Popular Technology Volume II Part 11

9. Spirits of turpentine is produced by distilling with water the resinous juice or sap of several species of the pine. The residuum, after distillation, is the turpentine of commerce. Spirits of turpentine is mixed with paints, to cause them to dry with rapidity.

Like oil, it improves with age, and it is sold in the same manner by the common wine measure.

10. White lead, and several other princ.i.p.al paints, are purchased in their crude condition, and reduced to a state of minute division in paint-mills. They are afterwards mixed with boiled oil, and put up in kegs of different sizes for sale. Many articles, however, are pulverized, and sold in a dry state. The preparation of paints is commonly a distinct business, and very few painters seem to be acquainted with the mode in which it is performed.

11. In mixing colors for house and sign painting, white lead forms the basis of all the ingredients. This the color preparer, or the painter himself, modifies and changes by the addition of coloring materials, until it is tinged with the proposed hue. The pigments derived from vegetable bodies, produce, when first applied to surfaces, a brilliant effect; but they cannot long resist the combined influence of air and light, while the mineral colors, in the same exposure, remain unchanged.

12. Painters, in the execution of their work, commonly lay on three coats of paint. In communicating a white, the two first coats are composed of white lead and oil; and in the last, spirits of turpentine is subst.i.tuted for the oil, for the inside work. For the outside of buildings, especially in warm and dry climates, this liquid is inapplicable, since it causes the paint to crack and flake off. It is, however, frequently used, when the painter is compelled to do his work at too low a rate, or when he is regardless of his reputation.

13. For other colors, the composition for the different coats is the same, except for the two last, in which other coloring substances are added to the materials just mentioned, to give the proposed hue. The tools for painting houses are few in number, and consist chiefly of brushes of different sizes, made of hog's bristles.

14. _Graining_ is understood, among painters, to be the imitation of the different species of scarce woods used for the best articles of furniture. But the manner in which this kind of work is executed can be hardly gathered from a concise description, although it may be easily learned from a practical exhibition of the process by a painter.

15. _Ornamental painting_ embraces the execution of friezes and other decorative parts of architecture on walls and ceilings. The ornaments are drawn in outline with a black-lead pencil, and then painted and shaded, to give the proper effect. Some embellishments of this kind are executed in gold-leaf, in the same manner with gold letters on signs. This kind of work is called _gilding in oil_.

16. Painting in oil, as applied to the execution of designs, seems to have been invented, or at least to have been brought into notice, in the early part of the fifteenth century, by John Van Eyck, of Flanders. Before this time, house-painting, so far as the exterior was concerned, could have been but little, if at all, practised.

17. One profitable branch of common painting is that of painting and lettering signs. In performing this kind of work, the sign is first covered with two or three uniform coats of paint. The letters are next slightly sketched with chalk or a lead-pencil, and then formed in colors with a camels'-hair brush. When the letters are to be gilt, the process, so far, is precisely the same. The leaf is laid upon the letters, while the paint is in a tenacious state, and is suffered to remain untouched, until the oil has become dry, after which the superfluous gold is removed. The whole is then covered with an oil varnish, which, in plain lettering, completes the operation.

THE GLAZIER.

1. Glazing, as practised in this country, consists chiefly in setting panes of gla.s.s in window-sashes. In the performance of this operation, the glazier first fits the panes to the sash by cutting away, if necessary, a part of the latter with a chisel; he then fastens the gla.s.s slightly with little pieces of tin, which have been cut to a triangular shape; and, lastly, he applies _putty_ at their junction with the sash, and by this means confines them firmly and permanently to their place. The putty is made of linseed-oil and whiting. The latter of these materials is chalk cleared of its grosser impurities, and ground in a color-mill.

2. Plain glazing is so simple, that no person need serve an apprentices.h.i.+p to learn it; and there are but few who confine their attention to this business exclusively. It is commonly connected with some other of greater difficulty, such as that of the carpenter and joiner, or house and sign painter, but with the latter more frequently than any other.

3. When the gla.s.s, as received from the manufacturer, may not be of the size and shape required for a proposed application, the panes are cut by means of a diamond fixed in lead, and secured by a ferrule of bra.s.s, which is fastened to a small cylindrical handle of hard wood.

This instrument is used, in conjunction with a straight edge, like a pencil in ruling lines on paper for writing. The gla.s.s is afterwards broken in the direction of the fracture, by a slight pressure downwards.

4. Although gla.s.s windows seem to us to be indispensable to comfort, yet gla.s.s had been manufactured many centuries in considerable perfection, before it was applied to this purpose. The houses in oriental countries had commonly no windows in front, and those on the other sides were provided with curtains, or with a moveable trellis-work in summer, and in winter with oiled paper.

5. In Rome and other cities of the empire, thin leaves of a certain kind of stone called _lapis specularis_ were used. Windows of this material, however, were employed only in the princ.i.p.al apartments of great houses, in gardens, sedans, and the like. Paper made of the Egyptian papyrus, linen cloth, thin plates of marble, agate, and horn, seem likewise to have been used.

6. The first certain information we have of the employment of gla.s.s panes in windows, is found in the writings of Gregory of Tours, who flourished in the last quarter of the sixth century. This prelate states that the churches were furnished with windows of colored gla.s.s, in the fourth century after Christ. The oldest gla.s.s windows now in existence were of the twelfth century, and are in the Church of St.

Denis, the most ancient edifice of this description in France.

7. aeneas Sylvius accounted it one of the most striking instances of splendor which he met with in Vienna, in 1458, that most of the houses had gla.s.s windows. In France, all the churches had these conveniences in the sixteenth century, although there were but few in private dwellings. Talc, isingla.s.s, plates of white horn, oiled paper, and thinly shaved leather, were used instead of gla.s.s. A similar state of things prevailed in England.

8. The gla.s.s used for the windows of churches and other public buildings, after the fourth century, was very commonly intrinsically colored or superficially painted. Painting on gla.s.s had its origin in the third century, and at first it consisted in the mere arrangement of small pieces of gla.s.s of different colors in some sort of symmetry, and const.i.tuted a kind of mosaic-work.

9. Afterwards, when more regular designs came to be attempted, such as the human figure, the whole address of the artist went no farther than drawing the outlines of the objects in black on gla.s.s resembling in color the subjects to be represented. The art, in this state of advancement, was spread over a great part of Europe.

10. About the beginning of the fifteenth century, a method of fixing metallic colors in gla.s.s by means of heat was discovered, and from this the art derived great advantages. It flourished most during the fifteenth and sixteenth centuries; but it declined in the following age, and in the eighteenth century it was very little practised in any country. It has, however, been partially revived, of late, in Germany.

A very good specimen of this kind of painting, as well as of colored gla.s.s, may be seen in St. John's Church, in Philadelphia.

[Ill.u.s.tration: TURNER.]

THE TURNER.

1. Turning is a very useful art, by which a great variety of articles are almost exclusively manufactured. Besides this, it const.i.tutes a considerable part of the operations of several trades and occupations, such as the chairmaker, machinist, cabinet-maker, bra.s.s-founder, &c., since every substance of a solid nature can be submitted to the process.

2. Turning is performed in a _lathe_, an apparatus constructed in various ways, according to the particular purposes to which it is to be applied, although, in all cases, the general principle of its operation is the same. The kind represented in the above picture, is used for plain or circular turning in wood. On examination, it will be perceived, that two wheels of different sizes make essential parts of it. On the extended axle of the smaller one, is fastened the piece to be turned; and immediately in front of this is the _rest_, on which the cutting instrument is supported during the performance of the operation.

3. When the material to be turned is wood, it is commonly cut to the proper length with a saw, and brought to a form approaching to the cylindrical by means of an axe or drawing-knife. It is next fastened in the lathe. This is done by different means, varying according to the particular form of the thing to be turned. In plain circular turning, as applied to bed-posts, legs of tables, and rounds for chairs, the piece is supported at each end. That at the left hand is driven upon a piece of steel, which has been screwed upon the extended axle of the small wheel; and the other end is fixed upon a steel point, placed in an upright moveable piece called a _puppet-head_.

4. In case the wood is to be turned on the inside, as in making a bowl, cup, or mortar, the piece is supported altogether at one end, by means of a hollow cylinder of wood, bra.s.s, or iron, called a _chuck_, which receives it on one side, and on the other is screwed upon the end of the axle. The axle is sometimes called the _mandril_, and any extension of it, by means of a piece added to it for a centre, on which anything may be turned which will admit of a hole through it, is denominated an _arbor_.

5. The tools used in turning wood and ivory, are _gouges_ and _chisels_ of different sizes and shapes. In using these, they are placed upon the _rest_, and brought in contact with the revolving material of the proposed figure. The gouge is employed in cutting away the rough exterior, and the chisel, in producing a still further reduction, and a greater smoothness of surface.

6. In working in very hard wood and in ivory, the _grooving tool_, a sharp pointed instrument somewhat similar to the graver, is used in the first part of the operation; and by this the grain of the substance is cut into contiguous grooves, and prepared for an easy reduction by the chisel. The instruments for turning metals are numerous, but they differ in some respects from those for cutting wood.

7. In almost every kind of turning, a tool called the _calipers_ is necessary for measuring the diameters of the work. In its form, it bears some resemblance to the compa.s.ses or dividers. One or both of the legs, however, are curved; and one kind of this instrument has four legs, two curved, or two straight, at each end, with a pivot in the centre, on which it is opened and shut. The former of these is employed in measuring the dimensions of outside work, and the latter, for that on the inside. This kind is called the _in-and-out_ calipers; and it is especially useful in turning a cylinder, or pin, which shall exactly fit an internal cylinder already made, and _vice versa_.

8. There is but little difference in the management of turning different substances. The princ.i.p.al thing to be attended to is to adapt the velocity of the motion to the nature of the material; thus wood will work best with the greatest velocity that can be given to it. Bra.s.s should have a motion about half as quick as wood, and iron and steel still less; for, in operating on metallic substances, the tool is liable to become hot, and lose its temper; besides which, a certain time is requisite for the act of cutting to take place.

9. When compared with many other mechanical operations, the art of turning may be considered as perfect in its accuracy and expedition.

The lathe is, therefore, resorted to for the performance of every work of which it is capable; nor is its use confined to the production of forms perfectly cylindrical, for it can be easily made to produce figures of irregular shape, such as lasts, gunstocks, &c.

10. The lathe was well known to the Greeks and Romans, as well as to many other nations of antiquity. Diodorus Siculus, who wrote in the time of Julius Caesar and Augustus, says that it was invented by one Talus, a nephew of Daedalus. Pliny ascribes it to Theodore, of Samos, and mentions one Thericles, who had rendered himself very famous by his dexterity in managing the lathe. The Greek and Latin authors frequently mention this instrument; and, among the ancients, it was customary to express the accuracy and nicety of a thing by saying, it was formed in a lathe.

[Ill.u.s.tration: CABINET MAKER.]

THE CABINET-MAKER, AND THE UPHOLSTERER.

THE CABINET-MAKER.

1. It is the business of the cabinet-maker to manufacture particular kinds of household furniture, such as tables, stands, bureaus, sideboards, desks, book-cases, sofas, bedsteads, &c., as well as a certain description of chairs made of mahogany and maple. Many of the operations of this business are similar to those of the carpenter and joiner, although they require to be conducted with greater nicety and exactness.

2. The qualifications of a finished cabinet-maker are numerous and of difficult acquisition; so that they are seldom concentrated in any single individual. He requires not only a correct taste, but also a knowledge of drawing, architecture, and mechanics, besides the abilities of a good practical workman.

3. A knowledge of drawing is especially useful in designing new articles of furniture, or in improving the form of those which have been already introduced. It also enables the artist to determine with accuracy what would be the general effect of furniture, were different pieces of it placed in any proposed apartment; and, combined with architectural knowledge, it enables him to adapt the style of his wares to that of the building for which they may be designed.

4. In general, the principles of this business are fixed, so far as relates to the mode of operating in the execution of the work; yet continual changes are made in the form and construction of its various articles, so as to keep pace with the advancement of correct taste, or with the caprices of fas.h.i.+on. In fact, the shapes of furniture are almost as changeable as those of female dress; and this causes many expensive pieces to fall into disuse, while others are introduced, which, for a time, are considered indispensable to comfort, and which in turn enjoy but a temporary favor.

5. The cabinet-maker uses various kinds of wood in the manufacture of his wares; but those which are most frequently employed in the United States are pine, maple, poplar, cherry, black walnut, white oak, beach, mahogany, and rose, all of which are abundant in this country, except the last two. Mahogany is brought in great quant.i.ties from the West Indies and South America; rose-wood is obtained chiefly from the West Indies and Brazil, although it was first introduced into notice from the island of Cyprus.

6. The applicability of mahogany to the manufacture of cabinet-ware, was accidentally discovered in London, about the year 1724. A physician, named Gibbons, received a present of some of the planks from his brother, a sea-captain, who had brought them from the West Indies, chiefly as ballast. The doctor was, at that time, erecting a house, and, supposing them to be adapted to the purposes of building, gave them to his workmen, who, on trial, rejected them as being too hard to be wrought with their tools.

7. A cabinet-maker was next employed to make a candle-box of some of it, and he also complained of the hardness of the timber; but, when the box was finished, it outshone in beauty all the doctor's other furniture. He then required a bureau to be made of the same kind of material; and this, having been finished, became the subject of exhibition to his friends, as a piece of remarkable beauty. The wood was immediately taken into general favor, and it soon became an article of merchandise of considerable importance.

8. In giving the reader a view of the operative part of this business, we have selected the bureau as affording the best means of ill.u.s.tration. The material which composes the frame and drawers of this piece of furniture, is commonly some kind of soft wood, such as pine or poplar; and this is faced with thin layers of mahogany in those parts which are to be exposed to view.