336 Report of the Department of Chemistry of the 



or less acid salts. All the preparations described showed a strong 

 acid reaction on moist litmus paper which indicates free hydrogen 

 ions. 



In the estimation of carbon and hydrogen it was found impossible 

 to obtain a white ash by direct combustion even when heated for 

 a long time — the residue in the boat was invariably dark colored, 

 varying from light gray to quite dark. Plimmer .and Page 6 also 

 mention the difficulty of completely burning carbon in the presence 

 of phosphoric acid. The crystalline barium salts described in this 

 paper as well as those from cottonseed meal are particularly hard 

 to burn; on the other hand the amorphous salts burn more easily. 

 In the combustions of these salts we have always burned the sub- 

 stance twice; first in the regular manner; the dark-colored ash has 

 then been powdered in an agate mortar and mixed in the boat' with 

 chromic acid and burned a second time. In this second combustion 

 there has been observed an increase in weight in the carbon dioxide 

 varying from about 1 to 12 milligrams. Under these conditions it is 

 impossible to say whether a complete combustion has been affected 

 and it is not improbable that a small quantity of carbon has escaped 

 oxidation. We are inclined to believe that the percentage of carbon 

 as found is slightly low. As a check upon the carbon content found 

 in the barium salts we have always prepared and analyzed the free 

 acid in the combustion of which we have never experienced any 

 serious difficulty, the residue in the boat showing no trace of carbon. 



preparation of the free acid from the purified 

 crystalline barium salt. 



The acid was prepared from 4 grams of the barium salt in the 

 usual way. After drying in vacuum over sulphuric acid at room 

 temperature it formed a practically colorless, thick syrup. Its 

 reactions were identical with those which we reported for the acid 

 from cottonseed meal. 7 For analysis it was dried in vacuum over 

 phosphorus pentoxide at 78°. The preparation darkened per- 

 ceptibly in color but did not turn black. 



0.4936 gram subst. gave 0.1366 gram H 2 and 0.1960 gram C0 2 . 

 0.1645 gram subst. gave 0.1601 gram Mg->P 2 07. 

 Found: C = 10.82; H = 3.09; P = 27.12 per ct. 



preparation of inosite from the barium salt. 



The amorphous barium salt was used. Of the dry salt, 9.3 grams 

 were heated in a sealed tube with 25 c.c. 5 /n sulphuric acid to 150°- 

 160° for three hours. After cooling, the contents of the tube were 



6 Biochem. J own. 7:167, 1913. 



7 hoc. tit. 



