_Carmine_, is an impalpable powder, and the fairest red we know of: it serves for coloring the sections of masonry, the plans of houses, and all kinds of military buildings; as likewise their elevation; but then it is made of a paler color. It is also used for drawing red lines in plans, to represent walls. It is of a high price, but a little will go a great way. It must be mixed with a little gum-water. _Verdigrease_, or _sea-green_, used in drawings, is either liquid in small phials, or mixed in little pots or shells, &c. it serves to color wet ditches, rivers, seas, and in general to represent all watery places; it is most soluble in vinegar; and mixed with vinegar makes a fine green ink. _Sap-green_, is a stone of a faint yellowish green, when liquefied with clear water: but when mixed with a little sea green, it makes a beautiful grass-green; but, as all mixed _colors_ are liable to fade, if _verdigrease_ can be had, it will be much better. _Sap-green_ is very cheap. _Gum-bouge_, is a fine yellow gum. It may be dissolved in water, but requires no other gum: it serves to color all projects of works; as likewise to distinguish the works unfinished from those that are complete. It serves also to color the trenches of an attack. _Indigo_, is in small cakes, and very cheap; it serves to color iron, and roofs of buildings which are covered with slates: it must be well ground upon a smooth stone or glass, and mixed with a little gum-water. _Prussian blue_, is a kind of friable substance of an exceeding fine blue: it is used to represent the color of blue cloth in drawing encampments, battles, &c. It must be well ground, and mixed with a little gum-water. _Smalt_, also a good sort of blue, and may be used for the same purposes. _Ultramarine_, is an impalpable powder, and of a very delicate sky-blue. It is a _color_ of high price. _Umber_, is a yellowish brown _color_ in powder: when it is mixed with gum-water, it serves to color dry ditches, sand, and all kinds of earth. By mixing a little red ink with it, it will make a wood _color_. If some tobacco-leaves be steeped in clear water for several hours, and filtered through a woollen cloth, or brown paper, with a little red ink mixed with it, it will make the best earth or wood _color_, as lying smoother than any other. _Gum-water_, is best when it is made some time before it is used; for which purpose take some _gum arabic_ and steep it in clear water for some hours, ’till it is dissolved; then strain it through a woollen cloth or brown paper, and preserve it in phials, well stopped, ’till wanted.