428 BACTERIA IN INFECTIOUS DISEASES. 



mals exhibit symptoms of sickness which are attributa- 

 ble to the influence of the yellow fever poison. 



" (Vide Barton, Cause and Prevention of Yellow 

 Fever, third edition, pp. 52-55 ; Feraud, de la fievre 

 jaune a la Martinique, p. 271 ; La Roche on Yellow 

 Fever, Vol. II., pp. 316-318 ; Blair, Yellow Fever Epi- 

 demic of British Guiana, third edition, p. 63.) 



"In view of these reports, the Commission was in- 

 structed as follows : ' It is obvious that if it be found 

 possible to produce some specific symptoms in some one 

 of the lower animals by exposing such animals in local- 

 ities known to be capable of producing the disease in 

 man, and thus to establish a physiological test of the 

 presence of the cause of the disease, we may even hope 

 to be able to determine the nature of and the natural 

 history of this cause, although prolonged investigation 

 may be necessary to effect it.' 



" The Commission has endeavored to carry out the 

 views of the Board of Health in this direction, but in 

 .consequence of the limited time at its disposal, the want 

 of a suitable place to keep the larger animals, and the 

 amount of work in other directions expected from it, it 

 has been found impossible to make an exhaustive exper- 

 imental investigation. Enough has been done, however, 

 to make it appear highly probable that the sickness and 

 mortality reported among animals during the prevalence 

 of yellow fever epidemics has been improperly ascribed 

 to the influence of the yellow fever poison. It is well 

 known that many of the inferior animals suffer from 

 epidemic diseases peculiar to their several species, and 

 this is especially the case in southern latitudes. We 

 know of no reason why such epidemics should not occur 

 coincidently with yellow fever in man, and it is not sur- 

 prising that many people unaccustomed to close observa- 

 tion should attribute the sickness in man and in the 



