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two shallow dishes and heat each for a few minutes. Into 

 one of the dishes put a piece of woolen material, and into the 

 other dish put a piece of cotton material. Let the liquids 

 come to a boil and then remove the material. Rinse the 

 woolen and cotton strips thoroughly in water and state 

 what effect the dye had on each. Can you suggest any 

 reason why one kind of material might dye better than 

 another kind ? 



EXPERIMENT 69. INDIRECT DYEING. MORDANTING 



(a) Mix ten drops of alizarin coloring matter with 200 

 c.c. of water and divide into three portions. Heat one por- 

 tion and put into it specimens of woolen and cotton ma- 

 terial. After the liquid has come to a steady boil, remove 

 the materials to be dyed, and rinse them in water. State 

 what effect the coloring matter had on each kind of ma- 

 terial. 



(b) Dissolve 4 gm. of iron acetate in about 200 c.c. of 

 water. In another dish mix icc.c. of ammonia with looc.c. 

 of water. 



Dip the woolen cloth first into the iron acetate solution, 

 then into the ammonia solution. After it has been thor- 

 oughly soaked in these two solutions, boil it in the alizarin 

 solution. Rinse as before and state the result. 



(c) Repeat the process for cotton and silk. State the 

 result. 



Which process of dyeing is more satisfactory, direct or 

 indirect dyeing ? 



