NATURE OF MALARIA. 827 



in which respiration is seriously diminished, and 

 all the functions of life impaired, as shown by the 

 languor, drowsiness, headache, and even syncope, 

 induced in some cases. Nor can there be a 

 doubt, that such exposure for a sufficient length 

 of time, would greatly impair the vital properties 

 of the blood, and so far derange the nutritive 

 process as to induce all the symptoms of malarious 

 fever. 



I therefore appeal to the candour of all en- 

 lightened minds, whether it is not more in the 

 spirit of true science, to ascertain the influence of 

 carbonic acid, and of all other gaseous emanations 

 which are known to arise from the decomposition 

 of dead matter, than to seek for the nature of 

 malaria in some mysterious and hypothetical 

 condition of the atmosphere about which nothing 

 is known ? And whether vicissitudes of tempera- 

 ture do not constitute a still more important con- 

 dition of what is termed malaria, than even car- 

 bonic acid, or any other mephitic gas. For it is 

 certain, that in hot climates and seasons, exposure 

 to fatigue during the heat of the day, and to the 

 cool damp air of night, are by far the most com- 

 mon exciting causes of fever, the malignity of 

 which is in proportion to the elevation of tem- 

 perature where it prevails, ceteris paribus. 



