OCCURRENCE OF ALUMINIUM SUCCINATE IN TREES. 117 
By no other arrangement has it been possible to devise a 
formula which agrees so closely with the analytical results. 
The formula for this deposit, is therefore, when pure, 
Al,(O,H,O,);A 1:03. 
In the less pure portion of the deposit the odour of butyric 
acid was somewhat strongly marked. In order to prove 
the presence, or otherwise, of this acid, 50 grams of the 
material was boiled for three hours in water, using a 
reflex condenser; the volatile acids were then distilled 
off and titrated with semi-normal soda. The amount of 
acid distilled equalled 0°1356% of the total succinate taken; 
the remainder in the flask was filtered, and the dark filtrate 
decolourised with animal charcoal; the filtrate on titration 
gave an additional 0°0574% of acid. On evaporation no 
succinic acid could be detected, so that the total acid 
extracted was 0°1937% calculated as butyric. 
A fresh quantity (about half a pound) of the material 
was then boiled and distilled as in the previous case, the 
distillate exactly neutralised with barium hydrate solution 
and the barium salt prepared in the usual way. This was 
ignited into barium sulphate with the following result :— 
0°4349 gram of the barium salt gave 0°3245 gram BaSO,= 
74°62. .The theoretical amount of BaSO, obtained from 
barium butyrate (Ba 2C,H,O.) is 74°917. Butyric acid is, 
therefore, the only volatile acid present in the deposit. 
Acetic acid is quite absent. Glycerol could not be detected 
so that the butyric acid is free. 
The succinic acid was prepared from the deposit in the 
same manner as previously recorded (loc. cit.), where is 
also given the analysis of the acid together with other 
characteristic reactions of the deposit. That the aluminium 
is largely present as an aluminate before deposition as a 
succinate, is suggested from the analyses of the ash of the 
