9 
Hankin (a) states that as far as his researches go they tend to show 
that the bubonic microbe, whether derived from cultures or the organs 
of deceased animals, and whether placed in cotton, or sheep’s wool, or 
gunny cloth, uniformly die out in six days. He states, however, that 
owing to the fact that epidemiological evidence tends to show that 
clothing may in rare cases convey the infection he is unwilling to draw 
any definite conclusions from his researches at present. 
The German Plague Commission (b) (Gaffky, Sticker, Pfeiffer, 
Dieudonn4) used the organism from agar-agar, and bouillon cultures ; 
also sputum from plague-pneumonia, peritoneal exudate from guinea 
pigs, etc. This infectious material was placed on various objects, as 
glass, silk threads, filter paper, fabrics, earth, etc., and permitted to 
dry. The plague-infected objects were placed in Petri dishes and xiut 
in a dark corner of the laboratory to dry out. As a rule, the infected 
pieces were turned over from time to time to hasten the drying. 
The temperature of the laboratory during these experiments was 
about 29° to 31° C. The objects were well protected from the light. 
Some were kept in an imjiro vised ice box, in which the temperature was 
about 22° 0. and the air saturated with moisture. The proof that the 
organism was still alive could, unfortunately, only be made by inocula- 
tion of mice and not by means of cultures. Small pieces of the infected 
objects were taken from time to time and placed under the skin of a 
mouse. The following are the results : 
Infected with pure culture. 
k 
Object. 
Temperature. 
Longest 
time in 
days the 
organism 
lived. 
30° to 32° C. 
3 
Glass in desiccator 
1 
Filter paper....'. 
3 
Filter paper in desiccator 
1 
Silk thread 
5 
Silk thread in desiccator 
do 
1 
Piece of silk 
6 
Piece of silk in desiccator 
do 
1 
Piece of wool 
6 
Piece of wool in desiccator 
2 
Large piece of linen 
Infected with plague organs. 
Glass 
Filter paper 
Silk thread 
Piece of wool 
Large piece of gauze, 
Large piece of linen. 
f 30° to 32° C. 
1 22° to 24° C. 
j 30° to 32° C. 
X 22° to 24° C. 
/ 30° to 32° C. 
I 22° to 24° C. 
! 30° t© 32° C. 
22° to 24° C. 
30° to 32° C. 
22° to 24° C, 
30° to 32° C. 
22° to 24° C. 
2 
2 
2 
2 
2 
2 
6 
6 
6 
6 
6 
8 
a The plague iu India, 1896, 1897, Yol. II, appendices I to T, page 10, et seq. 
h Deutsche Pestkommissiou. Kaiserliche Gesundheitsamt, Bd, 16. Berlin, 1899, 
page 274, et seq. 
