ZOOLOGY AND BOTANY, MICROSCOPY, ETC. 
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the bayonet-joint by which the lid is fixed on, and the spring at the 
bottom which prevents the lid from slipping. 
Sterilising Apparatus.* — The apparatus described by M. J. Hausser 
consists of a porcelain funnel with a perforated plate, and fitted into the 
mouth of a kind of separating funnel, which in its turn fits into the 
mouth of a flask connected with a filter-pump. All parts of the appa- 
ratus are heated to 125°, and boiling water and kieselguhr are run on to 
a double layer of filter-paper placed on the plate of the funnel. In this 
way a layer of moist kieselguhr, 0*5-1 mm. thick, is deposited. A layer 
of kieselguhr which does not allow the passage of air under a pressure 
of 1 kilo, acts as a perfect steriliser to any liquid filtered through it, 
whilst it permits the passage of 15-20 times as much liquid as does an 
equal surface of porous porcelain. 
Sterile Water Apparatus.! — Dr. L. Heydenreich describes an appa- 
ratus for making and keeping ready for use sterile water (fig. 173). It is 
Fig. 173. 
made of metal (copper or brass), its diameter is 18 cm., its height 20 cm., 
it holds about 5 litres, its inner surface is tinned, and it stands upon 
three legs. Close to the bottom is an outlet tube, 3 * 5-4 cm. long and 
3-4 mm. wide. This is provided with a tap, and its free end is expanded 
to grip a rubber tube. At the top is a short neck closed with a Hest’s 
stopper (see figs. 165-167). The apparatus is also provided with a 
water-gauge tube, and this is protected by a sliding shutter (not shown 
in figure). The apparatus is filled up to the neck with water, and 
then sterilised in a Papin’s digester for 20-30 minutes at 135° (two atmo- 
spheres). This apparatus will be found very convenient for bacterio- 
logical and other investigations. 
Funnel for Collecting the Sediment of Water intended for Bac- 
teriological Examination.^ — Dr. L. Heydenreich describes a funnel for 
obtaining the sediment of water for bacteriological examination. The 
* Bull. Soc. Ckim., xxi. (1899) pp. 250-3. See Journ. Cliem. Soc., 1899, Abat., ii. 
p. 569. t Zeitschr. f. wiss. Mikr., xvi. (1899) pp. 156-7 (2 figs.). 
X Tom. cit., pp. 178-9 (1 fig.). 
1899 2 y 
