To dye cotton skein a DUCK'S WING GREEN and OLIVE.
This is performed by a blue ground, next galling, dipping in the black vat, then in the weld dye, then in verdigris, remembering to wash off previously to performing each process.
Olive is to be performed with weld or old fustic, verdigris, and Brazil wood.
Of BROWNS, MAROONS, COFFEE-COLOURS, &c.
It would answer little purpose to enlarge this treatise with a detail of all the possible methods of producing the various shades of these several colours, the whole consisting in the use of galls, verdigris, sulphate of copper, weld, and madder.
By welding a stuff previously maddered for red you may produce a gold colour; and by dipping the same red in a blue vat you obtain a plum colour.
Observations on SILK.
Silk, as it is obtained from the cocoons of the worm, is generally of an orange or yellow colour, more or less dark; in the South of France it is generally very dark: its natural shade is unfavourable to almost all other colours. It is also imbued with a kind of varnish or gum, which makes it stiff and hard; this stiffness is improper in the fabrication of most silk stuff, it is therefore ungummed, as it is called, by the following processes.
On ungumming and boiling silk.
Observe, that throughout the following processes for silk white soap is directed to be used; and, generally speaking, we believe it will be found the best, more especially for the more delicate operations. Yet Mr. M'Kernan, in his process for ungumming silk, directs yellow soap and soft soap in equal parts, and of the same weight as the silk to be used: he adds, however, that different sorts of silk require more or less soap; the best rule he finds, nevertheless, is the same weight of soap as of silk: and he says also, that yellow soap and soft soap of the best quality he finds the best for this purpose.