396 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
can be consolidated in 15-20 minutes. Care must be taken that the 
glass is not cracked by using tlie water too cold at first. 
Simple Method for Anaerobic Cultivations.* — Dr. 0. Roth has used 
for some time a glass vessel (fig. 52), having considerable resemblance 
in shape to a bed-pan, for cultivating micro-organisms anaerobically. 
The little tube g is N -shaped, and placed laterally, a position which 
prevents the gelatin from escaping when it is poured in during steriliza- 
tion. Both openings, W and W', are plugged with cotton-wool. The 
Fig. 52. 
former is attached to a wire corkscrew and the latter to a wire loop, so 
that the plugs can be pushed in or withdrawn with facility. 
When the necessary quantity of gelatin (8 cm.) has been poured in, 
discontinuously sterilized and inoculated, the gas is introduced through 
the tube g and passes out at the neck W. When all the air has been 
expelled and sufficient gas supplied, the neck is hermetically closed with 
melted paraffin, and the small tube g is similarly treated. 
Fig. 53. 
For water-examination, the angular entrance-tube g is replaced by a 
curved metal pipe introduced into the flask through the neck (fig. 53). 
The air is removed after the return to the laboratory. At e the pipe is 
expanded, and just below the swelling is fastened a piece of fine copper 
wire for the purpose of easily withdrawing the pipe. The gas is intro- 
duced through a caoutchouc tube fixed to the free end of R, and when 
the air has been quite replaced, the neck is plugged with paraffin, the 
caoutchouc tube being withdrawn while the paraffin is still hot. 
For cultivations in fluid media wherein a considerable amount of 
gas is disengaged, the following plan is suitable. 
A flask (fig. 54) of any convenient size is stopped with cotton- wool, 
through the middle of which passes a bent glass tube, near the other 
end of which is a bulb K, and the extremity is turned up at angle E. 
Centralbl. f. Bakteriol. u. Parasitenk., xiii. (1893) pp. 223-7 (3 figs.). 
