216 



whifch does not add to their nutritive value; that is, a substance (water) is mixed with 

 them N such a manner as to reduce their quality or strength. 



WheuHne oyster is removed from the bed by dredging or tonging, the inside of the 

 shell contains a considerable amount of dirt and sand. In order to remove this the 

 oysters are sometimes placed on floats at some convenient place in the salt water. 

 Here, probably at the beginning of the ebb tide, they open their shells and "drink." 

 Since the water in which they are placed is at the same concentration as that of the 

 bed, however, there is no plumping or other change in their appearance except that 

 during this process they appear to blow the dirt and sand from the shell and if the water 

 be clean the oyster is fairly clean. They are then taken to the oyster house, shucked, 

 and washed to remove the slime with which they are covered. It is said by shippers 

 that this slime will rapidly produce decomposition and must be removed before the 

 oysters are shipped. This washing, however, should not be prolonged more than is 

 absolutely necessary for proper cleansing. 



During the last season a study was made of the oysters in various parts of the country 

 in order to secure data, if possible, by which oysters that had been properly treated 

 might be distinguished from those which had been treated with an excessive amount 

 of water. Seventy samples of oysters were taken from beds in various sections of the 

 seacoast of the United States and sent to the laboratory without any treatment what- 

 ever. Other samples from the same beds were merely washed with water for a suffi- 

 cient time to remove sand and dirt; while still other samples were soaked in water for 

 a length of time varying from one hour to twenty-four hours. 



When the samples arrived at the laboratory they were examined as follows: First, 

 the total weight was taken, then the sample was strained through a colander and the 

 solid meats and liquors weighed separately. Fifty grams of the oysters were then 

 placed in a beaker with 200 cc of cold water and the whole heated in such a manner 

 that the water was brought to the boiling point in about fifteen minutes. The boiling 

 was continued for fifteen minutes, w r hen the water was poured off as completely as 

 possible, the oysters were cooled five minutes and weighed. From the figure thus 

 obtained the per cent loss on boiling was determined. It was found that by con- 

 tinuing the boiling for a longer period than fifteen minutes the results were not greatly 

 increased. 



Another portion of the solid meats was passed through a meat chopper and the total 

 solids, ash, and sodium chlorid determined in the usual way. The percentages of 

 total solids and ash and sometimes of sodium chlorid were also determined in the 

 liquor. From the figures obtained by the examination of the solid meats and liquors, 

 together with their respective weights, the per cent of total solids in the original 

 sample was calculated. In the majority of cases samples of the salt water were taken 

 from the respective oyster beds and their content of sodium chlorid determined. 



SIMPLE TESTS FOR DETECTING BLEACHING IN FLOUR. 

 By A. L. WINTON and E. J. SHANLEY. 



The Griess-Ilosvay method for determining nitrites," originally designed for water 

 analysis, is generally recognized as the best means of detecting artificial bleaching in 

 flour. Commercial unbleached flour contains no appreciable amount of nitrous acid, 

 free or combined, while that bleached with nitrogen peroxid contains amounts increas- 

 ing with the degree of bleaching. The quantitative process of determining nitrous 

 acid, although not a tedious one, is, however, unnecessarily laborious when only 

 qualitative results are desired. It involves the preparation of a standard nitrite 

 solution and comparison of the intensity of the color produced in this solution with 



aSutton: Volumetric Analysis, 9th ed., 1904, p. 449. 



