PURE AND IMPURE FOODS. 



421 



The Macmillan Co., 66, 5th Avenue, New 

 York, have just brought out " Nature 

 Study in Elementary Schools," a First 

 Reader, prepared by Mrs. L. L. W. Wilson, 

 Ph.D., of the Philadelphia Normal School. 

 It is designed to teach little children to love 

 and study Nature. The clouds, the winds, 

 the birds, the flowers, the animals live in a 

 new sense for the children. They hold gay 

 little conversations, each revealing his mis- 

 sion among men and appealing to the fancy, 

 the love and the sympathy of the child. 

 This reader should prove an invaluable aid 



to all in the home or in the school who 

 would turn the eyes and thoughts of chil- 

 dren away from the mere second-hand 

 knowledge of Nature, as taught by books, 

 to Nature herself in her great playgrounds 

 of the woods and the fields. 



Mr. Hornaday's book on Taxidermy 

 came to hand, and is the only good work 

 of the kind I ever saw. A. B. Cameron, 

 Che-main-us, Vancouver Island, B. C. 



PURE AND IMPURE FOODS. 



ADULTERATION OF FOODS. 



A well known chemist says that wheat 

 flour is subjected to a far greater amount 

 of adulteration than all other flours and 

 meals. In its physical characteristics it is 

 a white, fine powder with only the slightest 

 yellow tinge. To judge of the color the 

 sample should be examined in thin layers, 

 with a light not too strong. The flour 

 should be free from acidity and its odor 

 sweet and agreeable. When pressed with a 

 smooth surface no bran should be revealed 

 to the naked eye or the lens. The hand 

 plunged into it should not experience a 

 cooling efifect. When pressed in the hand 

 it should retain its shape for some time. A 

 microscopic examination should reveal no 

 foreign matter such as starches of other 

 cereals, fungi or weed seeds. 



The same authority says : 



The practice of preserving various kinds 

 of food in hermetically sealed receptacles 

 has become so common that far more at- 

 tention should be given to canned food 

 which is on the market than it receives at 

 the present time, and methods for its ex- 

 amination should be adopted. The appear- 

 ance of the cans themselves should first be 

 noted. The ends should be slightly con- 

 cave, since the contents are sterilized by 

 means of heat and a contraction of volume 

 must necessarily follow cooling. If the 

 ends of the can be convex, some decompo- 

 sition is indicated. In the case of bottled 

 goods, the pressure on the cork should be 

 observed since even the slightest pressure 

 tending to expel the cork is an indication 

 that some decomposition has taken place 

 after the goods were put up. Marked cor- 

 rosion on the inside of the can is often an 

 indication of the presence of metals in solu- 

 tion. No food which is capable of corrod- 

 ing metal receptacles should be preserved 

 in them. In canned corn, corrosion may be 

 sometimes due to the presence of sodium 

 sulphite, which is added for the purpose of 



bleaching the corn. In such cases dark 

 nodules of tin sulphid are also found at the 

 edge of the can. 



Coloring matter is also very commonly 

 used, especially with food of a marked red 

 or green color, such as tomatoes, catsups, 

 some varieties of meat, peas, beans and 

 pickles. The salts of several metals are of- 

 ten present, sometimes having been added 

 intentionally, at other times due to care- 

 lessness or the use of improper receptacles. 

 Among these metals the most important 

 are copper, lead, tin and zinc. A slight 

 amount of copper may be normal to many 

 vegetables. A somewhat larger amount 

 may come from the use of copper utensils; 

 but if the utensils be kept clean, and ordi- 

 nary care exercised in the preparation of 

 the food, only a slight amount of the metal 

 will be introduced in this way. The pres- 

 ence of more than 10 milligrams of copper 

 per kilogram of the food may be taken as 

 sufficient evidence that copper has been in- 

 tentionally added. This practice is only re- 

 sorted to for the purpose of giving a marked 

 green color to foods to which a portion of 

 the public has been educated to ascribe a 

 green or unnatural brightness, especially 

 peas, beans and cucumber pickles. Zinc 

 has in a few cases been added for the same 

 purpose, but its use as an agent in pre- 

 serving the coloring matter has not become 

 at all general. Its presence in canned food 

 is very common, but is almost always due 

 to its use as a flux in soldering. 



Lead comes from the use of inferior tin 

 plate or, more commonly, solders which 

 are much too soft. The tin plate employed 

 which is exposed to the contents of the can 

 should contain less than 10 per cent, of lead. 

 Owing to the lack of legislation on the sub- 

 ject in this country, however, the solders 

 commonly used by our canners contain 

 from 40 to 60 per cent, of lead, and not only 

 is a large amount of this solder exposed to 

 the contents of the can in the seams, but it 

 often happens that one or more pellets of 



