46 Testing Milk and Its Products. 



were popularly termed "fool pipettes." It is not known that 

 any of these pipettes have been sold of late years. 



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

 for measuring the acid is generally included in the outfit, 

 when a Babcock tester is bought. This cylinder answers 

 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 number of 

 test bottles to be whirled at a time, is poured into a small 

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

 lain pitcher; these may be more easily handled than the 

 heavy acid bottle, 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, auto- 

 matic pipettes, burettes, etc., although they will often 

 give good satisfaction for a time while new. Sulfuric 

 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 remain in a good work- 

 ing order for any length of time. Automatic pipettes 

 attached to acid bottles or reservoirs, to prove satisfac- 

 tory, must be made entirely of glass, and strong, of sim- 

 ple construction, tightly closed and quickly operated. 



51. The Swedish acid bottle answers these requirements 

 better than any other device known to the writers at the 

 present time. Its use is easily understood (see Fig. 19); 

 it gives good satisfaction if the hole in the glass stop 



