. Methods for the examination of milk; for chemists, physicians and hygienists. Milk. DETERMINATION OF FATS. 39 The optical methods have, moreover, the disadvantage that they are dependent upon the individual perception of each observer. Naturally each eye is not equally sen- sitive in detecting differences of luminosity. Outside conditions under which the test is carried on, also exert an influence on the result. Even for one and the same eye the sensitiveness of the test is not the same in bright sunlight as in cloudy iveather, nor in artificial light, as in daylight, etc. .\lthough these me
. Methods for the examination of milk; for chemists, physicians and hygienists. Milk. DETERMINATION OF FATS. 39 The optical methods have, moreover, the disadvantage that they are dependent upon the individual perception of each observer. Naturally each eye is not equally sen- sitive in detecting differences of luminosity. Outside conditions under which the test is carried on, also exert an influence on the result. Even for one and the same eye the sensitiveness of the test is not the same in bright sunlight as in cloudy iveather, nor in artificial light, as in daylight, etc. .\lthough these methods are not practicable for very accurate work, they are useful to confirm the doubtful re- sults obtained by more exact deter- minations. They are valuable to the physician, the pharmacist, and especially to the market inspectors, to detect occasional adulteration. The processes have the further ad- vantage that the observer need not be especially skilled. For a close decision of the quality of a sample, however, they are not suited, for the reason just stated. The cremometer of Chevalier (Fig. 4) consists of a glass cylinder 20 cm. high and 4 cm. in diameter, with a capacity of 160 c. c. It is provided with a hundred-point scale, the zero mark of which is placed 5 cm. below the top rim. The graduations usually are made only from zero degfrees to 50 degrees. For the test, the apparatus is filled to the zero mark with milk and allowed to stand for four hours in a room where the temperature is moderate and uni-. FiG. 4. The Chevalier Please note that these images are extracted from scanned page images that may have been digitally enhanced for readability - coloration and appearance of these illustrations may not perfectly resemble the original Sommerfeld, Paul; Peters, Albert Theodore, 1868-; Hiltner, Robert Silver. Chicago, A. Eger
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Keywords: ., bo, bookcentury1900, bookdecade1900, booksubjectmilk, bookyear1901
