13 
No. 1. — Plaoue CuLTiKEs IX Albumin'-Gelatix Balls, 
A gelatin culture of plague was mixed up with al)out an ecpial (pian- 
tity of egg albumin and the mixture soaked on little balls of sterilized 
absorbent cotton about the size of a pea. These balls soon dried out 
and shrunk to hard, dry, flaky scales. 
One-half was exposed in a Petri dish in the 'cool chamber at 17^ to 
19^ C., and the other half in a dark room at 20° to 29° C. From time 
to time one of the dried balls was taken out and planted into bouillon. 
In case a growth appeared it was tested on media and animals. 
Plague cultures on gelatin-albumin balls. 
Time. * 
60 days 
75 days 
112 days 
Material e.xpended 
Cold chamber, 17° to 19° C. 
Dark room, 22° to 29° C. 
Growth 
Virulent for mice in 3 and 4 days , 
Growth 
Virulent for mouse in 5 days 
Growth 
Virulent for white rat in 3 days. . 
Virulent for mouse in 3 days 
Growth. 
Virulent for mice in 4 and iS days. 
Delayed growth. 
Virulent for mouse in 2 days. 
No growth. 
No. 2, — Plague Culture ox Albumin B.alls. 
Little lialls of sterilized absorbent cotton, about the size of a pea, 
were saturated with a d-days-old culture of plague mixed with some 
egg albumin, as in No. 1, but omitting the gelatin. 
Cold chamber, 
■ 17° to 19° C. 
Remarks. 
Dark room, 
22° to 29° C. 
Remarks. 
18 days 
+ 
19 days 
+ 
1 
22 day.s 
+ 
22 lays 
42 days 
+ 
42 days 
+ 
.59 days 
+ 
59 days 
- 
68 days 
+ 
68 days 
- 
78 days 
— 
Contaminated. 
78 days 
- 
Contaminated. 
89 days 
— 
Note. — Throughout this paper + means growth and — no growth. 
It is plain from these two series. Nos. 1 and 2, that plague will live 
a long time, even though dry, in an albuminous medium. In the one 
case it remained alive and virulent one hundred and twelve days, when 
the material was expended. 
The influence of a few degrees of tem})erature upon the organism 
is prettih’^ shown in these two series, for it lived thirty-seven days 
longer in one instance and twenty-six days longer in the other, 
although all the conditions were exactly the same, excepting a ditler- 
ence of 10° C. in the temperature. 
