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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
rtions and leaves of rolled "metal; but garof the title should be avoided; though lands, 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, and Deposits of every description, pp. 170 to 246 ; Photography, pp. 246 to 295; Inks, pp. 343 to 349; Silvering, pp. 206 and 335; Gilding, pp. 188 to 199; Solders, p. 364; Soap, pp. 372 to 386; Candles, p. 350; Veneering, pp. 411 to 414; Marble Working, pp. 386 to 393 ; Dyeing, Graining, and Staining Wood, pp. 414 to 426 ; interspersed with other matters far too numerous to mention.
As far as possible subjects at all allied in character, either in constitution or mode of working, have been grouped together; and in general, the main subject is indicated by a heading in bold clarendon type, branch-subjects by small capitals, and details by italics. The difficulty, however, of obtaining certain information just when it was wanted, has prevented the adoption of anything like an alphabetical or other concatenated arrangement of the subject matter; it is believed that no inconvenience will arise from this cause, as the index is very comprehensive.
Care has been exercised in cases where the practical operation connected with a receipt has been apart from the writer's experience, to have it verified by authority, and the aim throughout has been to render Workshop Receipts' a reliable handbook for all interested in Technological pursuits.
August 1, 1873.
Drawing Paper.-The following table contains the dimensions of every description of English drawing-paper.
20 by 15
For making detail drawings an in. ferior paper is used, termed Cartridge; this answers for line drawings, but it will not take colours or tints perfectly. Continuous cartridge paper is also much used for full-sized mechanical details, and some other purposes. It is made uniformly 53 inches wide, and may be had of any length by the yard, up to 300 yards.
For plans of considerable size, mounted paper is used, or the drawings are afterwards occasionally mounted on canvas or linen.
Mounting Drawings or Paper on Linen.-The linen or calico is first stretched by tacking it tightly on a frame or board. It is then thoroughly coated with strong size, and left until pearly dry. The sheet of paper to be mounted requires to be well covered with paste; this will be best if done twice, leaving the first coat about ten minutes to soak into the paper. After applying the second coat, place the paper on the linen and dab it all over with a clean cloth. Cut off when thoroughly dry.
To Fasten Paper on a Draw. ing Board.—The stretched irregular edges of the sheet of paper are cut off against a flat ruler, squaring it at the same time. The sheet of paper is laid upon the board the reverse side upwards
to that upon which the drawing is to be made. It is then damped over, first by passing a moist clean sponge, or wide brush, round the edges of the paper about an inch and a half on, and afterwards thoroughly damping the whole surface, except the edges. Other plans of damping answer equally well; it is only necessary to observe that the edges of the paper should not be quite so damp as the other part of the surface. After the paper is thoroughly damped, it is left until the wet gloss entirely disappears; it is then turned over and put in its position on the board. About half an inch of the edge of the paper is then turned up against a flat ruler, and a glue-brush with hot glue passed between the turned-up edge and the board ; the ruler is then drawn over the glued edge and pressed along.
If upon removing the ruler the paper is | found not to be thoroughly close, a
paper-knife or similar article passed over it will secure perfect contact. The next alljoining edge must be treated in like manner, and so on each consecutive edge, until all be secured. The contraction of the paper in drying should leave the surface quite flat and solid.
Cutting Pencils.-If the point is intended for sketching, it is cut equally from all sides, to produce a perfectly acute cone. If this be used for line drawing, the tip will be easily broken, or otherwise it soon wears thick ; thus, it is much better for line irawing to have a thin flat point. The general manner of proceeding is, first, to cut the pencil, from two sides only, with a long slope, so as to produce a kind of chisel-end, and afterwards to cut the other sides away only suficient to be able to round the first edge a little. A point cut in the manner described may be kept in good order for some time by
pointing the lead upon a small piece of | fine sandstone or fine glass-paper; this
will be less trouble thau the continual
application of the knife, which is always | Whenever the surface of the paper liable to break the extreme edge. is roughened by using the erasing knife,
Erasing Errors.-To erase Cum it should be rubbed down with some berland-lead pencil marks, native or hard and perfectly clean rounded inbottle india-rubber answers perfectly. strument. This, however, will not entirely erase Buying Drawing Instruany kind of German or other manufac | ments.- Persons with limited means tured pencil marks. What is found will find it better to procure good iubest for this purpose is fine vulcanized | struments separately of any respectable india-rubber; this, besides being a more maker, W. Stanley of Holborn for inpowerful eraser, has also the quality of stance, as they may be able to afford keeping clean, as it frets away with the them, than to purchase a complete set friction of rubbing, and presents a con- | of inferior instruments in a case. With tinually renewed surface to the drawing; an idea of economy, some will purchase the worn-off particles produce a kind of second-hand instruments, which genedust, easily swept away. Vulcanized rally leads to disappointment, from the rabber is also extremely useful for fact that inferior instruments are cleaning off drawings, as it will remove manufactured upon a large scale pur. any ordinary stain.
posely to be sold as second-hand to purFor erasing ink lines, the point of a chasers, principally from the country, penknife or erasing knife is commonly who are frequently both unacquainted used. A much better means is to em with the workmanship of the instruploy a piece of fine glass-paper, folded ments and of the system practised. several times, until it presents a round Inferior instruments will never wear edge; this leaves the surface of the satisfactorily, whereas those well made paper in much better order to draw improve by use, and attain a peculiar upon than it is left from knife erasures. working smoothness. The extra cost or Fine size applied with a brush will be purchasing the case and the nearly usefound convenient to prevent colour less rules, would, in many instances, be running.
equal to the difference between a good To produce finished drawings, it is and an inferior set of instruments necessary that no portion should be without the case. Instruments may be erased, otherwise the colour applied carefully preserved by merely rolling will be unequal in tone; thus, when them up in a piece of wash leather, highly-finished mechanical drawings leaving space between them that they are required, it is usual to draw an may not rub each other; or, what is original and to copy it, as mistakes are better, having some loops sewn on the almost certain to occur in delineating leather to slip each instrument sepaany new machine. Where sufficient | rately under. time cannot be given to draw and copy, Drawing Board.—The qualities a very good way is to take the surface a good drawing board should possess off the paper with fine glass-paper be are, an equal surface, which should be fore commencing the drawing; if this slightly rounded from the edges to the be done, the colour will flow equally centre, in order that the drawing paper over any erasure it may be necessary when stretched upon it may present a to make afterwards.
solid surface; and that the edges should Where ink lines are a little over the be perfectly straight, and at right intended mark, and it is difficult to | angles to each other. erase them without disfiguring other ! In Using a Drawing Pen, portions of the drawing, a little Chinese it should be held very nearly upright, white or flake-white, m.zed rather dry, between the thumb and first and second may be applied with a fine sable-brush; | fingers, the knuckles being bent, so this will render a small detect much that it may be held at right angles less perceptible than by erasure. | with the length of the hand. The handle should incline only a very little | two appear perfect, a third straight-say ten degrees. No ink should be edge is applied to each of the edges used except indian ink, rubbed up fresh already tested, and if that touch it in erery day upon a clean palette. Liquid all parts the edges are all perfect. It ink and other similar preparations are may be observed that the first two generally failures. The ink should be examined, although they touch permoderately thick, so that the pen when fectly, may be regular curves; but if slightly shaken will retain it a fifth of so, the third edge applied will detect an inch up the nibs. The pen is sup the curvature. plied by breathing between the nibs In Using the Plain Parallel before immersion in the ink, or by Rule, one of the rules is pressed means of a small camel-hair brush; the down firmly with the fingers, while the nibs will afterwards require to be other is moved by the centre stud to wiped, to prevent the ink' going upon the distances at which parallel lines the edge of the instrument to be drawn are required. Should the bars not exagainst. The edge used to direct the tend a sufficient distance for a required pen should in no instance be of less parallel line, one rule is held firmly, than a sixteenth of an inch in thick and the other shifted, alternately, until ness; a fourteenth of an inch is perhaps the distance is reached. the best. If the edge be very thin, it is Using Dividers or comalmost impossible to prevent the ink passes. It is considered best to place escaping upon it, with the great risk of the forefinger upon the head, and to its getting on to the drawing. Before move the legs with the second finger putting the pen away, it should be care and thumb. In dividing distances into fully wiped between the nibs by drawing equal parts, it is best to hold the dia piece of folded paper through them viders as much as possible by the head until they are dry and clean.
joint, after they are set to the required To Test the Accuracy of a dimensions; as by touching the legs Straight-edge.-Lay the straight they are liable to change, if the joint edge upon a stretched sheet of paper, moves softly as it should. In dividing placing weights upon it to hold it a line, it is better to move the dividers firmly; then draw a line against the alternately above and below the line edge with a needle in a holder, or a from each point of division, than to roll very fine hard pencil, held constantly them over continually in one direction, vertical, or at one angle to the paper, as it saves the shifting of the fingers being careful to use as slight pressure on the head of the dividers. In taking as possible. If the straight-edge be off distances with dividers, it is always then turned over to the reverse side of better, first to open them a little too the line, and a second line be produced wide, and afterwards close them to the in a similar manner to the first at point required, than set them by about the twentieth of an inch distance opening. from it, any inequalities in the edge Pencilling.--If a drawing could will appear by the differences of the be at once placed to the best advantage distances in various parts of the lines, on the paper, and surely made without which may be measured by spring mistake and with all its lines correctly dividers.
limited when first drawn, it might be Another method will be found to made in ink directly on the blank answer well if three straight-edges are paper. To avoid the errors inevitable at nand; this method is used in making in the first copy of any production, even the straight-edge. Two straight-edges when made by those most practised, are laid together upon a flat surface, drawings are first pencilled and then and the meeting edges examined to see inked. The whole theory of pencilling, if they touch in all parts, reversing then, is, to lay out correct tracks on them in every possible way. If these which the pen is to more, leaving the