CHEMISTRY. 1021 



A considerable quantity of lecithin was prepared from wheat sprouts. 

 This was found to be identical with that obtained from other sources. 



A new method for determining crude fiber in foods and feed- 

 ing stuffs, J. Konig (Ztschr. Untersuch. Nahr. u. Genussmtl., 1898, JVo. 

 1, p. 3). — The author states that the Weende method gives altogether 

 too high results, since as high as 40 per cent of the pentoses contained 

 in plants remain undissolved in the crude fiber; and that Schulze's 

 method leaves as high as 30 per cent of the pentoses undissolved. By 

 the use of glycerin containing sulphuric acid the author has obtained 

 results which agree well and are believed to be more accurate. Three 

 grams of air-dry material are mixed in a 500 cc. porcelain dish with 

 200 cc. of glycerin (1.23 sp. gr.) containing 4 gm. of concentrated sul- 

 phuric acid, and heated for one hour in a steam-pressure apparatus at 

 three atmospheres. The contents of the fiask are diluted with 200 to 

 250 cc. of boiling water and filtered while hot on an asbestus filter, the 

 residue being washed with 300 to 400 cc. of boiling water, with 50 cc. of 

 warm alcohol (about 03 per cent), and finally with a warm mixture of 

 alcohol and ether until the filtrate is colorless. The filter and contents 

 are dried and weighed, incinerated, and the difference in weight before 

 and after incineration taken as crude fiber. In the absence of a pres- 

 sure apparatus the determination can be made in a 000 cc. fiask of 

 Schott glass, heating one hour with a reOnx condenser at 131 to 133°, 

 i. e., maintaining the glycerin mixture at boiling. The crude fiber 

 obtained by this method is said to contain a maximum of 6.02 per cent 

 of pentoses and 0.1 to 0.4 per cent of nitrogenous substance. 



Note on the determination of nitrogen as practiced at the agri- 

 cultural experiment station of Aisne, France (Bui. St«. Agron. 

 Laon, 1897, pp. 58-62, Jig. 1). — The modification of the Kjeldahl method 

 which is used at this station is as follows: To 1 gm. of finely ground 

 material in a 200 cc. flask add a small drop of mercury (about h gm.) 

 and 20 cc. of 06° sulphuric acid, and heat on a sand bath until the sub- 

 stance is completely dissolved. This usually requires about half an 

 hour. Then bring gradually to boiling temperature, heating first over 

 a wire gauze, then iu the direct flame of the lamp. In about three- 

 quarters of an hour the solution is completely decolorized. Wash the 

 contents of the digestion flask into a liter distillation flask with about 

 100 cc. of distilled water, add in two portions 100 cc. of caustic soda 

 solution of a density of 1.375 and 5 cc. of a solution of 200 gm. of 

 sodium sulphid in 1 liter of water, then add 15 to 20 gm. of granulated 

 zinc and connect the distillation flask with a bulb tube, the lower arm 

 of which is 1 cm. in diameter and the upper end sharply bent down- 

 ward to connect with a long tube 4 to 5 mm. in diameter which dips 

 into the flask containing the standard acid. This standard acid con- 

 tains 35 gm. of pure sulphuric acid per liter, corresponding exactly 

 with 1 centigram of nitrogen. The caustic potash solution used for 

 titrating the acid corresponds, volume for volume, with the acid, thus 

 avoiding the necessity of calculating results. 



