ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
395 
may be carried on in any atmosphere. In fig. 51 is seen the apparatus 
arranged for cultivations in an atmosphere of C0 2 . 
Fig. 51. 
a , culture chamber, with hanging drop, in position on Microscope stage. 
6 6, brass clips on caoutchouc tubes attached to plugged tubes of culture 
chamber. 
c, washing apparatus, through which the gas generated in d passes before going 
into culture. 
e, vessel containing dilute HC1, for evolving C0 2 from the marble in d. 
Apparatus for setting Gelatin.* — Dr. L. Heydenreich describes an 
apparatus which he uses for setting gelatin or agar in flasks or test- 
tubes just removed from the sterilizer. It consists of a square tin box, 
30-40 cm. long, 20 cm. broad, and 20 cm. high. On the broad side are 
6 openings, placed one above another, and each with a diameter of about 
1 cm. A stream of water is passed into the box, and the water passes 
out through the lateral openings, any of which may, if necessary, be 
corked up. 
In this way gelatin or agar is rapidly set ; large flasks of hot gelatin 
* Zeitschr. f. wiss. Mikr., ix. (1893) pp. 309-11 (1 fig.). 
