 less of a chill is produced, the action of the heart 

 diminished, perspiration checked, the various se- 

 cretions somewhat deranged, and the vital pro- 

 perties of the blood to a certain extent impaired. 

 But as the nutritive properties of the blood and 

 its power of maintaining the secretions are dimi- 

 nished in a very slight degree, it is often from 

 twelve to twenty-four, or even thirty-six hours, 

 before there is any perceptible fever, which goes 



