« AnteriorContinuar »
To Renew Manuscripts. - | 4 lbs. of copper, 12 lbs. best quality Take a hair pencil and wash the part | Banca tin, 8 lbs. regulus of antimony, that has been effaced with a solution of and 12 lbs. more of tin while the comprussiate of potash in water, and the position is in a melted state. Pour the writing will again appear if the paper antimony into the tin, then mix with nas not been destroyed.
the copper away from the fire in a Uniting Parchment to Paper, separate pot. or Wood.—The surface of the parch In melting 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 above composition is called of parchment are to be joined, both “hardening." For lining the boxes, 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. Thus the protogether. Another way is to put a thin portions for lining metal are, 4 lbs. of piece of paper between the surfaces of copper, 8 lbs. of regulus 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 lined, having been culty be separated. Glue and flour cast with a recess for the lining, is to paste are best adapted for uuiting sur le nicely fitted 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 half 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 clay 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 salturpentine. If required to take water ammoniac, and then immerse in melted colour, it must be washed over 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 have 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 silver turpentine, equal parts; proceed with colour. Cool it gradually in water, each sheet similarly, and dry them on then take the former, to which the 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 melt, lay 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, giving consisting of 2 oz. of tallow, oz. pow- it a head, so that as it shrinks it will dered black-lead, pint of linseed oil, | 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 is 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
remove 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 1 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. 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 object 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, 1 lb. is ductile, more lead renders copper
Best Red Brass, for fine Cast brittle. Between 8 to 1 and 2 to 1 ongs.-Copper, 24 lbs.; zinc, 5 lbs.; is the limit of copper and lead alloys. bismuth, 1 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 Auid. 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.
BEST BRITANNIA, for Spouts.—Tin, GERMAN SILVER, for Bells and 140 lbs. ; copper, 3 lbs. ; antimony, other Castings.--Copper, 60 lbs.; zinc, 6 lbs.
20 lbs.; nickel, 20 lbs ; lead, 3 lbs.; BEST BRITANNIA, for Spoons.—Tin, iron (that of tin plate being best), 2 lbs. 100 lbs.; hardening, 5 lbs.; antimony, In melting the alloy for German sil10 lbs.
ver it is difficult to combine a definite BEST BRITANNIA, for Handles. proportion of zinc with the compound Tin, 140 lbs.; copper, 2 lbs.; anti of nickel and copper previously premony, 5 lbs.
pared. In fusing the three metals BEST BRITANNIA, for Lamps, Pil together there is always a loss of zinc lars, and Spouts.—Tin, 300 lbs.; cop by volatilization, which may be lessened per, 4 lbs.; antimony, 15 lbs.
by placing it beneath the copper in the BRITANNIA, for Casting. — Tin, crucible. The best method is to mix 100 lbs.; hardening, 5 lbs.; antimony, the copper and nickel, both in grains 5 lbs.
first, place them, thus mixed, in the Lining Metal, for Boxes of Rail crucible, when melted add the zinc and road Cars.—Mix tin, 24 lbs. ; copper, a piece of borax the size of a walnut. 4 lbs.; antimony, 8 lbs. (for a harden The zinc will gradually dissolve in the ing); then add tin, 72 lbs.
fluid copper, and the heat may be raised Bronze Metal. - (1.) Copper, as their fluidity increases. In this in7 lbs.; zinc, 3 lbs.; tin, 2 lbs. (2.) stance, as in all others of forming Copper, 1 lb.; zinc, 12 lbs.; tin, 8 lbs. alloys, it is profitable to mix the oxides
Artificial Gold. -- Pure copper, of the various metals together, and 100 parts; zinc, or preferably tin, 17 reduce them under the protection of a parts; magnesia, 6 parts; sal-ammoniac, suitable flux. The metal nickel can be 3.6 parts; quicklime, 1.8 part; tartar produced only from pure oxide of of commerce, 9 parts. The copper is nickel; and, as purity of the alloy is first melted, then the magnesia, sal essential to good quality, the common ammoniac, lime, and tartar, are then commercial zinc is not sufficiently pure added, separately and by degrees, in for forming argentan. Copper cannot the form of powder; the whole is now well be used in the form of oxide, but briskly stirred for about half an hour, grain copper or wire-scraps will serve so as to mix thoroughly; and then the equally as weii. zinc is added in small grains by throw Imitation of Silver.— Tin, ing it on the surface and stirring till it 3 oz.; copper, 4 lbs. is entirely fused; the crucible is then | Pinchbeck.-Copper, 5 lbs.; zinc, covered, and the fusion maintained for 1 lb. about 35 minutes. The surface is then Tombac.—Copper, 16 lbs. ; tin, skimmed and the alloy is ready for 1 lb.; zinc, 1 lb. casting. It has a fine grain, is malle Red Tombac.-Copper, 10 lbs.; alle, and takes a splendid polish. Does zinc, 1 lb. not corrode readily, and for many pur
Stereotype Metal.-1 tin; 1 poses is an excellent substitute for gold. antimony; 4 lead. In using stereotype When tarnished, its brilliancy can be metal, brush the type with plumbago restored by a little acidulated water.
German Silver, First Quality for in a frame, and take a cast with plaster Casting.–Coppei, 50 lbs.; zinc, 25 lbs.; of Paris. The cast is dried in a very nickel, 25 lbs.
hot oven, placed face downwards upon GERMAN SILVER, Second Quality for a flat plate of iron; this plate is laid Casting.–Copper, 50 lbs. ; zinc, 20 lbs. ; in a tray or pan of iron, having a lid nickel (best pulverized), 10 lbs.
securely fastened, and furnished with a GERMAN SILVER, for Rolling.–Cop hole at each corner. Dip the tray in per, 60 lbs.; zinc, 20 lbs. ; nickel, 25 lbs. the fluid metal, which will flow in ai Used for spoons, forks, and table ware. the four corners. When the tray is je
inind, during the inking, free from all These principles do not apply to horithought of accuracy of the construction, zostal views, as maps of surveys, where that it may be given to excellence in the title may be wherever the shape of execution. Therefore, the whole of the the plot affords the best place. pencil-construction should be most accu One quite essential element of beauty iately made in the finest faint lines with in a title is its arrangement, or the form a hard pencil.
of its outline as a whole. It should Finishing a Drawing. embrace such variations in the length While 6 Finish a drawing without any of its lines of letters that the curve error or defect,” should be the draughts formed by joining the extremities of man's best motto, he should never be in those lines would be a simple and haste to reject a damaged drawing, but graceful one, having also a marked should exercise his ingenuity to see how variety of form. Also the greatest far injuries done to it may be remedied. length of the title should generally be “ Never lose a drawing once begun," horizontal; or its proportions, as a should be his second motto; and since whole, like those of the border of the prevention is easier and better than drawing. cure, let him always work calmly, in When the occupation of the paper spect all instruments, hands, and sleeves, affords only narrow blank spaces lying that may touch a drawing, before com lengthwise of the paper, the title looks mencing an operation ; let the paper, well mostly on a single line at the instruments, and person be kept clean, bottom, the principal words being in and when considerable time is to be the middle, and the subordinate ones at spent upon a portion of the paper, let the two sides. the remainder be covered with waste Moreover, horizontal lines should paper, pasted to one edge of the board. prevail in the direction of the lines of
For the final cleaning of the drawing, words in the title. Indeed, the title stale bread, or the old-fashioned black may be arranged wholly on horizontal india-rubber, if not sticky, is good ; lines with good effect, though an arched hut, aside from the carelessness of ever or bow-shaped curve for the principal allowing a drawing to get very dirty, words may be adopted when the drawany fine drawing will be injured, more ing includes some conspicuous arching or less, by any means of removing a lines. considerable quantity of dirt from it. The size of the title should be app..
Another excellent means of prevent priate to that of the drawing. In paring injuries, which should be adopted ticular, the rule has been proposed that when the drawing is worked upon only the height of the largest letters in the at intervals, is to enclose the board, title should not exceed three-hundredths when not in use, in a bag of enamelled of the shorter side of the border. Also, cloth or other fine material.
the relative size of the different porLettering.-The title to a draw tions of the title should correspond to ing should answer distinctly the four their relative importance, the name of questions - What, Who, Where, and the object and its inventor being largest, When, What, including the use and and that of the draughtsman, his locascale; Who, both as to designer or in tion, and the date of his work being ventor, and draughtsman; Where, both considerably smaller. as to the place, institution, or office Geometrical drawings are most apwhere the drawing was made, and the propriately lettered with geometrical locality of the object drawn; and When. letters, which, when neatly made, always
If the drawing is perfectly symme look well. Any letters, however, havtrical, its title should have the same ing any kind of sharply-defined and axis of symmetry as the drewing. If precise form, as German text, are not the drawing is unsymmetrica., the title inappropriate to a geometrical drawing; may be at either of the lower corners. I but vagzely formed "rustic" or other free-hand letters are in bad taste on hand also; but should still be largely such drawings.
geometrical in its design, and should Letters should correspond in con represent a real border of substantial spicuousness or body of colour with the materials, corresponding to the subject rest of the drawing, not being obtrusive of the drawiag. Thus, the mouldings from great heaviness of solid black and oruaments should represent ornaoutline, or unobservable from excessive mental metallic castings, carvings in faintness. Also, violent contrasts of wood, mouldings in plaster, or scrolls heaviness among neighbouring portions and leaves of rolled metal; but garof the title should be avoided; thoughlands, tassels, and tendrils, &c., should there may be a gradual change, both of not be introduced. intensity and size, from the most to the The border to a geometrical drawing least important words of the title. should be like the drawing itself in be
This should, first of all, not exceed in ing executed with the drawing pen and elaborateness the draughtsman's ability brush, as well as with the mapping pen. to execute it with perfect neatness and Free-hand pen borders, representing the clearness. Then it should agree with products of the soil, with cornucopias, the character of the drawing. Plain little pen sketches of scenery, or similar and simple letters look best on a similar | agricultural or landscape devices, worked drawing, while a complicated and in as corner-pieces, are more appropriate highly-finished drawing may receive on topographical drawings. letters of more ornamental character. As to colour, primary colours should
Borders. For line drawings the not be largely introduced into the border should be a geometrical design, border; first, since they, when obtruin lines, with curved or angular corners, sive, are adapted to ruder or less imor with combinations of straight or pressible tastes than the secondary hues, curved lines, forming geometrical cor shades, and tints, which are more gratiner-pieces. These borders may vary in fying to delicate tastes; and secondly, complexity from a rectangular border from the impertinent conspicuousness in single lines to borders which, though which they may give to the border. geometrical, may be elaborate and ele Drawings which are shaded only in gant. Thus: à plate of varieties of sepia or ink, or any dark neutral tint, straight horizontal lines may have a may hi.ve the border done in the same, plain rectangular border; one including or in a dark complementary colour, oblique lines may include oblique lines Tinted ink drawings are best finished in the border, either as a little tuft in with a plain ink border. each corner, a truncated corner, or a Indian Ink is used for producing square set diagonally, &c. Plates em the finished lines of all kinds of geomebracing curve lines may have quarter trical drawing. Being free from acid, circle borders, either convex or concave it does not injure or corrode the steel inwards-of which the former have points of the instruments. The genuine most decision. Such plates may also ink, as it is imported from China, varies have little circles for corner-pieces. considerably in quality ; that which Borders may sometimes conform in a answers best for line drawing will wash pleasing manner to the general outline up the least when other colours are of a drawing. Thus, an arched bridge passed over it. This quality is ascermay have a semi-oval upper border and tained in the trade, but not with perfect a square-cornered border at the base certainty, by breaking off a small porof the drawing; and an ornamental tion. If it be of the right quality it device may crown the summit of the will show, when broken, a very bright Lorder.
and almost prismatic-coloured fracture. When the drawing is a shaded one, Indian ink should be used immediately containing, therefore, some free-hand after it is mixed; if re-dissolved it bework, the border may be partly free- | comes cloudy and irregular in tone,