52 THOMPSON YATES LABORATORIES REPORT 
The flask containing the mixture of earth, road sweepings, and tap water was 
allowed to stand on the laboratory bench for several days. Then 100 c.c. of the super- 
natant liquid were poured into another flask, and shaken up with about 2 grammes of 
fresh garden mould. This mixture was inoculated with I loopful of a culture of 
B. t. a., and the flask, unplugged, placed in a dark cupboard for two days at ordinary 
temperature. Plates were then made, about 0.25 c.c. being put into each plate, in 
I. B. s. 0.5 p.c, peptone 2 p.c, glucose 0.5 p.c, agar 1.5 p.c. 
II. B. s. 0.5 p.c, peptone 2 p.c, lactose, 0.5 p.c, agar 1.5 p.c 
III. B. s. 0.5 p.c, peptone 2 p.c, lactose 1 p.c, agar 1.5 p.c. 
I. 45 colonies on the plate. On the surface were 9, which were all 
transferred to broth, and subcultures made. 
Broth 
Milk 
Glucose Jelly 
Potato 
Indol 
Short bac. 
Actively motile 
General 
turbidity 
Acid, 
clotting 
Gas 
No liquefaction 
IVIoistj yellowish 
P.D. 
2. 
No change 
No gas 
No liquefaction 
' Invisible ' 
None 
3- 
" 
4; 
5* 
6. 
8. 
» 
Acid, 
clotting 
Gas 
No liquefaction 
Moist, grey. P.D. 
9- 
No change 
No gas 
No liquefaction 
N 
II. 
51 colonies, of which 7 
were on the surface. 
Broth 
Milk 
Glucose Jelly 
Potato 
Indol 
Short bac. 
Actively motile 
General 
turbidity 
No change 
No liquefaction 
No gas 
' Invisible ' 
? 
2. 
None 
3- 
Acid, 
clotting 
No liquefaction 
Gas 
Grey yellow, 
moist. P.D. 
4- 
No change 
No liquefaction 
No gas 
' Invisible ' 
5- 
6. 
7- 
? 
This plate was exposed to light for several days, when one of the surface colonies became yellow. 
