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STAINING IVORY. 



To stain Ivory Green. 



Dissolve some copper or verdigrease in nitrous 

 acid, and soak the ivory in it. 



To stain Ivory Yellow. 



Put a quarter of a pound of alum in a pint of 

 water, boil the ivory in the solution ; then boil 

 it in a decoction of turmeric. 



To stain Ivory Blue. 



Boil it in the sulphate of indigo, and after- 

 wards in a solution of three ounces of white tar- 

 tar in a quart of water. Or it may be first stained 

 green, and then dipped into a solution of pearl- 

 ashes, made strong and boiling hot. 



To stain Ivory Purple. 



Put into nitrous acid one fourth of its weight 

 of sal ammoniac J soak the ivory in it. 



MISCELLANEOUS. 



To make Phosphorus. 



Phosphorus was formerly prepared from urine, 

 and was therefore called phosphorus of urine ; but 

 it is exactly the same substance, from whatever 

 materials it is procured. The following is a pro- 

 cess for procuring it from bones, which consist 

 chiefly of Jime, combined with the phosphoric acid. 



