Page:Encyclopædia Britannica, Ninth Edition, v. 13.djvu/91

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I N L I N N 81 Marking Ink. The ink so called, used principally for marking linen, is composed of a salt of silver, usually the nitrate, dissolved in water and ammonia, with a little provisional colouring matter and gum for thickening. The colour resulting from the silver salt is developed by heat and light ; and the stain it makes, although exceedingly obstinate, gradually becomes a faint brownish-yellow. The following yields a good marking ink. Equal parts of nitrate of silver and dry tartaric acid are triturated in a mortar, and treated with water, when a reaction takes place, resulting in the formation of tartrate of silver and the liberation of nitric acid. The acid is neutralized, and at the same time the silver tartrate is dissolved by the addition of ammonia, and this solution with colouring matter and gum forms the ink, which may be used with an ordinary steel pen. Gold and silver inks are writing fluids in which gold and silver, or imitations of these metals, are suspended in a state of fine division. In place of gold, Dutch leaf or mosaic gold is frequently substi tuted, and bronze powders are also used for preparing a similar kind of ink. The metallic foil is first carefully triturated into a fine paste with honey, after which it is boiled in water containing a little alkali, and then repeatedly washed in hot water and dried at a gentle heat. A solution is prepared consisting of 1 part of pure gum arabic and 1 part of soluble potash glass in 4 parts of dis tilled water, into which the requisite quantity of the metallic powder prepared as above is introduced. Owing to the superior covering nature of pure gold, less of the metal is required than is necessary in the case of silver and other foils ; but the proportion varies according to the colour and condition of the surface upon which the ink is to be used. In general 1 part of foil to 3 or 4 parts of solution is sufficient. The metallic lustre of writing done with this solution may be greatly heightened by gently polishing with a burnishing point. Indelible or incorrodible ink is the name given to various combi nations of lamp-black or other carbonaceous material with resinous substances used for writing which is exposed to the .weather or to the action of strong acids or alkaline solutions. An ink having great resisting powers may be conveniently prepared by rubbing down Indian ink in common ink till the mixture flows easily from the pen. Other combinations have more the character of coloured varnishes. Sympathetic inks are preparations used for forming characters which only become visible on the application of heat or of some chemical reagent. Many chemicals which form in themselves colourless solutions, but which develop colour under the influence of reagents, may be used as sympathetic ink, but they are all of little practical utility. Characters written in a weak solution of galls de velop a dark colour on being treated with a solution of copperas ; or, vice versa, the writing may be done in copperas and developed by the galls solution. Writing done in various preparations develops colour on heating which fades as the paper cools. Among such substances are solutions of the acetate and the chloride of cobalt and of the chloride of nickel. Very dilute solutions of the mineral acids and of common salt and a solution of equal parts of sulphate of copper and sal-ammoniac act similarly. Characters traced in a weak solu tion of nitrate of silver darken on exposure to light, and tcrchloride of gold solution develops a purple colour on exposure. ( J. PA. ) INLAYING is a method of ornamentation, by incrusting or otherwise inserting in one material a substance or sub stances differing therefrom in colour or nature. The art is practised in the fabrication of furniture and artistic objects in all varieties of wood, metal, shell, ivory, and coloured and hard stone, and in compound substances ; and the possible combinations, styles, and varieties of effect are exceedingly numerous. There are several special classes of inlaying, long established and well recognized, which may be here enumerated and defined, details regarding most of which will be found under their separate headings. In the ornamental treatment of metal surfaces Niello decoration, applied to silver and gold, is an ancient and much practised species of inlaying. It consists in filling up engraved designs with a composition of silver, copper, lead, and sulphur incorporated by heat. The composition is black, and the finished work has the appearance of a drawing in black on a metallic plate. An art, analogous in effect, called Bidri, from Eider in the Deccan, is practised in India. In bidri work the ground is an alloy of zinc, with small proportions of copper and lead, in which shal low patterns and devices are traced, and filled up with thin plates of silver. When the surface has been evened and smoothed, the bidri ground is stained a permanent black by means of a paste the chief ingredients of which are sal-ammoniac and nitre, leaving a pleasing contrast of bright metallic silver in a dead black ground. The inlaying of gold wire in iron or steel is known as DAMASKEENING (q.v., vol. vi. p. 793). It has been very largely practised in Persia and India for the ornamentation of arms and armour, being known in the latter country as Kuft work or Kuftgari. In Kashmir, vessels of copper and brass are very effectively inlaid with tin, an art which, like many other decorative arts, appears to have originated in Persia. In the ornamental inlaying of metal surfaces the Japanese display the most extraordinary skill and perfection of work manship. In the inlaying of their fine bronzes they use principally gold and silver, but for large articles and also for common cast hollow ware (for with them inlaying is common and profuse) commoner metals and alloys are employed. In inlaying bronzes they generally hollow out and somewhat undercut the design, into which the ornamenting metal, usually in the form of wire, is laid and hammered over so as to be firmly inserted. Frequently the famous lacquer work of the Japanese is inlaid with mother-of-pearl and other substances, in the same manner as is practised in ornamenting lacquered papier-mach6 among Western communities. The Japanese also practise the various methods of inlaying alluded to under DAMAS- KEENING. The term Mosaic (see MOSAIC) is generally applied to inlaid work in hard stones, marble, and glass, but the most important class of mosaics those which consist of innumerable small separate pieces do not pro perly come under the head of inlaying. Inlaid mosaics are those in which coloured designs are inserted in spaces cut in a solid ground or basis, such, for example, as the modern Florentine mosaic, which consists of thin veneers of precious coloured stones set in slabs of marble. The famous Taj Mahal at Agra is an example of inlaid mosaic in white marble, and the art, carried to that city by a French artist, is still practised by native workmen. Pietra Dura is a fine variety of inlaid mosaic in which hard and expensive stones agate, carnelian, amethyst, and the like are used in relief in marble. Under the head BUHL WORK (vol. iv. p. 446) will be found a description of the kind of inlaying, principally brass and tortoiseshell, which was introduced and carried to great perfection by Andre" Charles Boule, who gave his name to this particular style of inlaying. Closely allied to buhl work is the more ancient Tarsia work or Marquetry, which consists of inlaid woods alone. It has been practised from remote times, but came into prominence, for the decoration of furniture, in Italy during the Renaissance epoch, and has continued to be a favourite decorative art, varying with changing tastes and styles, to the present day. From India, under the name of Bombay boxes, comes a variety of minute and elaborate work, inlaid in geometrical patterns on wood. The inlaying materials consist of tin wire, sandal wood, sapan wood, ebony, ivory, and stag s horns, and the effect produced by the combination of minute pieces of these various substances is altogether peculiar and distinctive. Certain kinds of ENAMEL (vol. viii. p. 182) might also be included among the varieties of inlaying. INNKEEPERS, LAW RELATING TO. By the common law of England innkeepers are under certain peculiar obligations, the most important of which are the duty of supplying accommodation to such travellers as may desire it, and their responsibility for the safety of the goods belonging to persons staying in their inns. An inn is a i place "instituted for passengers and wayfaring men," and in a recent case, in which the proprietor of a restaurant was prosecuted for refusing refreshment on demand, it was held that a tavern, or shop for the retail of spirits across the counter, is not within the definition, and that a person XIII. n