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but with every care, it will still wash | may be dissolved in the water with up more or less.
which the colours are mixed, and will Colours.--For colouring drawings, cause them to work freely. the most soluble, brilliant, and trans Shading.–For shading, camel or parent water-colours are used ; this sable hair brushes, called Softeners, are particularly applies to plans and sec generally used: these have a brush at tions. The colour is not so much each end of the handle, one being much intended to represent that of the mate larger than the other. The manner of rial to be used in the construction, as using the softener for shading is, to fill to clearly distinguish one material from the smaller brush with colour, and to another employed on the same work. thoroughly moisten the larger one with
The following table shows the colours water; the colour is then laid upon the most employed by the profession : drawing with the smaller brush, to re
present the dark portion of the shade, Carmine or Crimson For brickwork in plan or
and immediately after, while the colour Lake .. .
S section to be executed.
is quite moist, the brush that is moistPrussian Blue
of brickwork to be re ened with water is drawn down the
moved by alterations. edge intended to be shaded off; this Venetian Red Brickwork in elevation.
brush is then wiped upon a cloth and Violet Carmine Granite. Raw Sienna .. English timber (not oak). drawn down the outer moist edge to Burnt Sienna.. Oak, teak.
remove the surplus water, which will Indian Yellow Fir timber,
leave the shade perfectly soft. Indian Red .. Mahogany. bepia
If very dark shades are required, this .. .. Concrete works, stone,
., Burnt Umber . Clay, earth.
has to be repeated when the first is SCast iron, rough wrought
quite dry. Dark Cadmium
To tint large surfaces, a large camelGun netal. Gamboge .. .. Brass.
hair brush is used, termed a WashIndigo .. .. .. Wrought iron (bright). brush. The manner of proceeding is, Indigo, with a little } Steel (bright).
first, to tilt the drawing, if practicable, Lake .. . Hooker's Green . Meadow land
and commence by putting the colour on Cobalt Blue .. .. Sky effects.
from the upper left-hand corner of the And some few others occasionally for special
surface, taking short strokes the width purposes.
of the brush along the top edge of the
space to be coloured, immediately folIn colouring plans of estates, the lowing with another line of similar colours that appear natural are mostly strokes into the moist edge of the first adopted, which may be produced by line, and so on as far as required, recombining the above. Elevations and moving the last surplus colour with a perspective drawings are also repre nearly dry brush. The theory of the sented in natural colours, the primitive above is, that you may perfectly unite colours being mixed and varied by the wet colour to a moist edge, although judgment of the draughtsman, who, to
vou cannot to a dry edge without showproduce the best effects, must be in ing the juncture. For tinting surfaces, some degree an artist.
it is well always to mix more than sufCare should be taken in making an ficient colour at first. elaborate drawing, which is to receive Colouring Tracings. - It is alcolour, that the hand at no time rest | ways best to colour tracings on the upon the surface of the paper, as it is back, as the ink lines are liable to be found to leave a greasiness difficult to obliterated when the colour is applied. remove. A piece of paper placed under Mix the colours very dark, so that they the hand, and if the square is not very may appear of proper depth on the clean, under that also, will prevent ilis. || other side. If ink or colour does not Should the colours, from any cause, run freely on tracing cloth, mix both work greasily, a little prepared ox-gall with a little ox-gall.
Cutting Stencil Plates.-The equally cut, and to be kept moderately perforations are made through the metal, ! clean. If indian ink is used, the largest either by engraving, by etching with ! surface of the cake should be taken to nitric acid diluted with about one-third rub the moist brush upon, to get it water, or, what is better, by both me equally diffused and softened with cothods combined. If engraving only is lour. A cheap kind of ink is sold with employed, the force necessarily applied stencil plates, which answers better to the graver will sometimes stretch the than indian ink, as it runs less upon plate unequally, whereas by etching the drawing and presents a larger suralone, the edges of the perforations are face to the brush. left rough, and the corners imperfect; After the plate has been in use some but if the line be lightly etched, and time, the fine lines and corners become afterwards cleared with the graver, it clogged with ink, which may easily be may be rendered perfect without any removed by soaking the plate a short risk of cockling the plate. If the back time in warm water, and afterwards of the plate is smeared with a little oil, lightly brushing it upon a flat surface the cuttings will come out clean. A until quite clean. It must be partigood ground for the etching of these cularly observed that a cloth should at plates is made by rubbing on them, no time be applied to the plate either slightly heated over a spirit lamp, a to clean or to wipe it, as this would cake of heel-ball.
be almost certain to catch in some of Copper is much better than brass for the perforations, and probably spoil the stencil plates: the metal being softer, it plate. lies closer to the paper upon receiving If the plate by improper use becomes the pressure of the stencilling brush. cockled, it may be flattened, if laid upon This close contact is a very important a hard flat surface, by drawing a cylinconsideration, as it prevents the hairs drical piece of metal, as, for instance, of the brush from getting under the the plain part of the stem of a poker, plate, and producing rough edges. firmly across it several times on each
Plain stencil alphabets will not be side of the plate. necessary to a draughtsman, if he is a In using the stencil plate, hold it good writer, as they will only save him firmly to the drawing by one edge only, a little time. A greater saving may be in no instance allowing the fingers to effected by the use of words which are cross to the opposite edge. The general constantly recurring; as Ground plan, method is, to place the fingers of the Front elevation, Section; or of interiors, left hand along the bottom edge. When as Drawing-room, Kitchen.
the brush is diffused with ink, so that it For railway or public works, head is just moist, lightly brush it upon a ings of plans may be cut in suitable cha book-cover or pad, so as to free the racter and style; also words which are points from any excess of colour. In frequently repeated on any particular applying the brush to the plate, it should works, as the name and address of the be held quite upright, and moved, not architect or engineer.
too quickly, in small circles, using a Besides letters and words, there are constant, equal pressure, as light as ap. many devices by the use of which a pears necessary. The stencilling should superior effect may be produced, and I be commenced at one end of the plate much time saved; of these may be men- | and proceeded with gradually to the tioned, north points, plates for the re other, moving onwards as the perforapresentation of surface of country, as tions appear filled with colour, being plantation, wood, or marsh, corners and particularly careful not to shift the borders for finished plans, and many fingers placed upon the plate during the other devices.
operation. If the plate is very long, Using Stencil Plates. — The after each word the fingers may be hrush requires to be squarely and shifted, if the plate be held down during the time firmly by the other hand. I The Frame for a Drawing Should there not be quite sufficient ink is to afford a suitable protection to in the brush to complete the device, the the finished drawing, and hence should plate may be breathed upon, which will be so subordinate in design and colour moisten the ink attached to the plate. as not to distract attention from the If, after the plate is removed, the device drawing. appears light in parts, the plate may For geometrical drawings, a gilt frame be replaced and the defects remedied, if is, in general, preferable to a darkvery great care be taken to observe that coloured wooden one. Occasionally the the previous stencilling perfectly covers latter style of frame may be appropriate, the perforations.
as in case of a very darkly-shaded In stencilling words or numbers with drawing on tinted paper, or of a the separate letters of the alr.habet. drawing which very completely fills the draw a line where the bottoms of the paper. letters are intended to come, take the İt hardly need be said that a frame of separate letters as required and place plain mouldings is more appropriate for them upon the line, so that the line just a geometrical drawing than is a carved appears in the perforations. That the or stucco-moulded frame. For ordinary letters may be upright, it is best that geometrical drawings, nothing is pretthe next letter on the slip used should tier than an Oxford frame of light oak, also allow the line to appear in it. The or a plain gold frame. required distance of the letters apart Vegetable Parchment is made must be judged of by the eye, a pencil by dipping ordinary paper, for a few mark being made, after each letter is seconds, into a solution, containing one completed, to appear in the perforation part water to six sulphuric acid ; then on the near side of the next letter to be washing it carefully, to remove every stencilled.
trace of acid. With care, a stencil plate will last in Indelible Pencil Writing.constant use for many years; without Lay the writing in a shallow dish, and care, it is practically spoilt by taking pour skin med milk upon it. Any spots the first impression.
not wet at first may have the milk Kemoving Drawings from placed upon them lightly with a feather. the Board.- Make a pencil line round When the paper is wet all over, with the paper with the tee-square at a suf the milk, take it up and let the milk ficient distance to clear the glued edge, drain off, and remove with the feather and to cut the paper with a penknife, the drops which collect on the lower guided by a stout ruler. In no instance edge. Dry carefully. should the edge of the tee-square be Pencil Drawings, To fix.-Preused to cut by. A piece of hard wood, pare water-starch, in the manner of the half an inch thick by two inches wide, laundress, of such a strength as to form and about the length of the paper, forms a jelly when cold, and then apply with a a useful rule for the purpose, and may broad camel - hair brush, as in varnishbe had at small cost. The instrument ing. The same may be done with thin, used for cutting off, in any important cold isinglass water or size, or rice draughtsman's office, is what is termed water. a stationer's rule, which is a piece of Mounting Engravings.hard wood of similar dimensions to that Strain thin calico on a frame, then carejust described, but with the edges covered fully paste on the engraving so as to be with brass. It is necessary to have the free from creases; afterwards, when dry, edge thick to prevent the point of the give two coats of thin size (a piece the knife slipping over. Either of the above size of a small nut in a smail cupful rules will also answer to turn the edge of hot water will be strong enough), of the paper up against when glueing it finally, when dry, varnish with white to the board.
To Renew Manuscripts. - | 4 lbs. of copper, 12 lbs. best quality Take a hair pencil and wash the part | Banca tin, 8 ito. regulus of antiincos, that has been effaced with a solution of and 12 lbs. mcre of tin while the am. prussiate of potash in water, and the | position is in a melted state. Pour the writing will again appear if the paper | antimons into the tin, theo mii with aas not been destroyed.
the copper away from the tire in a Uniting Parchment to Paper, separate pot. or Wood.—The surface of the parch In meiting the composition, it is ment must first be moistened with alcohol better to keep a small quantity of or brandy and pressed while still moist powdered charcoal on the surface of the upon glue or paste. When two pieces metal. The abore composition is calied of parchment are to be joined, both “hariening." For lining the boses, must be moistened in this way. It is | take 1 lb. of hardening and melt it with said that the paper will sooner tear than | 2 lbs. of Banca tin, which produces the separate where it has been thus fastened lining metal for use. Tous the pretogether. Another way is to put a thin portions for lining metal are, 4 ios. of piece of paper between the surfaces of copper, 8 lbs. of regulas of antimony, parchment and apply the paste. This and 96 lbs. of Banca tin. forms a firm joint, and can with diffi The article to be linel, having been culty be separated. Glue and flour cast with a recess for the linics, is to paste are best adapted for uniting sur le nicely fitied to a former, which is faces of parchment.
made of the same shape as the bearing. Tracing Paper.-1. Wash very Drill a hole in the article for the rethin paper with a mixture of: Spirits ception of the metal, say a haif or of turpentine, 6; Resin, 1; Boiled nut three-quarters of an inch, according to oil, 1, parts by weight, applied with a the size of it. Coat over the part not soft sponge.
to be tinned with a clar wash, wet the 2. Brushing over one side of a good, part to be tinned with alcohol, and thin, unsized paper with a varnish made sprinkle on it powdered sal-ammoniac; of equal parts of Canada balsam and heat it till a fume arises from the sal. turpentine. If required to take water ammoniac, and then immerse in melted colour, it must be washed orer with Banca tin, taking care not to heat it so ox-gall and dried before being used. that it will oxidize. After the article
3. Open a quire of double-crown tissue is tinned, should it hare a dark colour, paper, and brush the first sheet with a sprinkle a little sal-ammoniac on it, mixture of mastic varnish and oil of which will make it a bright siiver turpentine, equal parts; proceed with colour. Cool it gradually in water, each sheet similarly, and dry them on then take the former, to which tie lines by hanging them up singly. As article has been fitted, and coat it over the process goes on, the under sheets with a thin clay wash, and warm it so absorb a portion of the varnish, and re that it will be perfectly dry; heat the quire less than if single sheets were article until the tin begins to meit, las brushed separately.
it on the former and pour in the metal, Transfer Paper is made by rub which should not be so hot as to bing white paper with a composition oxidize, through the drilled hole, giring consisting of 2 oz. of tallow, 4 oz. pow it a head, so that as it shrinks it will dered black-lead, piat of linseed oil, 1 fill up. After it has sufficiently cooled and sufficient lampblack to make it of remove the former. the consistency of cream. These should A shorter method may be adopted be melted together and rubbed on the when the work is light enough to paper whilst hot. When dry it will be handle quickly; namely when the arfit for use.
ticle "s prepared for tinning, it may be Babbitt's Attrition Metal. immersed in the lining metal instead of Preparing and fitting, melt separately | the tin, brushed lightly in order to renove the sal-ammoniac from the sur- | markable influence on the colour, and face, placed immediately on the former particularly on the tenacity of the alloy. and lined at the same heating.
The former becomes more red, and the Blanched Copper.-Fuse 8 oz. latter stronger. The scum forming on of copper and oz. of neutral arseni-| the surface by this addition ought to cal salt, with a flux made of calcined | be removed before the metal is cast. borax, charcoal dust, and powdered | Tin and copper are liable to separation glass.
in cooling; this can be prevented, at Yellow Brass.-30 parts of zinc least partly, by turning the mould conand 70 of copper in small pieces.
taining the fluid metal, and keeping it YELLOW BRASS, for Turning.– in motion until it is chilled. (Common article.) — Copper, 20 lbs.; Copper and lead unite only to a zinc, 10 lbs.; lead from 1 to 5 oz. certain extent: 3 lead and 8 copper is Put in the lead last before pouring off. I ordinary pot metal. All the lead may
Red Brass, for Turning.-Copper, be retained in this alloy, provided the 24 lbs.; zinc, 5 lbs.; lead, 8 oz. Put osject to be cast is not too thick. in the lead last before pouring off. When the cast is heavy, or much lead
RED BRASS, free, for Turning. is used, it is pressed out by the copper Copper, 160 lbs.; zinc, 50 lbs.; lead, in cooling. 1 lead, 2 copper, separates 10 lbs.; antimony, 44 oz.
lead in cooling-it oozes out from the Another Brass, for Turning. porcs of the metal : 8 copper and 1 lead Copper, 32 lbs.; zinc, 10 lbs.; lead, i lb. is ductile, more lead renders copper
Best Red Brass, for' fine Cast brittle. Between 8 to 1 and 2 to 1 ings.-Copper, 24 lbs.; zinc, 5 lbs.; is the limit of copper and lead allors. bismuth, i oz. Put in the bismuth All of these alloys are brittle when hot last before pouring off.
or merely warm. Rolled Brass. — 32 copper, 10 Equal parts of copper and silver and zinc, 1:5 tin.
2 per cent. of arsenic form an alloy Common Brass, for Castings.-- similar to silver, a little harder, how20 copper, 1.25 zinc, 2.5 tin.
ever, but of almost equal tenacity and Hard' Brass, for Casting.–25 malleability. Antimony imparts a peparts copper, 2 zinc, 4.5 tin.
culiar beautiful red colour to copper, Brass Melting.–The best plan varying from rose-red in a little copper of smelting brass is to melt the copper and much antimony, to crimson or in a black-lead crucible first, dry and violet when equal parts of both metals cool the zinc as much as possible and are melted together. immerse the whole of the zinc into the Hardening for Britannia.copper when the latter is not hotter (To be mixed separately from the other than barely to continue fluid. Drop a | ingredients.)-Copper, 2 lbs.; tin, 1 lb. piece of borax the size of a walnut into Good Britannia Metal.-Tin, the pot. When the surface of the hot | 150 lbs.; copper, 3 lbs.; antimony, metal is covered by fine charcoal, or 10 lbs. borax, which is prevented by renewal Britannia Metal, 2nd quality.from burning, the smallest loss of zinc Tin, 140 lbs.; copper, 3 lbs.; antimony, is sustained.
9 lbs. The melting together of tin and cop BRITANNIA METAL, for Casting. per is less difficult than that of zinc Tin, 210 lbs.; copper, 4 lbs.; antiand copper, because tin is not so liable mony, 12 lbs. to evaporate as zinc, and little metal is BRITANNIA METAL, for Spinning.lost. The appearance of the alloy may Tin, 100 lbs.; Britannia hardening, be improved by covering the melted | 4 lbs.; antimony, 4 lbs. metal with about one per cent. of dried BRITANNIA METAL, for Registers. potash; or, better still, a mixture of Tin, 100 lbs.; hardening, 8 lbs.; antipotash and soda. This flux has a re- | mony, 8 lbs.