534 EXPERIMENTAL RESEARCHES WITH CHICKEN-CHOLERA MICROBES, 



depth, height and width, respectively ; three were wooden-bottomed, 

 three wire-netting bottomed, the latter resting on sandy soil) were 

 stocked with three rabbits each ; two hutches (3' 3g" square, 2' high ; 

 one wooden-bottomed, the other wire-netting bottomed, placed as 

 before §) were stocked with six rabbits each ; here, as well as there, 

 always in the number of one infected to two uninfected specimens. 

 The experiment lasted seven days. Eight of the ten infected rabbits 

 promptly died from "chicken-cholera," as proved by the post-mortem 

 examination— they were removed from their hutches soon after death — 

 and by control-rabbits. All these had been fed on 2| ccm. of culture. 

 Of the remaining two, however, which had received only 1 ccm. 

 culture, one died (after more than 2^ days) from some indifferent 

 cause, and the other survived this time, while a control-rabbit [I ccm.) 

 succumbed to the disease. Of the twenty originally uninfected rabbits, 

 four contracted " chicken-cholera," and died in consequence, in the 

 smaller hutches, namely— t?iJO in one with bottom of rabbit-netting ; 

 one each in a wooden-bottomed and wire-netting bottomed hutch. I 

 need hardly say that these four rabbits, which perished in from about 

 two days and a half to four days seven hours after the beginning of the 

 experiment, had been together with rabbits which, after feeding on 

 2| ccm. culture, quickly succumbed, as mentioned above. 



I have also to record the death of t^m other (including five half- 

 grown) rabbits oub of the original twenty, within the seven days, but 

 I was unable to trace, as cause, "chicken-cholera." 



(b) On September lOth, 1888, two rabl-its were fed on green barley and 

 virulent culture (derived directly from the blood of one of the rabbits 

 dead from " chicken-cholera" by "contact," in one of the hutches of 

 the preceding experiment). One of them received 1 ccm.; the other, 

 which was the surviving one from the former experiment after feeding 

 of 1 ccm., was given 2 ccm. this time. They were p'aced in two of the 

 smaller hutches (see above), one having a bottom of wood, the other 

 one of rabbit-proof netting (as before), with one full-grown and one 

 half -grown rabbit for each. The two infected rabbits died speedily 

 from " chicken-cholera " (they were removed from their hutches soon 

 after death) ; of the four uninfected rabbits, the two half-grown and 

 one full-grown died within the first three days ; the result of post- 

 mortem examination was each time negative as regards " chicken- 

 cholera." The other full-grown specimen was still alive after seven 

 days. 



§ All the eight hutches were placed in the large wire-gauze enclosure on the Island. Six 

 of theua (the small-sized) were so placed as to prevent the sun completelj' from shining 

 into them ; the inside of the two larger ones was only to a slight extent accessible to 

 the sun. 



