550 EXPERIMENTAL RESEARCHES WITH CHICKEN-CHOLERA MICROBES, 



Immediately after the inoculations, the rabbits were placed in 

 spacious clean hutches, separately, and food was given to them as 

 usual. They were also, all of them, sheltered from rain and sun 

 in like manner. 



The blood used for the inoculations was in each case derived 

 from the right atrium of the heart, near the vence cavce. The 

 quantity of blood derived was pretty uniformly the same each 

 time, viz., ^ ccm. {vide above). 



The time of inoculation of each new series lay within about 

 tivo hours from the moment the first of the preceding series died. 

 In cases where such rabbits were found dead, instead of being 

 observed to die, the body-temperature then taken yielded a 

 cue as to the approximate time when death occurred. 



The seat of inoculation was always a corresponding area on the 

 left side of the belly. After having shorn this area, a small fold 

 of the skin, where there was no blood-vessel running, was cut 

 across by means of a small pair of scissors. The wound thus 

 produced was made the entrance into a small subcutaneous 

 pouch, where the inoculation-material was easily and safely 

 deposited by means of the platinum-loop. 



The quantity of bacteria thus inoculated into the different 

 rabbits was, comparatively speaking, a limited one. The direct 

 microscopical examination of uniformly obtained and stained 

 samples of heart-blood of all the rabbits shortly after their death, 

 succeeded in showing only moderate numbers of individual bacteria. 



In four cases I have tried to determine approximately the number 

 administered, namely, in Inoculation Series x., xv., xix., and xx., 

 Nos. 19, 29, 37, and 39, Table III. About 10 ccm. of 6 per cent, rabbit- 

 broth-peptone-gelatine in a test-tube were liquefied, so as to have a 

 temperature of between 30° and 40^0., mixed with one platinum- 

 loop full (one-fifth of the quantity for inoculation) of the heart-blood, 

 and made to solidify, by means of iced water, in a homogeneous 

 layer along the inner walls of the test-tubes (Esmarch's method). 

 After having been in a thermostat at a suitable temperature for three 

 or four days, the coating of gelatine in the tubes presented innumer- 



