146 Composition of Honey. 
The first would be fully ripe, the last hardly the product we 
should like to market. 
The reducing sugars—so called because they can reduce 
the sulphate of copper when made strongly alkaline by the 
addition of caustic potash or soda—include all sugars but 
sucrose or cane sugar; and consist mainly of dextrose, 
which turns the ray of polarization to the right, and lev- 
ulose, which turns the ray to the left. Dextrose and 
levulose are both products of“various fruits, as well as 
honey. Dextrose and levulose are also called invert 
sugars; because, when cane sugar is heated with a mineral 
acid, like hydrochloric acid, it changes from cane sugar, 
which revolves the polarized ray to the right, to dextrose 
and lxvulose; but the latter is most effective, so now the 
ray turns to the left, hence the terms inversion, or invert 
sugar. Glucose is a term which refers to both dextrose 
and levulose, and is exactly synonymous with grape sugar. 
The amount of reducing sugars varies largely, as shown 
by numerous analyses, usually from sixty-five to seventy- 
five per cent; though a few analyses of what it would seem 
must have been pure honeys, have shown less than sixty 
per cent. But in such cases there was an excess of cane 
sugar. It seems not improbable that in such cases honey 
was gathered very rapidly and the bees not having far to 
fly did not fully digest the cane sugar of the nectar. Dr. 
J. Campbell Brown in a paper before the British Associa- 
tion, gave as an average of several analyses seventy-three 
per cent. of invert or reducing sugars; thirty-six and forty- 
five hundredths per cent. was levulose and thirty-six and. 
fifty-seven hundredths per cent. was dextrose. Almost 
always pure honey gives a left rotation of from two to 
twelve degrees. This wide variation is suggestive. Does 
it not show that very likely the honey from certain flowers, 
though pure, honey, may give a right handed rotation with 
a large angle because of a large amount of dextrose and 
little levulose. It occurs to me that these two uncertain 
factors, incomplete digestion and the possible variation in 
nectar, make determination by the analyst either by use of 
the polariscope or chemical reagents a matter of doubt. I 
speak with more confidence as our National Chemist pro- 
