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A MANUAL OF BACTERIOLOGY 



lateral branch of the filter flask is then connected with the 

 air-pump. On exhausting, the fluid passes through the 

 filter "candle" over into the filtering flask ; in which it 

 is collected. Before use the " candle " should be well 

 scrubbed and some water or J per cent, carbolic run 

 through to clean it, and the whole may be sterilised in the 



FIG. 5. Fleuss exhaust pump, arranged for filtration. 



steamer for an hour or two. After use the same process 

 should be repeated to cleanse it. 



Flasks, beakers, and test-tubes. A good supply of these 

 of various sizes is required : Erlenmeyer and ordinary 

 shapes, tall and short forms of beakers, etc. A few " yeast 

 flasks " are also useful (see Fig. 13, p. 75). Beakers and 

 flasks of " Jena " glass are to be preferred. Enamelled 

 iron ware, jugs, saucepans, mugs, etc., may replace glass 

 for many purposes. 



The most useful size of test-tube is 5" x f " ; a fow 

 larger sizes and " boiling tubes " should also be kept. 



Platinum needles (Fig. 6). Two or three platinum 

 needles are required. They consist of about two inches 



