2 GENERAL 1 MICROBIOLOGY 



solution may 'be Used Wtii dxhUzed, i.e., until dark green 

 in color. 



Heat will facilitate the action of the cleaning solu- 

 tion. 



Small amounts of organic matter adhering to glass- 

 ware are oxidized by this solution, but will not dis- 

 appear until removed by a suitable brush and cleaning 

 powder. * 



New Petri dishes and test tubes may conveniently be 



(a) 



(d) 



o 



FIG. 1. (a) Pipette, (6) Smith's Fermentation Tube, (c) Erlenmeyer 

 Flask, (d) Test Tube, (e) Roux Tube, (f) Petri Dish, (g) Roux 

 Flask. 



placed in a large glass jar, covered with cleaning solution 

 and allowed to stand over night. Heavy glass jars will 

 not stand heating in steam. New flasks may be partially 

 filled with cleaning solution and placed in steam for fifteen 

 minutes. 



Test Tubes. New test tubes should be filled with 

 cleaning solution, placed in a wire basket and heated for 



* Any inexpensive fine-grained cleaning powder as powdered pum- 

 ice stone, Bon Ami, etc., may be used. 



