NATURAL DEPOSIT OF ALUMINIUM SUCCINATE IN TIMBER. 327 
almost exactly one hundred per cent. of alumina in the ignited 
residue, as the result of two determinations. The method adopted 
was to fuse the ignited residue with bisulphate of potassium until 
solution was effected, and to dissolve in water when cold; the 
solution was then acidified, the alumina precipitated in the usual 
manner, and ignited before the blowpipe until of constant weight. 
The base therefore consists of alumina. Iron is absent. 
Determination of the Acid. 
In the systematic search for the acid, experiment showed the 
absence of oxalic, tartaric, citric, malic and benzoic acids in the 
solution obtained by boiling the acid solution of the original 
material with carbonate of soda, filtering, and proceeding in the 
Usual manner; succinic acid alone being indicated, exclusive of 
a trace of acetic acid. The crystals obtained, as described below, 
answered all the tests for succinic acid. When the original 
substance is treated with a small quantity of nitric acid, it 
wholly dissolves, (the trace of organic matter other than the 
acid being destroyed); the solution is of a pale amber colour. 
On cooling, a mass of crystals separates out. These were filtered 
off, drained on a porous slab, and when dry, again heated with 
4 small quantity of nitric acid, the crystals obtained by cooling, 
filtering, and drying on a porous slab as before. These opera- 
tions were repeated three times, and at the conclusion the 
crystals were dissolved in water, a small quantity of animal 
charcoal added and filtered. The solution thus obtained was 
‘olourless ; this was evaporated in the air after concentration on 
a the water bath, white crystals being thus obtained. Although 
*pParently pure, yet, on ignition, a small residue was left, for it 
*Ppears to be exceedingly difficult to remove the whole of the 
lumina by solution and recrystallization of the acid. The 
“Ystals thus obtained were used to identify the acid, and for the 
{ualitative tests generally, but for material for combustion sub- 
limation between watch glasses was resorted to, the sublimate 
boiled With water for some time, concentrated, and allowed to 
“rystallize at the ordinary temperature. (Of course this — 
