106 EXPERIMENT STATION RECORD. 



of the above operation. The solution is filtered, a slight excess of pie- 

 cipitated carbonate of lime and a little potassium cbromate are added 

 to tbe filtrate, and the solution titrated with tentli-uormal silver nitrate. 



It is (claimed that while the results by this method are not rigorously 

 exact they are sufficiently so for industrial purposes. 



The following results were on salts of known composition: 



Percentage of potash in different salts. 



Potash- 



present. ^^^^^^_ 



Muriate of potash . . 



do 



Sulphate of potash 

 do 



Per cent. 

 47.80 

 48. 25 

 49.60 

 49.50 



Per cent. 

 47.60 

 48.10 

 49.50 

 49.30 



The quantitative determination of crude fiber in foods and con- 

 diments, G. Baumert {Ztschr. angeiv. Ghent., 1896, No. 13, pp. 408- 

 411). — In a paper read before the German Society of Applied Chemistry 

 the author, after speaking of the difficulty of determining crude fiber 

 in foods which have but little of that constituent, recommends the fol- 

 lowing modification of the Weeude method : Two grams of finely ground 

 air-dry substance is moistened with alcohol and a small amount of tine 

 asbestus fiber added. It is then heated for 1 hour with 100 cc. of dilute 

 sulphuric acid (1.25 per cent.) in a covered beaker immersed in a boil- 

 ing water bath, with frequent stirring. The acid is removed by an 

 asbestus filter, the asbestus and substance washed back, and the whole 

 again treated in the same manner for I hour with 1.1*5 per cent sodium 

 hydroxid. It is then filtered as before, washed, dried, weighed, and 

 ignited as usual, the loss on ignition representing the crude fiber. If 

 the material is rich in fat, treatment with hot 90 per cent alcohol is 

 recommended previous to the analysis. 



The results are given of duplicate determinations on 35 samples of 

 wheat and rye, flour, bran, bread, cocoa, potatoes, etc. A difference 

 of 0.2 per cent occurred only once (cocoa). 



The author shows by several analyses the influence on the amount of 

 crude fiber of the duration of heating with the acid and alkaline solu- 

 tions, results being given for h hour, 1 hour, and 2 hours, and compared 

 with those by Holdefleiss' method. The fiber diminished with increased 

 times of contact, but the author prefers heating for 1 hour. — c. l,. 



PARSONS. 



On the analysis of flour and of fat in wheat and rye flour, E. 



Spaeth [Forscli. Ber. Lehensmtl., 1896, No. 6, pp. 251-259). — The author 

 gives a summary of recent work on the fat of flour, and on the ground 

 of his numerous experiments he advises the use of petroleum ether 

 instead of ordinary ether in the extraction of fat in flour, since in his 



