Honey, its Origin and Adulteration. 91 



teeth with, which it is furnished. The honey gland also secretes 

 a peculiar acid to be mentioned presently. The bee retains the 

 fluid portion in the honey sac till the proper time should arrive 

 for deposition in the cell of the honeycomb. 



Before describing the floral fluid and its transition into 

 honey, it will perhaps be better to briefly describe the appear- 

 ance under the microscope of the different sugars that are 

 connected with the present subject. These are of three dis- 

 tinct kinds. 



Cane-sugar (sucrose) C 12 H n lw Grape-sugar (glucose) 

 C^H^O^HO, and Manna- sugar (mellitose) C^H^O^HO. 

 A fourth kind (fructose) is mentioned by some authors, but 

 requires more confirmation before it can be regarded as a 

 distinct sugar. 



Cane-sugar is the well-known crystalline substance usually 

 procured from the cane, but is-* found occurring in beetroot, 

 Indian corn, the lotus bean, and many other vegetables and 

 fruits. When pure, cane-sugar forms very fine oblique rhom- 

 boidal prisms, with dihedral summits. When crystallized on 

 slides for the microscope, it always has a tendency to form flat 

 bold crystals, which usually are so connected one with another 

 as to cause a mass, which, when large, is commonly called 

 sugar candy. Cane-sugar, when in contact with vegetable 

 acids, has always a strong disposition to change into the 

 second kind of sugar nientioned (grape-sugar) . So much is 

 this the case that the author has never yet found cane-sugar 

 in a natural state unaccompanied by traces of grape-sugar. 



Grape-sugar (glucose) is the sweet substance found in the 

 grape, dried raisins, diabetic urine, and wherever cane-sugar 

 has been formed. Besides differing with chemical re-agents, 

 grape-sugar has not the slightest resemblance under the micro- 

 scope to that from the cane. It crystallizes generally both 

 from water and alcohol in tufts, which consist of lainellge 

 radiating from a centre. The author has slides in which 

 glucose has crystallized in perfectly regular six-sided prisms, 

 but these instances are very rare. When a solution is hastily 

 evaporated, the crystals are beautifully dendritic. Glucose is 

 formed in plants by the addition of three equivalents of water 

 to one of sucrose, which change is caused by the continued 

 increase of warmth, action of acids, or a principle called dias- 

 tase, or all combined. For sugar being an organic body, like 

 all such in the living tissues is constantly undergoing changes. 



The third variety to be mentioned is manna or mushroom- 

 sugar (mellitose) . It is formed always during the fermentation 

 of cane, or grape-sugars. In old honey it exists in much 

 greater proportion than in new. It crystallizes in long four- 

 sided prisms. Mellitose differs from sucrose and glucose, in 



