REPORT ON CHEMISTRY. 
511 
Of those which have been analysed, meconine and picro- 
toxin contain no azote, and therefore will most likely be found, 
on a more careful examination, to be destitute of basic proper¬ 
ties. Buchner has also found a base in columbo root, Quassia 
Simaruba, &c., to which he has given no name, and Pelletier 
has described two alkalies differing from cinchonin and quinin, 
found in the Carthagena and Cusco varieties of bark, and 
Miell one in white bark (China ovifolia ), which he has called 
blanquinine : over these, however, considerable obscurity still 
rests. 
Indifferent vegetable substances. —Becquerel* has pointed 
out some interesting distinctions between cane sugar, sugar of 
milk, and gum, which may probably be employed with advan¬ 
tage in distinguishing between them, or in detecting their 
presence in solution. Caustic potash, soda, or lime, is added 
to the solution, which is then digested on fresh precipitated 
hydrated oxide of copper in the cold. If gum be present, it is 
wholly precipitated; if saccharine matter, the copper is dissolved 
in whole or in part, and the solution is blue, yellow, or red, 
according to the quantity of sugar present. If the coloured so¬ 
lution be boiled, the copper remains in the state of protoxide ; if 
cane sugar be present—if it be sugar of milk—boiling reduces 
the copper to the metallic state . 
Manna sugar ( Mannite .)—Manna sugar has been analysed 
by Henry and Plisson and by Opperman, with the following 
results: 
Henry and Plisson = C = 38*77, H = 8*487,0 = 52*743 
Opperman . . . . = C = 40*32, H = 7*728,0 = 51*843 
Opperman’s result gives 4C + 9H + 4 0. 
Guerin has published an elaborate examination of the gums. 
He divides them into three classes : 1°. Arabine , of which gum 
arabic is the type, soluble in cold water; 2°. Bassorine, which 
swells into a jelly, but does not dissolve in water: Bassora 
gum is the type of this class; 3°. Cerasine, from the gum of 
the cherry-tree ( Cerasus), is also insoluble in cold, but soluble 
in boiling water, and when treated with nitric acid gives about 
one fourth less mucic acid than bassorine. 
Arabine , by his analysis, consists of carbon = 48*81, hydro¬ 
gen 6*2, oxygen 49*85, nitrogen 0*14=6 C + 5H-f50. Gum 
Senegal and the soluble parts of gum tragacanth and Bassora 
gum consist of arabine. 
Bassorine = carbon 37*28, hydrogen = 6*85, oxygen = 55*87 
= IOC -f 11 H + 11 O. 
Cerasine appears to be metamorphic arabine, for it has pre- 
* Ann. de Chrnie, lxvii. p. 15. 
