FOODS AND DIETARIES 253 



foam. Oleomargarine or poor butter will sputter and crackle 

 like a green stick burning, and with little foam. 



7. Add 2 or 3 tablespoonfuls of Halphen's solution l to an 

 equal amount of salad oil and heat the mixture in a vessel of 

 boiling salt solution, for 10 or 15 minutes. A reddish color 

 indicates cottonseed oil. 



8. (a) Hold an egg between the eye and the light by put- 

 ting it at end of a tube and looking toward a bright light. 

 Presence of dark spots shows that the egg is not perfectly fresh ; 

 absence of air cell at one end shows the same. In eggs long 

 packed, the yolk or the white slightly adheres also, or the egg 

 will adhere to the shell on one side and also have a musty odor. 



(6) Another test. Make a weak salt solution of about 10%. 

 If the eggs float in it, they are not fresh. 



9. Rinse out a glass with small amount of vinegar and 

 allow to stand a number of hours or over night. If the vine- 

 gar was made of wine, there will be a wine odor left in glass ; 

 if of apples, then a fruity odor. 



10. Place a teaspoonful of lemon or orange extract in a test 

 tube and add 2 or 3 drops of hydrochloric acid. No change 

 indicates natural color, turmeric, or naphthol orange (harmless); 

 pink indicates tropseolin or methyl orange; partial decolora- 

 tion, Martius yellow ; complete decoloration, dinitro cresols. 



e. Table Waters 



Note. $12,000,000 of bottled water sold to public and more 

 than $ 1,000,000 imported each year. Most carbonated waters 

 receive their sparkle through artificial treatment by adding the 

 gas of soda water or " vichy." 



Questions 



1. What are the pure food laws of your state ? 



2. Do the pure food laws of your state protect you from 

 adulterated foods shipped in from other states ? 



1 Halphen's solution is made by dissolving J teaspoonful of flowers of sul- 

 phur in some bisulphide of carbon ; mix this with an equal volume of amyl 

 alcohol. 



