WARREN, H. E., and WHIPPLE, G. C. The thermophone, a new instrument for determining temperatures: _Tech. Quart._, Vol. 8, pp. 125–52, 1895. Bibliography 110: WEST, F. D. The preparation of standards for the determination of turbidity of water: _Proc. Ill. Water Supply Assoc._, Vol. 6, pp. 49–51, 1914. Bibliography 111: WESTON, R. S. Apparatus for the determination of ammonia in water by the Wanklyn method, and total nitrogen by the Kjeldahl method: _J. Am. Chem. Soc._, Vol. 22, pp. 468–73, 1900. Bibliography 112: ——. The determination of nitrogen as nitrites in waters: _J. Am. Chem. Soc._, Vol. 27, pp. 281–7, 1905. Bibliography 113: ——. The determination of manganese in water: _J. Am. Chem. Soc._, Vol. 29, pp. 1074–8, 1907. Bibliography 114: WHIPPLE, G. C. The observation of odor as an essential part of water analysis: _Public Health Papers and Reports, Am. Pub. Health Assoc._, Vol. 25, pp. 587–93, 1899. Bibliography 115: ——. The microscopy of drinking water, 3d ed., pp. 186–205, John Wiley & Sons, New York, 1914. Bibliography 116: ——, and JACKSON, D. D. A comparative study of the methods used for the measurement of the turbidity of water: _Tech. Quart._, Vol. 13, pp. 274–94, 1900. Bibliography 117: ——, and others. The decolorization of water: _Trans. Am. Soc. Civil Eng._, Vol. 46, pp. 141–81, 1901. Bibliography 118: ——, and PARKER, H. N. On the amount of oxygen and carbonic acid dissolved in natural waters and the effect of these gases upon the occurrence of microscopic organisms: _Trans. Am. Microscopical Soc._, Vol. 23, pp. 103–44, 1901. Bibliography 119: ——, and WHIPPLE, M. C. Solubility of oxygen in sea water: _J. Am. Chem. Soc._, Vol. 33, pp. 362–5, 1911. Bibliography 120: WINKLER, L. W. Die Bestimmung des im Wasser gelösten Sauerstoffes: _Ber._, pp. 2843–54, 1888. Bibliography 121: WOODMAN, A. G., and NORTON, J. F. Air, water, and food, 4th ed., pp. 72–8, John Wiley & Sons, New York, 1914; Bibliography 121a: pp. 85–7; Bibliography 121b: pp. 90–1, 216, and 231; Bibliography 121c: pp. 106–8. MICROSCOPICAL EXAMINATION. The microscopical examination of water consists of the enumeration of the kinds of microscopic organisms (Plankton), and an estimation of their quantity. It may serve any one or more of the following purposes: (1) To explain the presence of objectionable odors and tastes. (2) To indicate the progress of the self purification of streams. (3) To indicate the presence of sewage contamination. (4) To explain the chemical analysis. (5) To identify the source of a water. (6) To aid in the study of the food of fish, shellfish, and other aquatic organisms.