The Babcock Test. 47 



50. Acid measures. A 17.5 cc. glass cylinder (fig. 9) 

 for measuring the acid is generally included in the out- 

 fit, when a Babcock tester is bought. This cylinder an- 

 swers every purpose if only occasional tests are made; 

 the acid is poured into the cylinder from the acid bottle 

 as needed, or a quantity of acid sufficient for the num- 

 ber of test bottles to be whirled at a time, is poured 

 into a small glass beaker provided with a lip, or into a 

 small porcelain pitcher; these may be more easily 

 handled than the heavy acid bottle or jug, and the acid 

 measure is then filled from such a vessel. 



Where a considerable number of tests are made regu- 

 larly, the acid can be measured into the test bottles 

 faster and with less danger of spilling, by using some 

 one of the many devices proposed for this purpose. 

 There is some objection to nearly all of these appliances, 

 automatic pipettes, burettes, etc., although they will 

 often give good satisfaction for a time while new. Sul- 

 furic acid is very corrosive, and operators, as a rule, 

 take but poor care of such apparatus, so that it is a 

 very difficult matter to design a form which will re- 

 main in good working order for a long time. Auto- 

 matic pipettes attached to acid bottles or reservoirs, to 

 prove satisfactory, must be made entirely of glass, and 

 strong, of simple construction, tightly closed and 

 quickly operated. 



51. The Swedish acid bottle 1 answers these require- 

 ments better than any other device known to the writ- 

 ers at the present time. Its use is easily understood 

 (see fig. 18) ; it gives good satisfaction if the hole in 

 the glass stop-cock through which the acid passes has 



1 Now generally sold and kno\rn as the Combined Acid Bottle. 



