12 Report from the Select Committee oppo'uited to consider 



atmosphere operating upoa each other : hence, at one time it 

 mav be particularly rife and violent, and at another time it may 

 not' appear at all. Malaria is the Italian word for a morbific 

 vapour arising from the earth, under the influerice of the sim's 

 heat, and of the electric interchange already alluded to ; it is 

 found every season all along the coasts of the Mediterranean, but 

 in u much greater degree in some places than in others : the es- 

 sential caus^e of the plague is double; first, the specific poison, 

 which is generated or multiplied in the bodies of those who la- 

 bour under the disease, without which it cannot exist ; and se- 

 condly, a state or condition of the atmosphere, which gives a 

 strong tendency to support the disease among the people at large; 

 it is virtually occasioned by a state of the atmosphere, and it is 

 communicated by the infection, either in clothes, wearing ap- 

 parel, or bed linen: animal matter, such as feathers, silk, or wool, 

 will preserve it much more readily than any thing else. The 

 contagious principle of the plague cannot be communicated the 

 same wav as that of small-pox, that is, by inoculation : if the 

 matter be introduced into the system, it does not entirely intro- 

 duce the plague, but it will introduce a disease which is nearly 

 similar. Has never understood that there is any difference between 

 that form of the plagsie which affects a person who has touched 

 another afflicted by it, and that which afflicts those who receive 

 it from the odour or vapour arising from a person who is so dis- 

 eased. The same remark mav be made with regard to the small- 

 pox ; the contagion of the small-pox is communicated in two 

 ways; one is bv the palpable mode of inoculation, or contact; 

 and the other is from the gas or vapour arising from the infected 

 person. It is the case with some diseases, that they cannot be 

 propagated by contact — Does not say it is always so with respect 

 to plague; but, for instance, measles, with all the experiments 

 that have been made on the subject, never have been palpably 

 communicated by inoculation. Each poison jnay be supposed to 

 have a peculiar mode of existence, and a peculiar mode of pro- 

 pagation. The same case occurs with regard to the liooping- 

 cough. The hooping-cough has never yet been communicated, 

 except by the breath, or by coming near the person infected with 

 it. Doubts whether a person removed from the place where he 

 was taken ill of a fever, either in England or Ireland, and carried 

 pven to a short distance, v.ould communicate it to anybody, even 

 under the verv worst state that he could have that fever. Gives 

 the following reason for thinking so : At one time it xvas a great 

 question, whether the yellow fever at Philadelphia was of domes- 

 tic origin, or originated from importation; and after we began 

 to take patients from Philadelphia to a place called Bush Hill, 



not 



