and silicate of sodium gelatinises the solution. The gum of the — 
leopardwood is as good as commercial gum arabic for Yaa all 
purposes. | 
een es graven 
: or ee ne 18% 
Meonnig a ye ae oe a Prey | Oo 
ere 
100°0 
sep 2... Ue eek 
Wat fer ee ; 
Necoke Bee oh Ree ae ee ee 
1 
The precipitate in alcohol wanted less HCl for solution than in the gum of F. 
maculosa Py ts + ae 
Acacia dealbata, Link., Fl. Aust. ii. 415. A very good gum 
exudes ho this beautiful tree, which — its way to the European 
glass houses nearly one hundred years ag 
The watery solution reacts sour to gree is not precipitated by | 
sugar of lead, and ferric chloride does not stain it. It 1s 
gelatinised in concentrated solutions by ferric chloride, boned 
ae of soda. Alcohol ona epee the arabin without any addition 
id or alkali. HCl does sily dissolve the precipitate 12 
alcohol, but KOH dissolves it i in gs spirit, till it is thrown down 
again by ease of more alcohol. . 
The of the white wattle is the best substitute for arabic ee 
available tres native Queensland trees. : 
ANALYsIS— 
A ee ek. ee ee 
Arabin oe ae me p22: 
Albizzia Toona, Bail., Syn. Ql. Flora Ist Pa , i 1 
Cedar. This tree ee yields a cae ach contains arabin a m : 
in various proportions in different samples ] 
The arabin, which is soluble in aaa, is coagulated a 
ferric eee ‘eithout being stained by it. The pr niger 4 
dissolved by KOH. The arabin is not precipitated from the © 
solution by alcohol or alcohol on addition of HCl, but 1b} 
down uickly if KOH is added. It seems to be present ae alls : 
as a subanhydride, whieh must be converted in arabin first ] 
before it can be ae itated by alcohol. The alcohol redisso 
metarabin, Sailobis and onl; swelling u in water, 8 
disnlved by boiling, but goes into solution in co. old water, if val a 
amount of KOH or NaOH is added. Lead acetate makes a tur a 
in this solution, bo 
eee — metarabin is dissolved in diluted HCl om er 
anth, but is precipitated out of this solution bef 
on on i of KOH, whereas the acidulated tengee anth #0" 
thrown down by alcohol alone. 
ANALYSIS— 
Water... 18°6 
Arabin 56°4 
Metarabin 25°0 
