CHEMICAL EXAMINATION OF RAW MATERIALS. 201 



lows : Fill- the vessel G to the uppermost mark with the fluid 

 whose content of alcohol is to be examined, then pour it into the 

 boiling flask K, rinse out G with water, and after pouring the 

 rinsing water into K put the apparatus together as shown in the 

 illustration. The contents of K are then heated to boiling by a 

 spirit or gas flame under the sheet-iron plate upon which K rests, 

 the flame being so regulated that the distillate flows in drops into 

 G. By too strong heating the contents of K might foam up and 

 pass into G, which would necessitate a repetition of the experi- 

 ment with another quantity of fluid. Wine, beer, and whiskey- 

 mashes frequently foam up on heating, which can, however, be 

 almost completely overcome by the addition of a small quantity 

 of tannin solution to the contents in K. 



The heating of the boiling flask is continued until sufficient 

 fluid is distilled over into G to fill it from J to J, this being a sure 

 indication of all the alcohol present in the fluid having passed 

 over. The flame is then removed, the vessel G filled to the 

 uppermost mark with distilled water, and the fluids intimately 

 mixed by shaking, the mouth of G being closed by the hand. 

 The fluid now contained in G consists only of water and 

 alcohol, and its volume is equal to that of the fluid originally 

 used. By testing the fluid with an alcoholometer the content 

 of alcohol found corresponds exactly to that possessed by the 

 fluid examined (alcoholic liquid, beer, fermented whiskey-mash, 

 etc.). 



Determination of the Alcohol by Means of the EbulUoscope. 



Many determinations of the content of alcohol in the alcoholic 

 fluid having to be made in a well-conducted vinegar factory, the 

 above-described distilling test is objectionable on account of the 

 time (about twenty minutes) required for its execution. Good 

 results are, however, obtained by the use of the ebullioscope, and 

 but a few minutes being required for the test with this apparatus 

 it can be frequently repeated, and thus even a more accurate idea 

 of the working of the generators obtained than is possible with a 

 single determination by the distilling test. The apparatus is very 

 simple, is easily managed, and allows of the direct reading off, 



