Take a perfectly clean piece of glass (plate or picture glass is preferable, as it is less liable to be wavy). Drop on one edge two or three drops of cream at intervals of an inch or so. Then incline piece of glass at such an angle as to cause the cream to flow down surface of glass. The cream, having the heavier body or viscosity, will move more slowly. If several samples of each cream are taken, then the aggregate lengths of the different cream paths may be taken, thereby eliminating slight differences due to condition of glass. FOOTNOTES: [126] From 10 to 16 cents per quart is usually paid for such milks. [127] Much improvement in quality could be made by more careful control of milk during shipment, especially as to refrigeration; also as to the care taken on the farms. The use of the ordinary milking machine (see page 37), would go far to reduce the germ content of milk. [128] Farrington, Journ. Amer. Chem. Soc., Sept., 1896. [129] Hite, Bull. 58, West Va. Expt. Stat., 1899. [130] Milch Zeit., 1895, No. 9. [131] Ibid., 1897, No. 33. [132] Bernstein, Milch Zeit., 1894, pp. 184, 200. [133] Thoerner, Chem. Zeit., 18:845. [134] Snyder, Chemistry of Dairying, p. 59. [135] Doane and Price (Bull. 77, Md. Expt. Stat., Aug. 1901) give quite a full resume of the work on this subject in connection with rather extensive experiments made by them on feeding animals with raw, pasteurized and sterilized milks. [136] Rickets is a disease in which the bones lack sufficient mineral matter to give them proper firmness. Marasmus is a condition in which the ingested food seems to fail to nourish the body and gradual wasting away occurs. [137] De Man, Arch. f. Hyg., 1893, 18:133. [138] Th. Smith, Journ. of Expt. Med., 1899, 4:217. [139] Russell and Hastings, 17 Rept. Wis. Expt. Stat., 1900, p. 147. [140] Russell and Hastings, 21 Rept. Ibid., 1904. [141] Russell and Hastings, 18 Rept. Ibid., 1901. [142] Russell, Bull. 44, Wis. Expt. Stat. [143] Russell, 22 Wis. Expt. Stat. Rept., 1905, p. 232. [144] Russell, 12 Wis. Expt. Stat. Rept., 1895, p. 160. [145] De Schweinitz, Nat. Med. Rev., 1899, No. 11. [146] Harding and Rogers. Bull. 182, N. Y. (Geneva) Expt. Stat., Dec., 1899. [147] Jensen, Milchkunde und Milch Hygiene, p. 132. [148] 22 Wis. Expt. Stat. Rept., 1905, p. 236. [149] Shockley, Thesis, Univ. of Wis., 1896. [150] Marshall, Mich. Expt. Stat., Bull. 147, p. 47. [151] Fleischmann, Landw. Versuchts Stat., 17:251. [152] Babcock and Russell, Bull. 54, Wis. Expt. Stat., Aug. 1896. CHAPTER VII. BACTERIA AND BUTTER-MAKING.