Page images
PDF
EPUB

of Yorkshire, and the analogous substance known as Dinas | bridges and bed plates of reverberatory furnaces, are often clay, which is really nearly pure silica, containing at most made in cast iron with double walls, a current of water about 2 per cent. of bases. Dinas clay is found at various or air being kept circulating through the intermediate places in the Vale of Neath in South Wales, in the form of space. In this way the metal, owing to its high cona loose disintegrated sandstone, which is crushed between ductivity and low specific heat as compared to that of water, rollers, mixed with about 1 per cent. of lime, and moulded is kept at a temperature far below its melting point if the into bricks that are fired in kilns at a very high tempera- water is renewed quickly enough. It is of course necessary ture. These bricks are specially used for the roof, fire in such cases that the circulation shall be perfectly free, in arches, and other parts subjected to intense heat in reverbera- order to prevent the accumulation of steam under pressure tory steel melting furnaces, and, although infusible under in the interior of the casting. This method has received conordinary conditions, are often fairly melted by the heat siderable extension of late years, notably in furnace-smelting without fluxing or corrosion after a certain amount of ex- of iron ores containing manganese, where the entire hearth posure. Ganister, a slightly plastic siliceous sand, is simi- is often completely water-cased, and in some lead furnaces larly used for the lining of Bessemer steel converters; it is where no fire-brick lining is used, the lower part of the found in the neighbourhood of Sheffield. furnace stack being a mere double iron box cooled by water sufficiently to keep a coating of slag adhering to the inner shell which prevents the metal from being acted upon.

Alumina as a refractory material is chiefly used in the form of an hydrated aluminous iron ore known as bauxete, found in the south of France, in Carniola, and in Antrim; but its applications are somewhat special. It It has been found to stand well for the linings of rotatory puddling furnaces, where, under long-continued heating, it changes into a substance as hard and infusible as natural emery. In the Paris Exhibition of 1878 bricks very hard and dense in character, said to be of pure alumina, were exhibited by Muller & Co. of Paris, as well as bricks of magnesia, the latter being specially remarkable for their great weight. They are intended for use at the extreme temperatures obtainable in steel furnaces, or for the melting of platinum before the oxy-hydrogen blowpipe. For the latter purpose, however, lime is generally used; but as this substance has only small stability, it is usually bedded in a casing of fire-brick. Fig. 9 is a section of a lime furnace as used for platinum melting. The flame of the gas jet is introduced through the hole at the top, and plays over the surface of the metal in the hollow below. Oxide of chromium and chromic iron ore have been proposed as refractory crucible materials by Andouin of Paris. The former may be used as a bed for melting platinum in the same way as lime or magnesia, without affecting the quality of the metal.

Furnaces with special Methods of Firing.-In the examples hitherto noticed, the use of solid fuel has alone been considered, whether in admixture with the charge in blast furnaces or burnt upon a grate in reverberatory furnaces. In either case the useful heating effect realized is considerably below that indicated as possible by theory, and for the same reason, namely, that the carbon factor of the fuel is to a considerable extent only partially oxidized, producing carbonic oxide CO, instead of carbonic acid CO2, as it should do if the combustion were complete. This is attended with great loss of heat, unless steps be taken to ensure the subsequent combustion of the carbonic oxide, by bringing it into contact with more air at an appropriate temperature. The production of carbonic oxide is a necessary consequence where coal is used in large masses, the carbonic acid in the gases resulting from complete combustion at any spot being reduced more or less completely to carbonic oxide by contact with the ignited carbon immediately adjacent. To obtain the most perfect combustion it is, therefore, essential that the layer of fuel upon the bars in a grate fire should be as thin as is consistent with preventing the passage of an undue amount of air, which is attended with a strong cooling effect. This condition is, however, only possible in such furnaces as require an oxidizing atmosphere, as, for example, boiler fires and the different forms of calciners.

Ferric oxide, though not strictly infusible, is largely used as a protecting lining for furnaces in which malleable iron is made, a portion of the ore being reduced and recovered in the process. In an oxidizing atmosphere it is indifferent to silica, and therefore siliceous bricks containing a considerable proportion of ferric oxide, when used in flues of boilers, brewers' coppers, &c., and similar situations, are perfectly fire-resisting so long as the heated gas contains a large proportion of unconsumed air. The red firebricks known as Windsor bricks, which are practically similar in composition to soft red sandstone, are of this character.

FIG. 9.-Section of
Lime Furnace.

Furnace Construction. In the construction of furnaces provision has to be made for the unequal expansion of the different parts under the effect of heat. This is especially necessary in the case of reverberatory furnaces, which are essentially weak structures, and therefore require to be bound together by complicated systems of tie rods and uprights or buck staves. The latter are very commonly made of old flat bottom rails, laid with the flat of the flange against the wall. Puddling furnaces are usually entirely cased with iron plates, and blast furnaces with hoops round each course of the stack, or in those of thinner constructions the firebrick work is entirely enclosed in a wrought iron casing or jacket. Such parts as may be subjected to extreme heat and the fretting action of molten material, as the tuyere and slag breasts of blast furnaces, and the fire

Coal-Dust Furnace.-A special method of providing more intimate contact between air and fuel has been adopted in a furnace designed by Mr T. R. Crampton, who grinds the whole of the coal to a fine powder in a flour mill, and propels a current of coal dust and air, mixed in the right proportion for burning, into the combustion chamber representting the fire-place of an ordinary furnace, either by a fan blower or by chimney draught. In the special application of welding iron considerable economy has been obtained with this furnace over ordinary coal-firing, but its use has up to the present time been exceedingly limited.

Gas Furnaces.-A more general remedy has been found in what is known as gas-firing, where the whole of the fuel is of design first imperfectly burned, i.e., converted into carbonic oxide or rather into a mixture of carbonic oxide and nitrogen, by reducing the supply of air through the grate to a minimum and completing the combustion on the fire bridge by a further supply of air introduced through special channels either at ordinary atmospheric temperature or artificially heated. In this case, the fire-place proper is replaced by a gas-producer or gazogene, which may either form one construction with the other parts of the furnace or be separated from them. Fig. 10 represents a gas-producer intended for heating retort furnaces in gas works. The coal is charged into a deep barrel-shaped stack a, terminated below by a small inclined grate b, with flat bars placed edgewise, like the steps of a ladder or the laths of a Venetian blind, allowing sufficient air to pass between for a smothered

1

[blocks in formation]

or slag run at the bottom. Vertical kilns, such as those used for burning limestone and iron ores, are worked in a similar manner, the raw stone going in at the top, and the burnt product falling through holes in the bottom when allowed to do so. With reverberatory calciners, however, where the work is done upon a horizontal bed, a considerable amount of hand labour is expended in raking out the charge when finished, and in drawing slags from fusion furnaces; and more particularly in the puddling process of refining iron the amount of manual exertion required is very much greater. To diminish the item of expenditure on this head, various kinds of mechanical furnaces have been adopted, all of which can be classified under three heads of gravitating furnaces, mechanical stirrers, and revolving furnaces.

[ocr errors]

1. In gravitating furnaces the bed is laid at a slope just within the angle of repose of the charge, which is introduced at the upper end, and is pushed down the slope by fresh material, when necessary, in the contrary direction to the flame which enters at the lower end. This method is used in Styria for burning the dust of spathic iron ore which cannot be put into the kilns with the large lumps. The fuel used is blast furnace gas, the calciners being directly over the furnace top. Gerstenhofer's pyrites burner, another furnace of this class, has a tall vertical chamber heated from below, and traversed by numerous narrow horizontal cross bars at different heights. The ore in fine powder is fed in at the top, through a hopper, in a regular thin stream, by a pair of rollers, and in falling lodges on the flats of the bars, forming a talus upon each of the height corresponding to the angle of rest of the material, which is, however, at short intervals removed to lower levels by the arrival of fresh ore from above. In this way a very large surface is exposed to the heat, and the ore, if containing sufficient sulphur to maintain the combustion, is perfectly burned when it arrives at the bottom; if, however, it is imperfectly sized or damp, or if it contains much earthy matter, the result is not very satisfactory. Stetefeld's furnace, used for the conversion of sulphuretted silver ores into chlorides, is of a somewhat similar character. It is now largely used in the silver mines of the western States of America.

The gas

FIG. 10.-Gas-producer (transverse section).
flue and the strong draught in the latter. From the ex-
ceedingly poisonous nature of carbonic oxide it is of the
utmost importance to prevent the issue of unburnt gas; and
if this cannot be prevented, the escape must be fired when
the charging hole is opened. This is regularly done in
blast furnaces working with gas-collecting flues, and even
the native iron-smelters of India, in starting their small
furnaces with stacks only a few feet high, observe the same
precaution. Another point of equal importance is to pre-
vent the access of air to the gas anywhere except at the
point of ignition. Any leakage of air into the gas flues
must as a rule produce explosion. An ingenious and
efficacious method of establishing the draught in gas-
producers is adopted by Dr C. W. Siemens.
delivery tube rises to a certain height, is then laid
horizontal for a short distance, and finally descends verti-
cally to the original level. The gas in passing along
the horizontal tube loses heat by radiation, and on arriv-
ing at the downward tube is sensibly denser than when it
started, so that the second vertical tube acts as siphon and
maintains constant exhaust on the producer.
In some
cases the gases from the fuel are modified in composition
by an injection of steam from a pipe below the grate e (fig.
10), which, impinging upon ignited coal, is decomposed into
hydrocarbon and carbonic oxide gases. This transforma-
tion is necessarily attended with considerable cooling effect,
from the large amount of heat expended in the decomposi-
tion of water, so that the method is only of limited appli-
cation; but the "richness" or fuel value of the gases is very
considerably increased by its use. It is more particularly
of value with dry or anthracitic coals. The gas-producer
is used with advantage with very inferior fuels, such as peat,
lignite, sawdust, &c., containing much ash and water, and
if the latter be removed by passing the crude gas through
a condenser, according to the method adopted by Lundin
in Sweden, the poorest material, such as wet sawdust, may
be employed for puddling and steel melting, operations that
require the highest attainable temperatures.

0

Mechanical Furnaces.-The introduction and withdrawal of the charges in fusion furnaces is effected by gravitation, the solid masses of raw ore, fuel, and flux being thrown in at the top, and flowing out of the furnace at the taphole

2. Mechanical stirrers constitute a second division of mechanical furnaces, in which the labour of rabbling or stirring the charges is performed by combinations of levers and wheel-work taking motion from a rotating shaft, and more or less perfectly imitating the action of hand labour. They are almost entirely confined to puddling furnaces, and have not been very generally adopted for these.

3. Revolving furnaces, the third and most important division of mechanical furnaces, are of two kinds. The first of these resemble an ordinary reverberatory furnace by having a flat bed which, however, has the form of a circular disk mounted on a central shaft, and receives a slow movement of rotation from a water-wheel or other motor, so that every part of the surface is brought successively under the action of the fire, the charge being stirred and ultimately removed by passing under a series of fixed scraper arms placed above the surface at various points. Brunton's calciner, used in the “burning " of the pyritic minerals associated with tin ore, is the most familiar example of this type. example of this type. The revolving hearth is also represented in Pernot and Pousard's steel-melting furnaces. In these, however, the hearth rotates on an inclined axis, so that the path of its surface is oblique to that of the flame. In the second class of revolving furnaces the working part is a hollow cylinder, between the fireplace and flue, with its axis horizontal or nearly so, whose inner surface represents the working bed. It is mounted upon friction rollers, and receives motion from a special steam

engine by means of a central belt of spur gearing. Furnaces of this kind were first used in alkali works for the conversion of sulphate into carbonate of sodium in the process known as black ash fusion, but have since been applied to puddling in America and elsewhere by Danks and others; but for the latter purpose they are still to some extent in the experimental stage. As calciners they are used in tin mines and for the chlorination of silver ores.

Use of Heated Air.-The calorific intensity of fuel is found to be very considerably enhanced, if the combustion be effected with air previously heated to any temperature between that of boiling water and a dull red heat, the same effect being observed both with solid and gaseous fuel. The latter, especially when brought to the burning point at a high temperature, produces a heat that can be resisted by the most refractory substances only, such as silica, alumina, and magnesia. This is attained in the regenerative furnace of Siemens, detailed consideration of which belongs more properly to the subject of iron.

Economy of Waste Heat and Gas.-In every system of artificial heating, the amount of heat usefully applied is but a small proportion of that developed by combustion. Even under the most advantageous application, that of evaporation of water in a steam boiler where the gases of the fire have to travel through a great length of flues bounded by thin iron surfaces of great heat-absorbing capacity, the temperature of the current at the chimney is generally much above that required to maintain an active draught in the fire-place; and other tubes containing water, often in considerable numbers, forming the so-called fuel economizers, may often be interposed between the boiler and the chimney with marked advantage as regards saving of fuel. In reverberatory and air furnaces used in the different operations of iron manufacture, where an extremely high temperature has to be maintained in spaces of comparatively small extent, such as the beds of puddling, welding, and steel-melting furnaces, the temperature of the exhaust gases is exceedingly high, and if allowed to pass directly into the chimney they appear as a great body of flame at the top. It is now general to save a portion of this heat by passing the flame through flues of steam boilers, air-heating apparatus, or both-so that the steam required for the necessary operations of the forge and heated blast for the furnace itself may be obtained without further expenditure of fuel. The most perfect method of utilizing the waste heat hitherto applied is that of the Siemens regenerator, in which the spent gases are made to travel through chambers, known as regenerators or recuperators of heat, containing a quantity of thin fire-bricks piled into a cellular mass so as to offer a very large heat-absorbing surface, whereby their temperature is very considerably reduced, and they arrive at the chimney at a heat not exceeding 300 or 400 degrees. As soon as the bricks have become red hot, the current is diverted to an adjacent chamber or pair of chambers, and the acquired heat is removed by a current of cool gas or air passing towards the furnace, where it arrives at a temperature sufficiently high to ensure the greatest possible heating effect in combustion. This system being alternative, four regenerators, two for air and two for gas, are required for each furnace; but in some of the newer French patterns of socalled recuperative furnaces, a system of tubular bricks is adopted in the chambers and only the air is heated, the gas being brought hot from the producer to the furnace instead of cooling it first by atmospheric exposure in a long tube in the manner adopted by Siemens. This allows a considerable simplification in the apparatus; only a single regenerator is required working continuously, the flame travelling outwards though one set of passages in the bricks and the air inwards through another; and as the former consists only of burnt gases, no explosion can take place if a communi

[ocr errors]

cation be established between the two currents through a leaking joint or broken brick.

In iron-smelting blast furnaces the waste gases, though not escaping at as high sensible temperatures as those of the furnaces previously considered, are of considerable fuel value, and may render important services if properly applied. Owing to the conditions of the work, which require the maintenance of a sensibly reducing atmosphere, they contain a very notable proportion of carbonic oxide, and are drawn off by large wrought-iron tubes near the top of the furnace and conveyed by branch pipes to the different boilers and air-heating apparatus, which are now as a rule entirely heated by the combustion of such gases. Formerly they were allowed to burn to waste at the mouth of a short chimney place above the furnace top, forming a huge body of flame, which was one of the most striking features of the Black Country landscape at night, but is now less commonly seen than formerly. Perhaps the greatest number of flaming furnaces to be seen at present are those of the Scotch founding iron district about Gartsherrie, Coatbridge, &c.

Figs. 11, 12, and 13 represent a modern furnace heated by gas burnt with hot air as applied to heating

[merged small][merged small][merged small][merged small][merged small][merged small][ocr errors][merged small][merged small][merged small][ocr errors][ocr errors][merged small][merged small][merged small][merged small]
[ocr errors][ocr errors]
[blocks in formation]

heated air; the mixture being effected at a great number of points ensures uniformity of combustion along the whole length of the furnace. The flame, after heating the retorts, descends by passages under the ends of the side retorts in the lower series to a number of arched divisions in the substructure containing the air-heating pipes, which are of cast iron in horse-shoe coils. By this means the temperature of the gases is considerably reduced by the time they reach the chimney flue, the heat intercepted being returned by the air to the combustion chamber.

arranged round the inner lining. Charcoal is the fuel used, and the crucibles stand upon the bottom of the clay lining. When a large body of fuel is required, the cylinder can be lengthened by an iron hoop which fits over the top ring. Deville's portable blast furnace is very similar in principle to the above, but the body of the furnace is FIG. 14. - Sefstrom's formed of a single cast-iron cylinder lined with fire-clay, closed below by a cast-iron plate perforated by a ring of small holes-a hemispherical basin below forming the air-heating chamber.

Portable Blast Furnace.

The literature of furnaces is co-extensive with that of metallurgy. Most of the different patterns in use will be found described and fully illustrated in Percy's and Phillip's Metallurgy, Jordan's Album du Cours de Métallurgie, &c. The atlas to Karsten's great work, and the plates in the Encyclopédie Méthodique, are also of much interest, but the types of apparatus represented are chiefly antiquated and out of use. (H. B.)

Laboratory and Portable Furnaces.-Small air-furnaces with hot plates or sand bath flues were formerly much employed in chemical laboratories, as well as small well as small blast furnaces for crucibles heated with charcoal or coke. The use of such furnaces has very considerably diminished, owing to the general introduction of coal gas for heating purposes in laboratories, which has been rendered possible by the invention of the Bunsen burner, in which the mixture of air and gas giving the least luminous but most powerfully heating flame is effected automatically by the effluent gas. These burners, or modifications of them, have also been applied to muffle furnaces, which are convenient when only a few assays have to be made -the furnace being a mere clay shell and soon brought to a working temperature; but the fuel is too expensive to allow of their being used habitually or on a large scale. Petroleum, or rather the heavy oils obtained in tar refineries, having an equal or superior heating power to coal gas, may also be used in laboratories for producing high temperatures. The oil is introduced in a thin stream upon a series of inclined and channelled bars, where it is almost immediately volatilized and burnt by air flowing in through parallel orifices. Furnaces of this kind may be used for melting cast-iron or bronze in small quantities, and were employed by M. St Claire Deville in experiments in the metallurgy of the platinum group of metals.

Sefstrom's blast furnace, used in Sweden for the assay of iron ores, is one of the most convenient forms of portable furnaces applied to melting in crucibles. It consists of a It consists of a sheet-iron cylinder about 8 or 9 inches in diameter, within which is fixed one of smaller size lined with fire-clay, as shown in part section in fig. 14. The space between the two cylinders serves as a heater and distributor for the blast, which is introduced through the nozzle at the bottom, and enters the furnace through a series of several small tuyeres

FURNITURE is the name, of obscure origin, used to describe the chattels and fittings required to adapt houses, churches, ships, &c., for use. The sculptures, paintings, and metal work of antiquity, of the Middle Ages, and of the Renaissance, now kept in museums and private collections, have, with few exceptions, formed part of decorations or of furniture made for temples, churches, or houses. Most of our ancient bronzes, if not images taken from ancient shrines, are pieces of mirrors, tripods, altar vessels, even the dishes and pans of the kitchen. Wood, ivory, precious stones, bronze, silver, and gold have been used from the most ancient times in the construction or for the decoration of seats, chests, tables, and other furniture, and for the shrines and altars of sacred buildings.

The kinds of objects required for furniture have varied according to the changes of manners and customs, as well as with reference to the materials at the command of the workman, in different climates and countries. Of the furniture of the ancient Egyptians there remain several examples. The British Museum contains six chairs, about the same in height as those now used. One is of ebony, turned in the lathe and inlaid with collars and dies of ivory. It is low, with a back; and both back and legs are strengthened with rails of cane. The seat is of plaited cane slightly hollowed. Another is shaped out of two frames of four pieces of wood each, hinged in the centres of the longer sides, the lower ends carved into the form of the heads of animals; the seat has been made of skin or other flexible material so as to fold flat. Some Egyptian couches and seats had the legs carved like those of panthers; some had the arms or seat supported by figures representing slaves or captives taken in war. They were upholstered with rich stuffs and are accurately represented in wall paintings (see the great French work, Description de l'Egypte). Workmen's tables, massive blocks of wood with four plain legs, and head rests hollowed out, standing 9 or 10 inches high, are preserved in the British Museum,some being of alabaster, probably for the sake of coolness. Painted wooden chests, with convex lids (not hinged), and mummy cases can be seen both in the British Museum and in the Louvre in Paris.

The excavations of Nineveh have brought to light sculptured representations of Assyrian seats. They were massive, the ends of the seat frame projected in the shape of rams' heads; in some instances figures of captives support the arms; in one described by Sir A. H. Layard, two horses resting on the lower bars from front to back support the seat. The seats were cushioned or upholstered with rich materials. An elaborate piece of carved ivory, with depressions to hold coloured glass, agate, &c., from Nineveh, now in the British Museum, has been inlaid into a throne,

77

-showing that such objects were sometimes richly decorated. The carving is apparently of Egyptian origin. The furniture of the Assyrians was more massive, and less varied and elegant in execution, than that of the Egyptians. Greek seats (thronoi) are sculptured in the Parthenon frieze now in the British Museum. They resemble turned wood structures, though perhaps representing bronze. The arms are low and straight, and the backs upright. A curious chair of this kind is represented on one of the bas reliefs from Xanthus (British Museum). In the same collection will be seen statues seated in chairs framed in square bars, the horizontal pieces morticed into the upright, and these details are carefully represented in marble. Certain farfamed gold and ivory statues of colossal size, at Olympia and other places, were represented seated. The bars and frames of the chairs, and of the footstools and pedestals, were constructed of cedar wood, coloured and inlaid with plates of sculptured ivory, and of gold and other precious materials. A sacred chest with carved lid, a table covered with ivory carvings, and other objects in these shrines are described by Pausanias. Unfortunately we have but his verbal accounts of them (see Q. de Quincy, Jupiter Olympien, in which careful engravings are given of their probable shapes). Chairs of the shape in general use forty or fifty years ago (the front and back legs curved outwards, with a plain piece of wood curved to fit the shoulders for the top rail of the back) are not uncommon in paintings on vases. The vase rooms of the British Museum and the Louvre give frequent illustrations of chairs, couches, &c., as well as of the stuffs used in upholstering them. Sumptuous Greek furniture, during the last two centuries B.C., was made of bronze, damascened with gold and silver.

The Romans employed Greek artists and workmen. Their chairs, couches, and seats were of similar shape to those of the Greeks. During meals men reclined on couches each made to hold three persons; a low rail protected the back; three of these couches surrounded the table at entertainments, leaving the fourth side open for service. The decoration consisted of rich coverings, constantly changed to suit the season, or in honour of the guests. Women sat during meals. The sella curulis, a folding cross-shaped seat, was carried in the chariot, and used in the forums, baths, lecture halls, &c. It was often inlaid with ivory. Sellæ, square seats of bronze, were also often carried about, as well as footstools, .the former raising the sitter above the heads of humbler persons. Couches, covered with tilts and curtains, could be carried by slaves, and used as litters. Four silver figures of the 4th century, representing the capital cities of the empire, now in the British Museum, are considered to have ornamented the ends of the poles or shafts of a litter. Tables were of marble, resting on sphinxes or other animals. Dining tables were of wood, curiously veneered, to which a high value was often attached. They rested on tripods or frames of four or of six legs, ornamented with figures, busts, animals, &c., in bronze. Tables were changed with each course. Tables were sometimes protected by rims or borders, sometimes rested on feet of carved ivory. Books and other property were kept in scrinia, round chests that could be fastened. Clothes and provisions had special rooms to hold them. hold them. In the later ages of the empire, in Rome, and afterwards in Constantinople, gold and silver were plentiful for furniture; even cooking and common house vessels were occasionally made in those metals.

The chair of St Peter in Rome, a solid square seat, with pedimental back and panelled with carved ivory, that of St Maximian in the cathedral of Ravenna, round backed, with arms also panelled with carved ivory, and many representations on carved ivory diptychs or tablets, will give the student a correct notion of the furniture of the divided empire. The character of the curule chair

survived and may be recognized in the Bayeux tapestry (St Edward's seat), and in many medieval paintings. The architectural features so prominent in much of the mediæval furniture begins in these Byzantine and late Roman thrones. These features became paramount as Pointed architecture became general in Europe, and scarcely less so during the Renaissance. Most of the mediæval furniture, chests, seats, trays, &c., of Italian make were richly gilt and painted. In northern Europe carved oak was more generally used. The coronation chair in Westminster Abbey, made for Edward I. in the 13th century, has a gabled and crocketed back, is panelled with tracery work, and rests on carved lions, -the whole gilt and painted. State seats in feudal halls were benches with ends carved in tracery, backs panelled or hung with cloths (called cloths of estate), and canopies projecting above. Bedsteads were square frames, the testers of panelled wood, and resting on carved posts. Chests of oak carved with panels of tracery, or of Italian cypress (when they could be imported), were used to hold and to carry clothes, tapestries, &c., to distant castles and manor houses; for house furniture had to be moved from place to place. A chest of the reign of John is kept in the castle of Rockingham. Many can be seen in old parish churches, and in the South Kensington Museum, the Louvre, and many other Continental galleries. Carved stalls covered by elaborate tabernacle work remain in many cathedrals and churches. The Hôtel de Cluny in Paris contains numerous examples of this kind of wood work. Altars were backed by paintings in canopied frames, closed by shutters, which were also painted inside and outside. In some German churches, e.g., the cathedrals of Hildesheim and of Münster in Westphalia, the entire picture (as well as the shutters) was made to open out, showing ingenious receptacles for reliquaries within. Copes and other vestments were kept in semicircular chests with ornamental lock plates and iron hinges; an example is preserved in Wells cathedral. The splendour of most feudal houses depended on pictorial tapestries which could be packed and carried from place to place. Wardrobes were rooms fitted for the reception of dresses, as well as for spices and other valuable stores. Excellent carving in relief was executed on caskets, which were of wood or of ivory, with painting and gilding, and decorated with delicate hinge and lock metal work. The general subjects of sculpture were taken from legends of the saints or from metrical romances.

Renaissance art made a great change in architecture, and this change was exemplified in furniture. Cabinets and panelling took the outlines of palaces and temples; sometimes they were actually constructed in perspective, e.g., a small theatre front at Vicenza, the work of the younger Palladio. Curious internal fittings were arranged in cabinets, still following the details of architectural interiors. In Florence, Rome, Venice, Milan, and other capitals of Italy, sumptuous cabinets, tables, chairs, chests, &c., were made to the orders of the native princes. Vasari (Lives of Painters) speaks of scientific diagrams and mathematical problems illustrated in costly materials, by the best artists of the day, on furniture made for the Medici family. The great extent of the rule of Charles V. helped to give a uniform training to artists from various countries resorting to Italy, so that cabinets, &c., which were made in vast numbers in Spain, Flanders, and Germany, can hardly be distinguished from those executed in Italy. Francis I. and Henry VIII. encouraged the revived arts in their respective dominions. Examples of 16th-century chests, cabinets, tables, seats, sideboards, &c., can be seen in museums, and in many private houses. Pietra dura, or inlay of hard pebbles, agate, lapis lazuli, and other stones, ivory carved and inlaid, carved and gilt wood, marquetry or veneering with thin woods, tortoiseshell, brass, &c., were

« EelmineJätka »