New York Agricultural Experiment Station. 369 



dilute hydrochloric acid by nearly neutralizing with ammonia and 

 acidifying with acetic acid. After purifying in this way 0.0826 

 gram of the substance was burned to constant weight in a platinum 

 crucible. The calcium oxide remaining weighed 0.0310 grams. 

 Calculated for the above quantity of CaC 2 4 +H 2 = 0.0316 gram 

 CaO. 



The calcium oxide was dissolved in dilute nitric acid and tested 

 with ammonium molybdate. A faint precipitate separated showing 

 that some phosphorus remained. There appears, however, to be 

 no doubt that the substance was a nearly pure calcium oxalate. 



PREPARATION OP THE SILVER SALT OF THE ORGANIC PHOSPHORIC 



ACID. 



The water-soluble barium salt analyzed on p. 9 was transformed 

 into the silver salt as follows: 5 grams were suspended in water and 

 decomposed with a slight excess of dilute sulphuric acid; the barium 

 sulphate was filtered off and the filtrate neutralized to litmus with 

 ammonia. Silver nitrate was added producing a pure white precipi- 

 tate which however rapidly darkened in color. It was filtered, 

 washed in water and dried in vacuum over sulphuric acid under 

 exclusion of light. The substance was then a heavy dark-gray 

 amorphous powder. It was free from all but traces of ammonia. 

 For analysis it was dried at 105° in vacuum over phosphorus pentoxide 

 under exclusion of light but it turned very dark in color. 

 . Found: C = 9.49; H = 1.48; P = 7.89; Ag = 54.85 per ct. 



The substance was free from inorganic phosphate. 



As will be noticed it corresponds very closely in composition to 

 the barium salt from which it was prepared and not to the com- 

 pounds analyzed by Rather. 



PREPARATION OF THE CRUDE ACID FROM WHEAT BRAN BY THE METHOD 



OF RATHER. 



In the preparation of the acid, the directions of the above author 

 were followed as closely as possible. The various operations may 

 be briefly stated as follows: Wheat bran was digested in 0.2 per 

 ct. hydrochloric acid for three hours with frequent stirring. It 

 was then strained through cheesecloth, the residue was washed 

 with water and again strained. The extract was centrifugalized 

 and finally filtered. Copper acetate solution was added in excess 

 and allowed to settle over night. The copper precipitate was freed 

 from the mother-liquor as far as possible by the centrifuge and 

 finally brought on the Buchner funnel and then washed several 

 times in water. It was then suspended in water and decomposed 

 with hydrogen sulphide, filtered and the filtrate evaporated to a thin 

 syrup on the water-bath. This was dissolved in a small quantity of 

 water and rendered strongly alkaline with ammonia and allowed to 



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