28 



BACTERIOLOGY. 



FIG. 12. ISRAEL'S CASE. 



(l) APPARATUS FOR PREPARATION OF POTATO- 

 CULTIVATIONS. 



Israel's Case. Sterilising instruments in the 



flame of a Bunsen burner is most destructive. It 



is better, there- 

 fore, to have a 

 sheet -iron case 

 (Fig. 12) to 

 contain potato- 

 knives, scalpels, 

 and other instru- 

 ments, and to 



sterilise them by placing the case in the hot-air 



steriliser for an hour at 150 C. The box can be 



opened at the side, and each instrument withdrawn 



with a pair of sterilised forceps when required for use. 

 Glass Dishes. Several shallow glass dishes 



are required for preparing damp chambers for 



potato cultivations 



(Fig. 13). The upper, 



being the larger, fits 



over the lower, and 



having no handle, 



admits of these damp 



chambers being 



placed, if necessary, 



in the incubator in tiers. The large size may also 



be used in the same way for plate cultivations. 

 Potato Knives. A common broad smooth - 



FIG. 13. 



DAMP-CHAMBER FOR POTATO- 

 CULTIVATIONS. 



