It is indispensable to the clearness and delicacy of flesh, that transparent colours only should be admitted. The constant white on the eye, and sometimes the brightest light on the point of the nose, ate the only parts where opaque colours can with propriety be used.
In finishing the hair, the shadows are composed of a deeper tint of the colour which forms the ground work, its strength being increased by the addition of a greater proportion of the mucilage of gum arable; the lights may be taken off with the scraper, or a sharp lancet, and filled in with a little transparent colour of a proper tint.
The deepest shadows of the draperies are composed chiefly of transparent colours, worked with an increased proportion of gum arabic, by which the depth and clear ness of the colours will be greatly increased. Where great richness in the tints of drapery is required, it will often be found of great advantage to lay one colour over another, instead of mixing them together in one tint, as, for instance, a wash of lake or carmine, laid over a tint of vermillion, will produce a crimson tint, almost equal in depth and richness to oil colours, a process analogous to what is called in oil painting glazing. The glazing colour must necessarily be perfectly transparent ; and if the tint glazed in this manner be opaque, the richness of the effect will be greater.
In like manner, if any part of the picture has too much of any particular colour, it w ill be best corrected by a tiansparent wash of its opposite or contrasting co lour ; thus, if the red predominate, a transparent wash of green will subdue it, and bring it into harmony ; if' green be too prevalent, it may be harmonized with red, and so on ; and the finishing touches may be added in a delicate manner, so as to bring up the effect to a proper degree of smoothness.
The scientific arrangement of the colours of the dra pery in a miniature,,is of the greatest importance to its effect. In subjects where delicacy of sentiment ought to predominate, the colours must be modest and sober, without much variety ; in gayer subjects, a greater di versity of colour is admissible, without, however, vio lent contrasts or abrupt transitions, which miniature painting hardly admits of in any case.
In miniature painting, it is of great importance to have a thorough knowledge of the qualities of the va !ions pigments made use of, both as to the tints they form when mixed with one another, and their transpa rency or opacity, as fitting them for the different parts of the work; for although the same tint may be com posed from different pigments, its fitness for any par ticular part of the picture must he determined by the quality of its grain, its smoothness, transparency, or opacity. Thus, in the carnations, the most delicate and transparent pigments only can be admitted ; in woollen stuffs, and other substances of the less flimsy sort, the opaque pigments, (with even an addition of white to increase their consistency,) are most suitable ; while in thin light draperies, transparent colours will be most convenient for the shadows, and the lights may be de licately heightened with opaque colours.
The following are a list of the 'pigments most gene rally used in miniature painting ; and in reference to the above observations, we have arranged them into three classes, viz. Transparent, Semitransparent, and Opaque.
Opaque Colours.
Constant White, Vermillion, Flake White, Indian Red, These colours are usually made up into cakes, and rubbed with water upon a stone plate or tile. The best water colour cakes are those by Newman & Co. and Smith, Warner & Co. of London.
The colours are diluted to a proper consistency with clean water, and worked with hair pencils.
In water colour painting of every kind, the addition of a very minute quantity of ox-gall to the water, will make the colours work with great case, particularly where any greasiness occurs. The ox• gall, as procured from the shambles, may be boiled to dryness in a cup, and in this state it may be preserved for any length of time. A small quantity of this substance in the dry state, not larger than a pin-head, will be sufficient for a wine-glassful of water, and with this the colours are to be wrought. The ox-gall may also be preserved for a long time in the fluid state, by mixing it with a little spirit of wine, or other ardent spirit.