BIBLIOGRAPHY OF LITERATURE. 999 



the precipitate with ammonium carbonate solution, dry and weigh or ignite, 

 moisten with nitric acid and again ignite and weigh. Weight, CuOx 1.034= 

 gallotannin. Journ. Am. Chem. Soc., 1882, 4. 



DAVY, SIR H. This is the first method devised for the estimation of tannin, and con- 

 sisted in titrating with a standard gelatin or glue solution. Phil. Trans., 

 1803,268. 



DURIEU, F. A method employing a standard calcium hypochlorite solution, under 

 certain conditions, after the addition of ferric chloride. Arch. d. Pharin., 22, 

 523; Zeitsch. f. anal. Chern., 24, 273. 



EDER, J. M. A method for tannin of teas based on that of Fleck (vide Wagner's 

 Jsb., 1860, 531, or abstract in this bibliograpy). The tannin is precipitated 

 from water solution, with copper acetate solution ; the precipitate is collected, 

 washed, and ignited, then moistened with nitric acid and again ignited. 1 

 gram CuO=1.3061 grams tannin. Zeitsch. f. anal. Chem., 19, 106; Ding, 

 poly. Jour., 228, 81. 



FEHLJNG. An improvement of Davy's method, consisting in the addition of alum to 

 the glue solution. Jsb., Liebig and Kopp, 1853, 683; Ding. poly. Joum.,130, 

 53. 



FLECK. A method based on the precipitation of tannin by copper acetate. Wag- 

 ner's Jsb., 1860, 531. 



GAUTIER, A. A method employing carbonate of copper for the estimation of tannin 

 in wines. Zeit. f. anal. Chem., 1878, 222 ; Jsb. d. Chem., 1878, 1088. 



GANTTER, F. A permanganate method. Ten cc of the bark solution are saturated 

 with dilute sulphuric acid, heated to boiling point, then permanganate solu- 

 tion is added (3.988 grains permanganate of potassium per 1,000 cc) 1 cc at a 

 time until the color disappears slowly ; boil and then add the permanganate 

 drop by drop. When a precipitate, not dissolved by hard boiling, forms, 

 add 1 cc permanganate and boil until the color disappears. Add oxalic acid 

 (7.951 grams per liter) until the precipitate dissolves and the solution becomes 

 clear, then complete the titration with permanganate. From the total per- 

 manganate, less that required by the oxalic acid, calculate the tannin. 

 Zeitsch. f. angew. Chem., 1889, 57, 577; Jour. Anal. Chem., 4, 83. 



GERLAND. A method based upon the precipitation of tannin by tartrate of antimony 

 and potassium, in the presence of ammonium chloride. Chem. News, 1863, 

 54 ; Zeitsch. f. anal. Chem., 2, 419. 



GINTL, W. This chemist rejected Pribram's method on account of great variations 

 in the results. Zeit. Chem., 1868, 144; Jsb. d. Chem., 21, 888. 



GRASSI, E. A modification of Maumend's method. The tannin is precipitated by 

 barium hydrate; the precipitate is washed with ammonium chloride or 

 nitrate solution, neither of which dissolves the tannate of barium. This 

 latter is dissolved in dilute sulphuric acid and titrated with standard per- 

 raaganate. Ber. chem. Ges., 1875, 257; Jsb. d. Chem., 1875, 989. 



GUENEZ, E. A volumetric method employing a standard tartar emetic solution, with 

 Poirier's green, 4 J. E., as an indicator. The tannin solution is kept at the 

 boiling point during the titration. It is claimed that gallic acid offers no 

 resistance in this method. Compt. Rend., 1890, 532. 



HAMMER. This method employs a piece of animal skin to abstract the tannin 

 from solution. Dr. A. B. Prescott (Organic Analysis, 473) says Hammer's 

 method gives untrustworthy results, Journ. f. prakt. Chem., 81, 159; notes 

 on this method, by Muntz and Ramspacher, Compt. Rend., 79, 380; also, 

 Zeitsch. f. anal. Chem., 13, 462. 



HANDTKE. A method based on the reaction of ferric acetate with tannin. Stand- 

 ardize the iron solution by means of a tannin solution of known strength. 

 In practice add the iron solution to the tannin solution until the precipitate 

 settles and the liquid becomes clear. Method not applicable to coffees and 

 teas. Journ, f. prakt. Chem., 82, 345; Zeitsch. f. anal. Chem., 1, 104. 



