First liquify the wax, resin, and turpentine varnish, over a slow fire, in an earthen pot, then add the colouring matter, previously mixing it in another pot, with a very small quantity of the liquified composition, and stirring it well with a wooden pestle, so that the colouring ingredients may be intimately and smoothly blended; then add, by degrees, the whole of the ingredients, and when they have acquired their due heat, by being placed again over the fire, the injection will be ready for immediate use. A quantity of the ingredients of these injections may be kept prepared without the colouring matters, which may be added in their proper proportions, _pro re nata_. The ingredients become brittle by frequent melting, and turpentine varnish must be occasionally added. The same rules apply to the mixture of the following: _Formulæ for fine Injections._ _Red._--Brown spirit varnish, white spirit varnish, _a.a._ 4 ℥. Turpentine varnish,* 1 ℥. Vermilion, 1 ℥. _Yellow._--The same, substituting King’s yellow, 1-1/4 ℥. _White._--Substituting best flake white, 2 ℥. _Light blue._--Substituting fine blue smalt, 1-1/2 ℥. Best flake white, 1-1/4 ℥. _Dark blue._--Substituting blue verditer, 4 ℥. _Black._--Lamp-black, 1/2 ℥. * The varnishes go by measure. _Formulæ for Minute Injections._ The size which constitutes the principal part of these formulæ, is made in the following manner: Take the finest and most transparent glue, one pound, break it into pieces about the size of a nutmeg; put it into an earthen pot, and pour on it three pints of cold water, let it stand twenty-four hours, stirring occasionally with a stick; then set it over a slow fire for half an hour, or until the glue is perfectly dissolved; skim off the froth from the surface and strain it through flannel; then add the colouring ingredients. _Red._--Size, one pint--Vermilion, 3-1/2 ℥. _Yellow._ " " King’s yellow, 2-1/2 ℥. _White._ " " Best flake white, 3-1/2 ℥. _Blue._ " " Fine blue smalt, 6 ℥. _Green._ " " Crystallized verdigris, 2 ℥. " " Best flake white, gamboge, _a.a._ 8 ℈. _Black._ " " Lamp-black, 1 ℥. _Cold Injections._