ON COLORING. 65 



perfect purple or scarlet juice, dying linen so that no washing 

 will wear it out. We mark our handkerchiefs and shirts with it." 

 But purple, being a compound of red and blue, is more cheaply 

 dyed by the following method. The cloth must be first colored 

 blue, by either of the methods recommended in this essay. The 

 saxon blue (second method) gives the brightest, but least durable 

 color. It must then be boiled with alum and tartar, as directed 

 for yellow, and afterwards dyed with cochineal, employing from 

 half to two thirds of the quantity required for scarlet. Or, in- 

 stead of using the alum and tartar, the murio-sulphate of tin, as 

 directed for yellow and scarlet, may be used as a mordant, and a 

 more brilliant purple thereby obtained. Silk, previously dyed 

 blue, by the first method, being macerated in the murio-sul- 

 phate of tin, sufficiently diluted, may be made to receive a fine 

 and lasting purple, or violet, according to the shade of blue pre- 

 viously communicated, by dyeing it with cochineal. Some va- 

 rieties of purple and violet n.ay be produced by substituting 

 madder for cochineal, but, though lasting, they will be less beau- 

 tiful. Brazil wood, Nicaragua wood, and in fact whatever will 

 color red, will give, with indigo blue, purples, often lively and 

 beautiful, but they have but little stability. 



ON COTTON. 



Cotton, macerated in a decoction of galls or maple bark, em- 

 ploying about one pound of galls to six of cotton, then dried and 

 afterwards soaked in a saturated solution of equal parts of alum 

 and copperas, being again dried, rinsed, and dyed with its weight 

 of madder, will obtain a fast color, which, by varying the pro- 

 portion of alum and coi)peras, using more alum the lighter you 

 want the shade, may be made to incline more or less to purple 

 or violet. 



GREEN. 



Green is a compound of blue and yellow, and we have inci- 

 dentally mentioned the method of producing it, while treating of 

 those colors. With indigo and quercitron bark, every shade of 

 green may be given to suit the fancy, followir>g the directions 

 9 



