Synthesis of Succinic Acid.—Potassium-ethyl malonate is easily prepared according to the directions of Freund (Berichte der deut chem. Gesellschaft, xvii. 780).

The conditions most favourable for the electrolysis were found to be as follows :—A large platinum crucible formed the cathode, while a spiral of stout platinum wire was used as the anode. The source of electricity was a battery of accumulators, and the current was so regulated that while passing through the solution it had an electromotive force of 12 volts and a strength of not more than 5 ampères. Under these circumstances the heat developed in the solution could be easily conducted away by a stream of cold water flowing round the platinum crucible.