CHEMICAL INVESTIGATION OF THE ROOTSTOCK OF VITIS OPACA. 57 
mination. As none of the exterior portion of tbe ‘tuber’ 
was present, and as the ignition was carried out in 
platinum, the alumina could not have been of accidental 
origin. The fully carbonated ash was treated with water 
and, when thoroughly extracted, 100 cc. of alcohol was 
added and the whole allowed to stand some time. The 
filtrate was evaporated down and made up to 100cc., it 
did not contain either lime, magnesia, sulphuric or 
phosphoric acids, but chlorine was present. The insoluble 
portion contained alumina, ime, magnesia, sulphuric acid, 
phosphoric acid, and carbon dioxide. 
The amount of alumina (Al,O3) found was 4°955% on the 
total ash, only the merest trace of iron was present. 
Almost the theoretical amount of the platinum salt of 
potassium was obtained and the K.O calculated from the 
total chlorides also agreed, thus indicating that sodium 
was absent. The percentage amount of CaO in the ash 
was 20°9; of P.O; 2°87; of K,O 15°74; and of MgO 5’d2. 
The nitrogen was determined by Kehldahl’s method 
giving 2°847% of nitrogen in the perfectly dried substance, 
or 0°138% on the ‘tuber.’ The amount of fats and allied 
substances soluble in ether was 0°788* on the perfectly dry 
material, or ‘038% of the tuber; a very small amount of a 
resin was present insoluble in petroleum ether, but this 
was more readily extracted by alcohol. 
Sugar—Only a small amount of substances was 
extracted by alcohol, and this after removal of the small 
amount of resin, was found to, be largely a crystallised 
sugar. Special efforts were taken to identify it, and it was 
determined to be dextrose on the following evidence. A 
large amount of the pulverised ‘tuber’ was treated with 90% 
alcohol for three days. ‘The filtrate, which was colourless, 
was evaporated to dryness and allowed to stand some time. 
It was then treated with ether until the resin was dissolved. 
