ABSENCE OF GUM AND PRESENCE OF A NEW DIGLUCOSIDE. 25 



kinos contain this glucoside are somewhat numerous ; it is 

 present in a maximum amount in such species as E. sicler- 

 oxylon, E. crebra, E. s icier ophloia and E. paniculata, or 

 those known as " Ironbarks " generally, and consequently 

 the kinos from these trees are practically insoluble in 

 alcohol, and for this and other reasons useless for tinctures; 

 but in some species in which it can be detected, the greater 

 portion of. the kino is soluble in alcohol, the glucoside not 

 being present in sufficient amount to render the kino in- 

 soluble. This again is characteristic of the chemical pro- 

 ducts of Eucalyptus species generally, each one having 

 diminishing constituents in some direction. 



Besides the insolubility in alcohol of this kino glucoside, 

 its peculiarity is shown in another direction, as the sugar 

 consists of a substance probably isomeric with melibiose — 

 that portion of Eucalyptus sugar, originally named eucalyn, 

 which is split off from levulose when melitose (raffinose) is 

 heated with dilute acid — -the only difference apparently 

 being that it is inactive to light. This affinity is shown by 

 the melting point of its osazone, and by the fact of this 

 being entirely soluble in hot water. The sugar is also slowly 

 but entirely fermented by yeast. According to E. Fisher, 

 the osazones of the simple glucoses are all insoluble in hot 

 water, the diglucoses, however, such as lactose, gave an 

 osazone soluble in hot water. Several different samples of 

 the osazone were obtained from the sugar, but in no 

 instance did the melting point exceed 178° O., the simple 

 glucoses thus appeared to be absent. O. Scheibler and H. 

 Mittelmeier in a paper on the inversion products of melitose, 1 

 show that the osazone of melibiose melts at 176 - 178° C, 

 and that it is soluble in hot water. They also show that 

 the complete inversion of melitose requires protracted 

 heating with sulphuric acid. 



1 Ber. 22, 1678 - 1686. 



