ARTIFICIAL COLORS. 47 



a teaspoonful of the pulp in a teacup with three teaspoonl'uls of water 

 and add 30 drops of strong hydrochloric acid with a medicine dropper. 

 Set the cup on the stove in a saucepan containing boiling water. Prop 

 a bright iron brad or nail (wire nails are the best and tin carpet tacks 

 will not answer the purpose) into the cup and keep the water in the 

 saucepan boiling for twenty minutes, stirring the contents of the cup 

 frequently with a splinter of wood. Pour out the contents of the cup 

 and examine the nail. If present in an appreciable amount the nail 

 will be heavily plated with copper. 



CAUTION. Be careful not to allow the hydrochloric acid to come in contact with metal* 

 or with the flesh or clothing. 



DETECTION OF TURMERIC. 



In yellow spices, especially mustard and mace, turmeric is often 

 employed. This is especially true of prepared mustard to which a 

 sufficient amount of starch adulterant has been added to materially 

 reduce the natural color. If turmeric be employed to restore the 

 normal shade an indication of that fact may sometimes be obtained by 

 mixing a half teaspoonful of the sample in a white china dish and 

 mixing with it an equal amount of water, and a few drops (4 to 10) of 

 household ammonia, when a marked brown color, which does not 

 appear in the absence of turmeric, is formed. At the present time 

 turmeric or a solution of curcuma (the coloring matter of turmeric) is 

 sometimes added to adulterated mustard in sufficient amount to materi- 

 al^ increase its color, but not to a sufficient extent to give the brown 

 appearance with ammonia described above. In such cases a teaspoon- 

 ful of the suspected sample may be thoroughly stirred with a couple 

 of tablespoonfuls of alcohol, the mixture allowed to settle for fifteen 

 minutes or more and the upper liquid poured off into a clean glass or 

 bottle. To about 1 tablespoonful of the liquid thus prepared and 

 placed in a small clear dish (a glass salt cellar serves excellently) add 

 4 or 5 drops of a concentrated solution of boric acid or borax and 

 about 10 drops of hydrochloric acid, a and mix the solution by stirring 

 with a splinter of wood. A wedge-shaped strip of filter paper about 

 2 or 3 inches long, 1 inch wide at the upper end, and one-fourth inch 

 at the lower end is then suspended by pinning, so that its narrow end 

 is immersed in the solution, and is allowed to stand for a couple of 

 hours. The best results are obtained if the paper is so suspended that 

 air can circulate freely around it, i. e. , not allowing it to touch any- 

 thing except the pin and the liquid in the dish. If turmeric be pres- 

 ent a cherry red color forms on the filter paper a short distance below 

 the upper limit to which the liquid is absorbed by the paper, frequently 

 from three-fourths of an inch to an inch above the surface of the 



Caution: See page 52. 



