Part IV.] Puran Sing : Note on Burmese Varnish. 
297 
was added, refused to be precipitated by sulphuretted hydrogen. 
The solution of the gum was precipitated on the addition of am- 
luoniacal lead acetate solution. The gum, after its “ inversion ” 
had been effected by heating it for some time with dilute hydro- 
chloric acid (1 in 10), was found to reduce Fehling’s solution, which 
when boiled deposited cuproiis oxide (at first pale yellow and after- 
wards red). The substance before “ inversion ” had no such reduc- 
ing action. 
The dry material was redissolved, filtered, the filtrate was care- 
fully dried over the water bath to a constant weight, and the purified 
anhydrous gum so obtained was incinerated with the following 
result : — 
0 1305 gram gave 0'00T4 ash = 5'7 per cent. 
In Yoshida’s analysis of the gum from Japanese lacquer (which 
he proved to be identical in all essential characteristics with gum 
arabic), 0’52G7 gram of the gum gave 0'02GT gram ash^5T percent, 
(iuni arabic (as well as other natural gums) contain 12-17 per cent, 
of water, and afford on incineration 2-4 per cent, of ash. Making 
allowance for the complete absence of water in the specimen of gum 
under investigation, it will be seen that its composition closely 
agrees with that of gum arabic. The ash was further tested tor 
the presence of calcium, magnesium and postassium with affirmative 
results. 
From the jiroperties and reactions of the gum in question there 
can be no doubt that like the gum of Urushi, it, too, is identical in 
all essential characteristic with gum arabic. 
In order to ascertain the part played by this gum in the drying 
of thitsi, a drying experiment was made as in Yoshida’s investiga- 
tion of the Japanese lacquer, that is, a quantity of this gum and 
water was thoroughly incorporated with the isolated alcoholic ex- 
tract (now proved to be TTrushic acid), the proportions of the three 
substances being roughly the same as found in the specimens of 
thitsi e:\amined by the author (ride infra, p. 300). A glass plate 
was coated with this mixture and left to stand 48 hours exposed 
to the action of moist air the temperature of which ranged between 
22 and 25°C. (see below drying experiment Xo. 5. p. 303). It 
was observed that the mixture did not dry and remained of the same 
consistency as before, thus showing that the gum, though useful in 
