Verdigris is an acetate of copper, of bluish colour, and requires a groundwork. It is not used to any great extent as a panel colour.
The following is a list of compound colours and their application:—
- Pure Grey.—White and black in various proportions.
- Coloured Greys.—Red and green. Blue and orange.
- Straw Colour.—White, chrome yellow, and raw umber.
- Light Buff.—White and yellow ochre.
- Deep Buff.—White, yellow ochre, and red.
- Salmon Colour.—White, yellow, and vermilion.
- Flesh Colour.—White, Naples yellow, and vermilion.
- Orange.—Equal parts of red and yellow.
- Pearl Colour.—White, black, and vermilion.
- Lead Colour.—White and blue, with a little black.
- Stone Colour.—Black, amber, and yellow.
- Canary Colour.—White and chrome yellow.
- Tan Colour.—Burnt sienna, yellow, and raw umber.
- Pea Green.—White and chrome green.
- Sea Green.—Prussian blue and yellow.
- Citron.—Green and orange.
- Chocolate.—Black and Spanish brown.
- Olive.—Umber, yellow, and black.
- Lilac.—White, carmine, and ultramarine blue.
- Purple.—Olive, red, and carmine.
- Violet.—Blue and red.
- Wine Colour.—Purple, lake, and ultramarine blue.
- Dark Brown.—Vandyke brown, burnt sienna, and lake.
- Green.—Blue and yellow in different proportions according to the tone required.
- Marone.—Crimson, lake, and burnt umber.
The above list will enable the painter to mix about all the colours required in coach-painting. A great many shades may be made of each of those given by varying the proportions of the component colours.
A good quality of raw linseed oil should be used, as it works well and dries dead when not used in excess, and it is free from the gumminess found in boiled oil. Raw oil simmered over a gentle fire for two or three hours has its drying qualities improved, more especially if a little sugar of lead be added to it.
Japanners’ gold size is made as follows:—Asphaltum, litharge, or red-lead, each 1 oz.; stir them with a pint of linseed oil, and simmer the mixture over a gentle fire till it is dissolved and the scum ceases to rise, and the fluid thickens on cooling.
The quality of the varnish used is very important. Rubbing varnishes are required to dry firmly in from two to five days, consequently they have not much oil in their composition. A good wearing rubbing varnish should not be rubbed until the fourth or fifth day after being laid on; when rubbed it should not sweat (become glossy) soon after, even in hot weather. Slow-drying rubbing varnish, when allowed to stand a day or so after having been rubbed down, will sweat out in hot weather, and should again be run over with the “rub rag” and fine pumice before another coat is applied.
Rubbing varnish that sweats at all times, soon after being rubbed, is liable to crack and should not be used.
By the use of hard drying varnish the painter is enabled to level his work down, and prepare for the last coat or finishing varnish. This last coating must be of an opposite nature to that on which it is laid if great brilliancy is sought after; and, as its surface must ever be opposed to the action of heat and cold, sunshine and shower, it must possess an elasticity or oily nature that will resist these changes for a great length of time.