456 EXPERIMENT STATION RECORD. 



strength, tbougli sulpliuric acid and barium clilorid reduce the solu- 

 bility in liydrochloric acid somewhat more than in nitric acid, (h) 

 Barium can be almost completely precipitated from either 10 per cent 

 hydrochloric or nitric acid solutions by an excess of sulphuric acid; but 

 in precipitating sulphuric acid by barium chlorid in a 10 per cent 

 hydrochloric acid solution 1 mg. of barium sulphate remains in each 

 100 cc. of the filtrate.— B. w. kilgoee. 



The hydrolysis of raffinose by soluble ferments, E. Bourquelot 

 {Jour. Pharm. et Chim., ser. 0, 3 {189 6), p. 390; ahs. in Ghem. ZUj., ;30 

 {1896), ¥0. 36, Repert.,2). 139). — The author investigated, the action of the 

 m\ evXiw oi AspergiUuH niger on pure raffliiose. One gram of crystal- 

 lized raffinose (0.818 gm. anhydrous raffinose) yielded 0.690 gm. of sugar 

 expressed as dextrose. The rotation decreased from {a) l) = 103.12oto 

 about 50°. According to Scheibler the total hydrolysis of raffinose 

 consists of 2 stages expressed by the reactions : 



(1) 0,„H:,2O,c+H2O = C6H„O6+C,oH22O„; 



(2) (\,Ti,,Ou-^'a,o=i\n,,o,^GMnOs. 



The first reaction would express a final rotation of about 52 to 53°. 

 The hydrolysis had therefore entered the second stage in the author's 

 experiments. Comparisons were also made with the soluble ferment 

 obtained from 2 trade yeasts. Bakers' yeast gave about the same 

 results as Aspergillus, while with a brewers' yeast the hydrolysis con- 

 tinued even further, the final rotation being about 45° and sugar cor- 

 responding to 0.79 gm. being found. — vr. 11. KRua. 



Comparisons of methods of determining citrate-soluble phos- 

 phoric acid in Thomas slag, M. Passon {ZUvltr. angeic. Che^n., 1896, 

 No 10, pp. 286-288). — The following 3 methods were compared on the 

 citrate solution of 50 samples of Thomas slag obtained by the Wagner 

 method : 



(1) Fifty cc. of the citrate solution was heated with 100 cc. of Wag- 

 ner's molybdic solution for 15 minutes in a water bath at 80 to 85° C, 

 stirring 3 times and not allowing the beaker to touch the bottom of 

 the bath. The solution was cooled 1^ to 2 hours, filtered, the precipi 

 tate washed 3 times with 1 per cent nitric acid, dissolved in 2 per cent 

 ammonia, the filter being washed until the filtrate amounted to about 

 100 cc. (about 10 times); 15 cc. of magnesia mixture was then added 

 drop by drop, with stirring, and the solution allowed to stand 2 hours, 

 and filtered. The precijiitate was washed 10 times with 5 per cent 

 ammonia, burned and ignited 5 minutes, and weighed. 



(2) The MUller modification of the above in which the yellow precipi- 

 tate was washed by decantation with 1 per cent HNO:i, dissolved in 2 

 per cent ammonia, the filter washed out 7 times, 50 cc. of ordinary 

 citrate solution and 25 cc. of magnesia mixture added, stirred for 10 

 minutes, and filtered through a Gooch crucible. 



