[182] Neue Zeitschrift für Rübenzucker-Industrie. Band 3, S. 342; Band 14, S. 286: Zeitschrift des Vereins für die Rübenzucker-Industrie, 1876, S. 692: Dingler’s Polytechnisches Journal, Band 232, S. 461. [183] Sidersky: Traité d’ Analyse des Matières Sucrées, p. 304. [184] Neue Zeitschrift für Rübenzucker-Industrie, Band 14, S. 286. [185] Zeitschrift des Vereins für die Rübenzucker-Industrie, Band 32, S. 861. [186] Spencer’s Handbook for Sugar Manufacturers, p. 42. [187] Bulletin No. 4 of the Chemical Society of Washington, pp. 22, et seq. [188] Vid. op. et loc. cit. 7. [189] Chemiker-Zeitung, Band 19, S. 1830. [190] Vid. op cit. supra, S. 1784. [191] Vid. op. cit. supra, S. 1829. [192] Zeitschrift des Vereins für die Rübenzucker-Industrie, 1895, S. 844. [193] Journal des Fabricants de Sucre, 1895, No. 33. [194] Journal of the American Chemical Society, Vol. 2, p. 387: Agricultural Science, Feb. 1892. [195] American Chemical Journal, Vol. 13, p. 24. [196] Tucker; Manual of Sugar Analysis, p. 287: Wiechmann; Sugar Analysis, p. 51. [197] Sidersky; vid. op. cit., 14, p. 197. [198] Journal of the American Chemical Society, Vol. 18, p. 81: Allen; Commercial Organic Analysis, Vol. 1, p. 291. [199] Handbuch der Physiologisch- und Pathologisch-Chemischen Analyse, S. 286. [200] Kühne und Chittenden; American Chemical Journal, Vol. 6, p. 45. [201] Vid. op. cit. supra, p. 289. [202] Analyst, Vol. 13, p. 64. [203] Journal American Chemical Society, Vol. 18, p. 438. [204] School of Mines Quarterly, Vols. 11 and 12. In a later method (School of Mines Quarterly, Vol. 13, No. 3) Wiechman describes the separation of the sugars by one polariscopic and two gravimetric determinations, one before and one after inversion. The polariscopic examination is made in a ten per cent solution at a temperature of 20°. The gyrodynats of sucrose, dextrose and levulose at the temperature mentioned are fixed at 66.5, 53.5 and -81.9 respectively. The gravimetric determinations are conducted according to the methods already described. In the formulas for calculating the results _a_ represents sucrose, _b_ reducing sugars, _x_ the dextrose, _y_ the levulose, and _d_ the observed polarization expressed in degrees angular measure. The gyrodynats of sucrose, dextrose and levulose divided by 100 are represented by _s_, _d_ and _l_. The calculations are made from the following formulas: (_as_ + _xd_) - _yl_ = _p_. (_as_ + _xd_) = _p_ + _yl_. _xd_ = _p_ + _yl_ - _as_. _p_ + _yl_ - _as_ _x_ = -----------------. _d_ In this calculation the gyrodynat of levulose is about ten degrees lower than that of most authorities. [205] Vid. op. cit., 23, Band 24, S. 869. [206] Vid. op. cit. supra, 1888, S. 782. [207] Neue Zeitschrift für Rübenzucker-Industrie, Band 35, S. 166.