The highest member of the series of normal dibasic acids hitherto obtained by electrosynthesis is hexadecane dicarboxylic acid, HOOC.(CH2)16. COOH. In attempts to synthesise by this means dicarboxylic acids of still higher molecular weight, the following difficulties are encountered:—(1) The temperature of the liquid undergoing electrolysis must be kept above the melting point of the synthetic di-ester, in order that the latter may not solidify on the anode and prevent the passage of the current; (2) the alkali ethyl salts of the higher dibasic acids are of a soapy nature, and cannot readily be dealt with in concentrated solution. Two of the conditions favourable to electrosynthesis, high concentration of the electrolyte and low temperature, are thus unattainable.