GRADUATED PIPETTES 



7 



2. Pipettes of i c.c. capacity graduated in o.oi c.c. 

 (Fig. 10, a). 



FIG. 8. Petri dish (a), and 

 capsules (b, c). 



FIG. 9. Plate box 

 with stirrup. 



3. Pipettes of 10 c.c. capacity graduated in o.i c.c. 

 (Fig. 10, b). 



These should be about 30 cm. in a b 



length (i and 2 of fairly narrow bore) , 

 graduated to the extreme point, and 

 having at least a 10 cm. length of clear 

 space between the first graduation and 

 the upper end ; the open mouth should be 

 plugged with cotton- wool. Each variety 

 should be sterilised and stored in a 

 separate cylindrical copper case some 

 36 by 6 cm., with "pull-off" lid, upon 

 which is stamped, in plain figures, the 

 capacity of the contained pipettes. 



The laboratory should also be pro- 

 vided with a complete set of " Standard " 

 graduated pipettes, each pipette in the 

 set being stamped and authenticated by 

 a certificate from one of the recognised Physical 

 Measurement Laboratories, such as Charlottenburg. 



FIG . i o. 



Measuring pi- 

 pettes, a and b. 



