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other cases it is added in smaller quantities for the same purpose as in the case of honey. 

 To be able to determine the small quantity is the problem. 



In the first place, molasses or sirup from cane may show some polarization at 

 87 C. on the inverted solution. This polarization is generally to the right, though 

 there are cases where it was to the left. This dextrorotation may be due to a pre- 

 ponderance of dextrose in the reducing sugars of the sample due to the easy decompo- 

 sition of the levulose or may be due to the decomposition products formed when the 

 raw juice is being defecated with lime, or by chance it might come from a special fer- 

 mentation of the sample forming dextran. However; it can be said not to be due to 

 dextrins. The normal polarization of sirups and molasses has been studied in samples 

 of known purity from Louisiana and is given in the following table: 



Polarization of Louisiana molasses and sirup. 

 MOLASSES. 



SIRUP. 



It is noted that the average is +2.65, the minimum 0.00, and maximum +6.16. 

 The sample giving +6.16 was badly fermented, hence its high figure. There remain 

 about 100 samples to be examined, and when these are finished more definite figures 

 can be obtained. As far as the work has progressed, about +5.5 is the maximum for 

 the invert reading at 87 C. The iodin method spoken of in the honey work can be used 

 here, but the sample must receive some previous treatment before applying the test. 

 Ten grams of the sample can be diluted with a little water (if the sample be a molasses), 

 and shaken with 95 per cent alcohol, adding a little at a time with shaking. The pre- 

 cipitate settles on standing. When settled, pour off the alcohol, add a little water to 

 dissolve the precipitate, heating if necessary, and then reprecipitate with 95 per cent 

 alcohol. Repeat a number of times. If the solution of this material in water is still 

 dark in color, filter through charcoal, or, better, add a drop of hydrochloric acid and 



