OF AUTS AND SCIENCES. 217 



The formation of carbonic dioxide was determined by a special 

 experiment, in which a portion of turmerol was oxidized out of 

 contact with the air ; upon acidifying with sulphuric acid a gas was 

 given off, which gave a copious white precipitate with lime-water. 



A. Study of the Distillate obtained from the Ether Extract with 



Steam. 



This consisted principally of water, with a few yellow or brown oil- 

 drops floating in it. It was extracted with ether, and the extract, 

 which had acid properties, boiled with water and calcic carbonate. The 

 solution of a calcium salt thus obtained, when allowed to evaporate 

 spontaneously, deposited spherical collections of white needles and a 

 yellow viscous substance somewhat more soluble than the crystals. 



The crystalline body proved to be the calcium salt of the new acid, 

 which we have called turmeric acid, after it had been purified by 

 repeated crystallization from water, which is tedious in the highest 

 degree, as all the solutions and evaporations have to be carried on at 

 ordinary temperatures ; in fact, it took us more than a year and a half 

 to prepare and purify the four or five grammes of this substance, 

 which have served for the present research. 



In regard to the nature of the viscous non-crystalline salt we cannot 

 speak with certainty, as we were unable to obtain it free from calcic 

 turmerate ; but we are of the opinion that it is a salt of an isomeric 

 acid, as an analysis of the salt, which had not been purified by crystal- 

 lization, gave 8.12 per cent of calcium instead of 8.93 calculated for 

 calcic turmerate, and the acid set free from the amorphous salt re- 

 mained liquid even at — 5°, while turmeric acid solidifies at ordinary 

 temperatures. 



The total yield of mixed calcium salts cannot be more than one or 

 two per cent of the turmerol oxidized, and the proportion of amor- 

 phous salt in this product is comparatively small. 



Turmeric Acid. CjiIIj^,. The calcium salt prepared and purified 

 as just described was treated with hydrochloric acid, and then ex- 

 tracted with ether. On evaporating off the ether, a yellowish oil was 

 left, which crystallized on standing, and gave the following analytical 

 results after being dried in vacuo: — 



I. 0.2198 gr. of substance gave 0.5954 gr. of carbonic dioxide and 

 0.1586 gr. of water. 

 XL 0.1320 gr. gave 0.3584 gr. of carbonic dioxide and 0.0960 gr. of 

 water. 



