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free-hand letters are in bad taste on such drawings.

Letters should correspond in conspicuousness or body of colour with the rest of the drawing, not being obtrusive from great heaviness of solid black outline, or unobservable from excessive faintness. Also, violent contrasts of heaviness among neighbouring portions of the title should be avoided; though there may be a gradual change, both of intensity and size, from the most to the least important words of the title.

This should, first of all, not exceed in elaborateness the draughtsman's ability to execute it with perfect neatness and clearness. Then it should agree with the character of the drawing. Plain and simple letters look best on a similar drawing, while a complicated and highly-finished drawing may receive letters of more ornamental character.

Borders. For line drawings the border should be a geometrical design, in lines, with curved or angular corners, or with combinations of straight or curved lines, forming geometrical corner-pieces. These borders may vary in complexity from a rectangular border in single lines to borders which, though geometrical, may be elaborate and elegant. Thus: a plate of varieties of straight horizontal lines may have a plain rectangular border; one including oblique lines may include oblique lines in the border, either as a little tuft in each corner, a truncated corner, or a square set diagonally, &c. Plates embracing curve lines may have quartercircle borders, either convex or concave inwards of which the former have most decision. Such plates may also have little circles for corner-pieces. Borders may sometimes conform in a pleasing manner to the general outline of a drawing. Thus, an arched bridge may have a semi-oval upper border and a square-cornered border at the base of the drawing; and an ornamental device may crown the summit of the korder.

When the drawing is a shaded one, containing, therefore, some free-hand work, the border may be partly free

hand also; but should still be largely geometrical in its design, and should represent a real border of substantial materials, corresponding to the subject of the drawing. Thus, the mouldings and ornaments should represent ornamental metallic castings, carvings in wood, mouldings in plaster, or scrolls and leaves of rolled metal; but garlands, tassels, and tendrils, &c., should not be introduced.

The border to a geometrical drawing should be like the drawing itself in being executed with the drawing pen and brush, as well as with the mapping pen. Free-hand pen borders, representing the products of the soil, with cornucopias, little pen sketches of scenery, or similar agricultural or landscape devices, worked in as corner-pieces, are more appropriate on topographical drawings.

As to colour, primary colours should not be largely introduced into the border; first, since they, when obtrusive, are adapted to ruder or less impressible tastes than the secondary hues, shades, and tints, which are more gratifying to delicate tastes; and secondly, from the impertinent conspicuousness which they may give to the border.

Drawings which are shaded only in sepia or ink, or any dark neutral tint, may have the border done in the same, or in a dark complementary colour. Tinted ink drawings are best finished with a plain ink border.

Indian Ink is used for producing the finished lines of all kinds of geometrical drawing. Being free from acid, it does not injure or corrode the steel points of the instruments. The genuine ink, as it is imported from China, varies considerably in quality; that which answers best for line drawing will wash up the least when other colours are passed over it. This quality is ascertained in the trade, but not with perfect certainty, by breaking off a small por

tion.

If it be of the right quality it will show, when broken, a very bright and almost prismatic-coloured fracture. Indian ink should be used immediately after it is mixed; if re-dissolved it be comes cloudy and irregular in tone,

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In colouring plans of estates, the colours that appear natural are mostly adopted, which may be produced by combining the above. Elevations and perspective drawings are also represented in natural colours, the primitive colours being mixed and varied by the judgment of the draughtsman, who, to produce the best effects, must be in some degree an artist.

Care should be taken in making an elaborate drawing, which is to receive colour, that the hand at no time rest upon the surface of the paper, as it is found to leave a greasiness difficult to remove. A piece of paper placed under the hand, and if the square not very clean, under that also, will prevent this. Should the colours, from any cause, work greasily, a little prepared ox-gall

may be dissolved in the water with which the colours are mixed, and will cause them to work freely.

Shading.-For shading, camel or sable hair brushes, called Softeners, are generally used: these have a brush at each end of the handle, one being much larger than the other. The manner of using the softener for shading is, to fill the smaller brush with colour, and to thoroughly moisten the larger one with water; the colour is then laid upon the drawing with the smaller brush, to represent the dark portion of the shade, and immediately after, while the colour is quite moist, the brush that is moistened with water is drawn down the edge intended to be shaded off; this brush is then wiped upon a cloth and drawn down the outer moist edge to remove the surplus water, which will leave the shade perfectly soft.

If very dark shades are required, this has to be repeated when the first is quite dry.

To tint large surfaces, a large camelhair brush is used, termed a Washbrush. The manner of proceeding is, first, to tilt the drawing, if practicable, and commence by putting the colour on from the upper left-hand corner of the surface, taking short strokes the width of the brush along the top edge of the space to be coloured, immediately following with another line of similar strokes into the moist edge of the first line, and so on as far as required, removing the last surplus colour with a nearly dry brush. The theory of the above is, that you may perfectly unite wet colour to a moist edge, although you cannot to a dry edge without showing the juncture. For tinting surfaces, it is well always to mix more than sufficient colour at first.

Colouring Tracings. It is always best to colour tracings on the back, as the ink lines are liable to be obliterated when the colour is applied. Mix the colours very dark, so that they may appear of proper depth on the other side. If ink or colour does not run freely on tracing cloth, mix both with a little ox-gall.

Cutting Stencil Plates.-The perforations are made through the metal, either by engraving, by etching with nitric acid diluted with about one-third water, or, what is better, by both methods combined. If engraving only is employed, the force necessarily applied to the graver will sometimes stretch the plate unequally, whereas by etching alone, the edges of the perforations are left rough, and the corners imperfect; but if the line be lightly etched, and afterwards cleared with the graver, it may be rendered perfect without any risk of cockling the plate. If the back of the plate is smeared with a little oil, the cuttings will come out clean. Α good ground for the etching of these plates is made by rubbing on them, slightly heated over a spirit lamp, a

cake of heel-ball.

Copper is much better than brass for stencil plates: the metal being softer, it lies closer to the paper upon receiving the pressure of the stencilling brush. This close contact is a very important consideration, as it prevents the hairs of the brush from getting under the plate, and producing rough edges.

Plain stencil alphabets will not be necessary to a draughtsman, if he is a good writer, as they will only save him a little time. A greater saving may be effected by the use of words which are constantly recurring; as Ground plan, Front elevation, Section; or of interiors, as Drawing-room, Kitchen.

For railway or public works, headings of plans may be cut in suitable character and style; also words which are frequently repeated on any particular works, as the name and address of the architect or engineer.

Besides letters and words, there are many devices by the use of which a superior effect may be produced, and much time saved; of these may be mentioned, north points, plates for the representation of surface of country, as plantation, wood, or marsh, corners and borders for finished plans, and many other devices.

Using Stencil Plates. - The brush requires to be squarely and

equally cut, and to be kept moderately clean. If indian ink is used, the largest surface of the cake should be taken to rub the moist brush upon, to get it equally diffused and softened with colour. A cheap kind of ink is sold with stencil plates, which answers better than indian ink, as it runs less upon the drawing and presents a larger surface to the brush.

After the plate has been in use some time, the fine lines and corners become clogged with ink, which may easily be removed by soaking the plate a short time in warm water, and afterwards lightly brushing it upon a flat surface until quite clean. It must be particularly observed that a cloth should at no time be applied to the plate either to clean or to wipe it, as this would be almost certain to catch in some of the perforations, and probably spoil the plate.

If the plate by improper use becomes cockled, it may be flattened, if laid upon a hard flat surface, by drawing a cylindrical piece of metal, as, for instance, the plain part of the stem of a poker, firmly across it several times on each side of the plate.

In using the stencil plate, hold it firmly to the drawing by one edge only, in no instance allowing the fingers to cross to the opposite edge. The general method is, to place the fingers of the left hand along the bottom edge. When the brush is diffused with ink, so that it is just moist, lightly brush it upon a book-cover or pad, so as to free the points from any excess of colour. In applying the brush to the plate, it should be held quite upright, and moved, not too quickly, in small circles, using a constant, equal pressure, as light as ap pears necessary. The stencilling should be commenced at one end of the plate and proceeded with gradually to the other, moving onwards as the perforations appear filled with colour, being particularly careful not to shift the fingers placed upon the plate during the operation. If the plate is very long, after each word the fingers may be shifted, if the plate be held down during

the time firmly by the other hand. Should there not be quite sufficient ink in the brush to complete the device, the plate may be breathed upon, which will moisten the ink attached to the plate. If, after the plate is removed, the device appears light in parts, the plate may be replaced and the defects remedied, if very great care be taken to observe that the previous stencilling perfectly covers the perforations.

In stencilling words or numbers with the separate letters of the alphabet, draw a line where the bottoms of the letters are intended to come, take the separate letters as required and place them upon the line, so that the line just appears in the perforations. That the letters may be upright, it is best that the next letter on the slip used should also allow the line to appear in it. The required distance of the letters apart must be judged of by the eye, a pencil mark being made, after each letter is completed, to appear in the perforation on the near side of the next letter to be stencilled.

With care, a stencil plate will last in constant use for many years; without care, it is practically spoilt by taking the first impression.

Removing Drawings from the Board.-Make a pencil line round the paper with the tee-square at a sufficient distance to clear the glued edge, and to cut the paper with a penknife, guided by a stout ruler. In no instance should the edge of the tee-square be used to cut by. A piece of hard wood, half an inch thick by two inches wide, and about the length of the paper, forms a useful rule for the purpose, and may be had at small cost. The instrument used for cutting off, in any important draughtsman's office, is what is termed a stationer's rule, which is a piece of hard wood of similar dimensions to that just described, but with the edges covered with brass. It is necessary to have the edge thick to prevent the point of the knife slipping over.

Either of the above

rules will also answer to turn the edge of the paper up against when glueing it to the board.

The Frame for a Drawing is to afford a suitable protection to the finished drawing, and hence should be so subordinate in design and colour as not to distract attention from the drawing.

For geometrical drawings, a gilt frame is, in general, preferable to a darkcoloured wooden one. Occasionally the latter style of frame may be appropriate, as in case of a very darkly-shaded drawing on tinted paper, or of a drawing which very completely fills the

paper.

It hardly need be said that a frame of plain mouldings is more appropriate for a geometrical drawing than is a carved or stucco-moulded frame. For ordinary geometrical drawings, nothing is prettier than an Oxford frame of light oak, or a plain gold frame.

Vegetable Parchment is made by dipping ordinary paper, for a few seconds, into a solution, containing one part water to six sulphuric acid; then washing it carefully, to remove every trace of acid.

Indelible Pencil Writing.Lay the writing in a shallow dish, and pour skin med milk upon it. Any spots not wet at first may have the milk placed upon them lightly with a feather. When the paper is wet all over, with the milk, take it up and let the milk drain off, and remove with the feather the drops which collect on the lower edge. Dry carefully.

Pencil Drawings, To fix.-Prepare water-starch, in the manner of the laundress, of such a strength as to form a jelly when cold, and then apply with a broad camel - hair brush, as in varnishing. The same may be done with thin, cold isinglass water or size, or rice water.

Mounting Engravings. Strain thin calico on a frame, then carefully paste on the engraving so as to be free from creases; afterwards, when dry, give two coats of thin size (a piece the size of a small nut in a smail cupful of hot water will be strong enough), finally, when dry, varnish with white hard varnish.

To Renew Manuscripts. Take a hair pencil and wash the part that has been effaced with a solution of prussiate of potash in water, and the writing will again appear if the paper nas not been destroyed.

Uniting Parchment to Paper, or Wood. The surface of the parchment must first be moistened with alcohol or brandy and pressed while still moist upon glue or paste. When two pieces of parchment are to be joined, both must be moistened in this way. It is said that the paper will sooner tear than separate where it has been thus fastened together. Another way is to put a thin piece of paper between the surfaces of parchment and apply the paste. This forms a firm joint, and can with difficulty be separated. Glue and flour paste are best adapted for uniting surfaces of parchment.

Tracing Paper.-1. Wash very thin paper with a mixture of: Spirits of turpentine, 6; Resin, 1; Boiled nut oil, 1, parts by weight, applied with a soft sponge.

2. Brushing over one side of a good, thin, unsized paper with a varnish made of equal parts of Canada balsam and turpentine. If required to take water colour, it must be washed over with ox-gall and dried before being used.

3. Open a quire of double-crown tissue paper, and brush the first sheet with a mixture of mastic varnish and oil of turpentine, equal parts; proceed with each sheet similarly, and dry them on lines by hanging them up singly. As the process goes on, the under sheets absorb a portion of the varnish, and require less than if single sheets were brushed separately.

Transfer Paper is made by rubbing white paper with a composition consisting of 2 oz. of tallow, oz. powdered black-lead, pint of linseed oil, and sufficient lampblack to make it of the consistency of cream. These should be melted together and rubbed on the paper whilst hot. When dry it will be fit for use.

Babbitt's Attrition Metal.Preparing and fitting, melt separately

4 lbs. of copper, 12 lbs. best quality Banca tin, 8 lbs. regulus of antimony, and 12 lbs. more of tin while the composition is in a melted state. Pour the antimony into the tin, then mix with the copper away from the fire in a separate pot.

In melting the composition, it is better to keep a small quantity of powdered charcoal on the surface of the metal. The above composition is called "hardening." For lining the boxes, take 1 lb. of hardening and melt it with 2 lbs. of Banca tin, which produces the lining metal for use. Thus the proportions for lining metal are, 4 lbs. of copper, 8 lbs. of regulus of antimony, and 96 lbs. of Banca tin.

The article to be lined, having been cast with a recess for the lining, is to be nicely fitted to a former, which is made of the same shape as the bearing. Drill a hole in the article for the reception of the metal, say a half or three-quarters of an inch, according to the size of it. Coat over the part not to be tinned with a clay wash, wet the part to be tinned with alcohol, and sprinkle on it powdered sal-ammoniac; heat it till a fume arises from the salammoniac, and then immerse in melted Banca tin, taking care not to heat it so that it will oxidize. After the article is tinned, should it have a dark colour, sprinkle a little sal-ammoniac on it, which will make it a bright silver colour. Cool it gradually in water, then take the former, to which the article has been fitted, and coat it over with a thin clay wash, and warm it so that it will be perfectly dry; heat the article until the tin begins to melt, lay it on the former and pour in the metal, which should not be so hot as to oxidize, through the drilled hole, giving it a head, so that as it shrinks it will fill up. After it has sufficiently cooled remove the former.

A shorter method may be adopted when the work is light enough to handle quickly; namely when the article is prepared for tinning, it may be immersed in the lining metal instead of the tin, brushed lightly in order to

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