368 
SUMMARY OF CURRENT RESEARCHES RELATING TO 
tin or iron plate, and is let into a groove on the upper surface of the lid. 
This cap or cover is about 1 cm. high, 7*7 cm. long, and 6 cm. broad, 
and its object is to prevent evaporation of the fluid. 
Fig. 53. Fig. 54. 
Fig. 55. 
Fig. 56. 
Fig. 57. 
The slides are let into the fissures in the lid by placing a couple 
back to back, and fixing them together by means of a rubber ring. The 
ring not only holds them together but supports them on the lid. 
New Rapid Filter.* — Herr E. Funck has devised an apparatus for 
rapidly filtering nutrient media such as agar, gelatin, &c. The apparatus 
is made of copper, and consists of the double filter A (fig. 58), having a 
side tube E for filling the interspace A with glycerin or paraffin. 
The outflow tube is provided with a metal disk F, which serves to 
prevent dust and impurities from contaminating the filtered fluid, by 
closing G. The cover B of the hopper is fastened by means of screws 
C, and rendered air-tight through the intermediation of a rubber or 
asbestos band. The tube D serves to regulate the pressure of the steam 
* Centralbl. Bakt. u. Par., 2 te Abt., iv. (1898) pp. 200-1 (1 fig.). 
