Marrone is a retiring colour easily compounded in all its hues and shades by the mixture variously of red, and black or brown; or of any other warm colours in which red and black predominate. A reference to the permanent brown, black, and red or reddish pigments will show to what extent the colour marrone may safely be produced by admixture. In compounding marrone, the brown or black may be itself compounded, before the addition of the red, reddish-purple, or russet, requisite for its conversion. * * * * * 278. _Chica Marrone_. Chica, the red colouring principle alluded to in the ninth chapter, is extracted from the _Bignonia chica_, by boiling its leaves in water, decanting the decoction, and allowing it to cool, when a red matter falls down, which is formed into cakes and dried. Insoluble in cold water, it dissolves in alcohol and alkalies; is precipitated from alkaline solutions by acids without alteration; and is bleached by chlorine. Another variety of the same substance, obtained from Para in Brazil, and known as crajuru, carajuru, or caracuru, behaves in a similar manner. This is said to be superior to the former sort. A chica pigment, brought from South America, and examined by the author, was of a soft powdery texture, and rich marrone colour. Somewhat resembling Rubens' madder in hue, it was equal in body and transparency to the carmine of cochineal, though by no means approaching it in beauty, or even in durability. Simply exposed to the light of a window, without sun, the colour was soon changed and destroyed. Conclusive evidence as this is that the sample submitted to Mr. Field was worthless, it remains to be seen whether all the colours to be derived from chica, by different modes and from different kinds, are equally valueless as pigments. 279. _Chocolate Lead_, or Marrone Red, is a pigment prepared by calcining oxide of lead with about a third of copper oxide, and reducing the compound to a uniform tint by levigation. It is of a chocolate hue, strong opaque body, and dries freely. Like all lead and copper colours, it is blackened by impure air. 280. _Cobalt Marrone._ There is obtainable from cobalt a very rich marrone brown, which, like many other colours, is more beautiful while moist than when dried. Permanent, if carefully made and most thoroughly washed, it is an expensive compound, and must rank among those colours which are interesting in the laboratory but superfluous in the studio. 281. _Madder Marrone_,