INTRODUCTION. 



ground edges, as they are thus less likely to cut the 

 hand when being cleaned. 



3. Hollow slides and slides on to which glass cells 

 have been cemented. The cement ought not to be 

 destroyed or liquefied by heat. 



4. Cover-glasses. For ordinary use, 15 mm. in 

 diameter; for cover-glass cultures, however, they 

 should be 22 mm. in diameter ; round cover-glasses 

 are preferable, because their edges are not so likely 

 to catch in the cloth when they are being cleaned 

 as the square ones, and because they are more suitable 

 for permanent preparations. 



5. Watch-glasses of about 5 cm. in diameter, with 

 flat bottoms, for holding the staining fluids, etc. 

 Embryo cups, which consist of blocks of compressed 

 glass, in which depressions have been ground, are very 

 useful, only they are rather dear. 



6. Glass rods, thin and. thick. It is best to fuse the 

 platinum wire into the latter, as it is apt to become 

 loosened from the thin rod on cooling. 



7. Glass tubing of various sizes, for various pur- 

 poses; amongst others, for making cultivations of 

 anaerobic bacteria. 



8. Flasks. A few large ones for preparing nutrient 

 gelatine, etc., and smaller ones for cultivations. 



9. Small Brlenmeyer's flasks, very useful for bouillon 

 cultures, etc. 



10. Glass funnels ; large for filtering the nutrient 



