122 



THE AMERICAN MONTHLY 



[July, 



dead birds beneath the skin. The 

 disorder is not accompanied by erup- 

 tions on the skin, but is characterized 

 by elevated temperature, dullness and 

 loss of appetite, often deep somno- 

 lence, by paleness of the fleshy parts 

 about the head, and by yellow colora- 

 tion of that part of the excrement 

 which is separated by the kidneys. 

 The most marked and constant lesion 

 is an intense congestion of the liver 

 with enlargement and softening; and 

 there are frequently other complica- 

 tions which, for the purposes of this 

 communication, it will be unneces- 

 sary for me to enumerate. My aim 

 is simply to establish the fact that this 



Fig. 34.— Micrococci of fowl cholera, from a stained 

 preparation of cultivated virus, X 1000. 



is a virulent internal disease, or in 

 other words a contagious fever. 



A little over two years ago M. 

 Pasteur presented his communica- 

 tion on this affection to the Acade- 

 my of Medicine,* and shortly after- 

 wards the writer began his investiga- 

 tions of it which were continued until 

 the present, and are not yet entirely 

 finished. The facts demonstrated by 

 these rese-arches, which bear upon the 



* L. Pasteur. Sur les maladies virulentes 

 et en particulier sur la maladie appelee vul- 

 gairement cholera des poules. — Bulletin de 

 l' Academic de MMecine, i88o, p. 12 j. 



etiology of the disease, are briefly 

 as follows : — 



I. The virulent liquids of the f owl's 

 body contain micrococci. — If we exam- 

 ine the blood or tissue-juices of a bird 

 nearly dead of cholera, or from one 

 that has recently died, we may find a 

 considerable number of granules hav- 

 ing the dumb-bell form, or some ap- 

 parently single globules, caused by 

 one part being directly beyond the 

 other in the line of vision. These 

 bodies are extremely small, less than 

 ^ffOTJT th of an inch in short diameter, 

 and perfectly motionless. If the mi- 

 croscopist relies upon this examina- 

 tion alone, however, it would not be 

 strange if he remained in doubt as to 

 the nature of the granules which he 

 has discovered. They might very 

 reasonably be considered as granular 

 fibrin, as the debris of broken down 

 cells, or as particles of uncertain na- 

 ture which have gained entrance from 

 the atmosphere. It will be found 

 difficult in many cases, if not gener- 

 ally, to obtain the bacterial reaction 

 to coloring matter by staining witli 

 anilin, violet, or other agents. 



Fortunately, the microscopist of to- 

 day has the means of accurately de- 

 termining the nature of such granules 

 — this is accomplished by their culti- 

 vation in suitable media. Pasteur 

 demonstrated that these granules 

 might be cultivated in a liquid ob- 

 tained by simmering the muscles of 

 fowls in water and afterwards filtering 

 to transparency and sterilizingby heat ; 

 this I have confirmed by long-con- 

 tinued and careful experiments. 



Can we be certain, however, that 

 the organisms which we are cultivat- 

 ing, really existed in the blood of the 

 fowl while circulating in the veins, or 

 may they not have gained entA.nce 

 from the air ? This objection is more 

 pertinent than many imagine, for not- 

 withstanding assertions, the proba- 

 bilities are that very few persons, 

 taking the world over, have made 

 pure cultivations from virulent 

 liquids. Klein believes that he has 

 done this with the virus of the dis- 



