ILLUSTRATIONS. 143 



Africa, frambaesia, elephantiasis, variola vacc'ma, and hydrophobia : secondly, 

 such as are communicable by contact and the atnwsphtre ; as small pox, aaeaslf ?, 

 chicken pox, hooping cough, scarlatina, and cynanche maligna : thirdly, those 

 diseases generally communicable only in an impure air ; as plague, yellow fever, 

 typhus, in its various forms, and dysentery. 



The following extract is taken from the introductory part of dr. Kosack's let 

 ter: 



" The visiter or attendant contracts disease from one of in-o sonrus, either fror. 

 the filth of the sick room, or from a specific something issuing from the body of tlu- 

 sick, the consequence of the peculiar disease under which he labours. If a pf 

 son visiting another ill of the yellow fever, or plague, derives his disease from 

 the impure atmosphere, of the apartment, I ask, how it happens, that in all in- 

 stances he contracts the same disease with that of the person whom he visits . 

 why is his disorder not an intermittent, a. remittent, jail fe^er, or dystnttrt, 

 which are considered the usual produce of filth ? if he derives any thing *pe 

 cific from the sick, his disease is then assuredly not to be considered as occa- 

 sioned by the atmosphere, but depending on the peculiar condition (>f thejluidt, 

 or state of the system, induced by the action of a specific poison, in other word^ 

 it is to be considered a tontagivus disease. The distinction proposed by di 

 Bayley, inasmuch as it does not account for the communication of the peculiar 

 form of fever or disease which is thus propagated, I therefore consider to be insu: 

 ficient to account for the circumstances attending the communication of thcst- 

 diseases to which it is applied. That I may not be misunderstood, I will sup- 

 pose A to be ill of dysentery, a disease well known to be attended with a yectt - 

 liar train of symptoms; he is in a small confined apartment, his person is nep 

 lected, the atmosphere round him is rendered impure and offensive ; under these 

 circumstances B visits him, and a few days after is also taken sick with the 

 same disease, attended ia all respects with the same dangerous symptoms which 

 characterize the disorders of A. Dr. Bayley and those who adopt the doctrine 

 of infection as opposed to contagion, consider the disease of B to proceed fs-om the 

 imp'uritfis of the air of the chamber, and not from any thing peculiar emanating or 

 secreted from the body of \. But as we mar, nithout hazard, visit an equally 

 filthy chamber where C lies ill of choiera morbus, or D with a bruJstn limb, I 

 therefore ascribe the disease of B to something more than the impure air of 

 the chamber of A. I ascribe it to a peculiar xirus generated in his system b-y 

 the disease under which he labours, and communicated by his excretions to the 

 surrounding atmosphere, rendering it thus capable of producing the same disease 

 ID those who may be exposed to its influence." 



Eu"ope is already greati y indebted to that spirit of investigation which char- 

 pro'essors of tbe healiogartin this country ; a ^rit wjijrb has 1*2 



