ON HONEY, ITS FORMATION AND CHANGES. 145 
Cheiranthus Cheiri, Lonicera Periclymenum , Trifolium pratense, and Rosa canina 
(Fig. 2). They are very difficult to separate, owing to the very rapid change 
into glucose by the chemical addition of a molecule of water. The angles are 
very decided, and measure 90° and 13425°. They are very beautiful objects 
for the polarizing microscope, and are most decidedly pure sucrose. 
The bee, then, led by instinct to the favourite plants, inserts its ligula into 
the corolla, and laps up the sacchiferous liquid, and passes it into the honey sac. 
The ligula is not, as was once supposed, a hollow tube, through which a liquid 
Fig. 2.— a, Sucrose from Polygonum Fagopyrum ; h, Cheiranthus Cheiri; c, Trifolium 
pratense ; d, Erica cinerea. Magnified 60 diain. 
may be sucked, but is a solid, flexile organ, covered with circlets of hairs. Like 
the palate of a mollusk, it is simply retracted into the mouth, and wiped, as it 
were, by the fauces. 
While retained in the honey-bag, it receives the addition of an acid which 
possesses all the reactions of formic acid. It is probably this that causes the 
peculiar tingling sensation in the throat that is frequently experienced when 
much honey is eaten. The formic acid may perhaps be the result of the decom¬ 
position of the sugar, thus— 
^ 12 ^ 22 On + 14 O = 10(HCHO 2 ) fl- 2 C0 2 -f- II 2 0. 
Cane sugar. Formic acid. 
On arriving at the hive, the bee deposits the contents of the honey-bag into 
the comb, where it remains till the stock is taken. 
At this stage, honey is a clear, thick, yellowish liquid, having a sp. g. 1‘423, 
and does not give a blue with tincture of iodine. 
After collection, this honey gradually thickens, and deposits crystals, becom¬ 
ing rather opaque. A bit, placed under the -microscope, will be seen to consist 
of a mass of regularly-formed crystals, as shown in Fig. 1, floating in a clear 
liquid, and interspersed with pollen-granules. These crystals are those of dextro- 
glucose; they are very thin and transparent, and the measurement of their 
VOL. X. L 
.3 
