BY R. GREIG SMITH. 549 



The residual fluid reserved for the extraction of acids was 

 evaporated to small bulk, acidified with sulphuric acid and 

 filtered. The residual chalk, with adhering salts and liquid 

 from the culture flask, was also treated with dilute sulphuric 

 acid until all the chalk had been decomposed and the suspen- 

 sion was strongly acid; it was then filtered. The two filtrates 

 were reserved for extraction with ether. 



The two residues of sulphate of barium and calcium were 

 dried in the air, then ground to a rough powder in a mortar, and 

 finally extracted with ether. After the evaporation of the ether, 

 the extracted acids were treated with hot water, when an oily 

 acid separated out. This was washed with water, dried, dissolved 

 in ether and filtered. After the ether had evaporated, the fatty 

 acid, which was solid at the ordinary temperature, was melted 

 and sucked into capillary tubes in which the acid crystallised in 

 clusters of silky needles. These melted at 42*5°, and apparently 

 consisted of lauric acid. 



The reserved filtrates were extracted with ether in Schoorl's 

 apparatus, and, after the ether had been distilled ofi", the residual 

 solution of the acids was added to the liquid from which the 

 lauric acid had been obtained. The volatile acids were driven 

 off in a current of steam. The proportion of these to the residual 

 or non- volatile acids was as 1:9-7, or roughly as 1:10. The 

 volatile acids consisted chiefly of butyric, with small quantities 

 of acetic and formic acids. The partial separation of the acetic 

 and butyric acids was effected by the treatment of the calcium 

 salts with strong alcohol as recommended by Schoorl,* and the 

 recognition was made by the odour of the acids and the ethyl 

 esters. The solution of the non-volatile acids was evaporated and 

 allowed to crystallise overnight, when prisms of succinic acid 

 separated out. These sublimed, gave a buff precipitate with 

 ferric chloride and ammonia, and melted at 180°. The method 

 of Schoorl was then followed, when a further separation of 

 succinate was effected. No other acids were obtained. 



* Schoorl, Jour. Soc. Chem. Inch, xix., 567. 

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