586 
BEES AND BEE-KEEPING. 
the plane powerfully to the right. It is further 
detected by the copper test, over which it has no 
influence : while the sugars of diluted honey, if boiled 
with solution of sulphate of copper* made alkaline, 
reduce the copper salt to cuprous oxide, each molecule 
of sugar reducing five of copper, so that the exact 
amount of dextrose and levulose present in any volume 
of honey can be ascertained ; at the same time, the 
amount of cane sugar, if any, may be determined. 
If cane sugar be inverted (see page 378), by treat- 
ment with acids, e.g.^ sulphuric or tartaric, and then 
used as an adulterant, the resulting mixed dextrose 
and levulose, being identical with the sugars of honey, 
cannot be detected by polarisation. Their origin, 
however, betrays itself by the traces of acid which 
remain, and which give white, cloudy precipitates with 
barium or lead solutions. 
Sugar solutions of any kind, and however flavoured, 
if given in substitution of honey, are immediately 
detected by the microscope, as the counterfeit contains 
no pollen (see Fig. 127). Dilute the suspected material 
with about five times its weight of water, and stand 
twelve hours in a conical glass, when the heavier 
pollen will subside. Draw up the sediment by a 
pipette, or pour off the supernatant liquor, and 
examine with a low power. The amount of pollen 
discoverable in genuine honey is, however, extremely 
variable, depending not only upon the special bees 
which acted as collectors, but upon the flora and 
the character of weather at the time of gathering, 
* This is used in the form of “Fehling’s solution,” for which consult 
any recent work on practical chemistry. 
