CHEMICAL INVESTIGATION OF THE ROOTSTOCK OF VITIS OPACA. 5D 
When the mucilage was removed from the pulverised 
‘tuber,’ by treating with water at 50 —60°C., the remainder 
showed the raphides in an excellent manner; the mass 
appeared to be laced together by them, both in bundles 
and in single crystals. When thin slices were put into 
boiling water the substance did not dissolve or break up to 
any great extent, although it swelled considerably. A 
portion boiled continuously for four hours, became pinkish- 
brown in colour, but was then as hard and as uninviting 
as a food material as when first cut. The liquid was quite 
acid to test paper, and contained a reducing sugar. Thin 
pieces of the tuber were entirely soluble in concentrated 
sulphuric acid on gently warming, and without much 
darkening. On the addition of water and boiling some 
time, a considerable amount of reducing sugars had been 
formed. 
100 grams of the tuber were taken and which was in as 
fresh a state as possible; the outer portions were removed 
and the remainder cut into small pieces and ground intoa pulp 
in amortar. Water was added, and the whole stood over 
night, it was then heated at 50 - 60° C. for two hours. The 
liquid was quite mucilaginous and dropped from the rod in 
strings. It was squeezed through cloth, as it was impos- 
sible to filter it; a considerable amount had apparently 
gone into semi-solution. The residue was repeatedly 
heated at 50—60° C. ina fresh supply of water, squeezing 
through the cloth between each addition until 600 cc. had 
been obtained, and the extraction was thought to be 
complete. 60 cc. of this solution, when heated until 
constant at 100—105° C. contained 0°2870 gram total 
solids, equal to 2°8707. The amount of inorganic residue 
obtained from this on ignition was 0°820 gram equal to 
0°8207, This inorganic residue consisted of potassium and 
magnesium carbonates, a small amount of phosphates and 
