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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.

ERNEST SPON.

AUGUST 1, 1873.

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Drawing Paper.—The following 1 to that upon which the dmwing is to table contains the dimensions of every | be made. It is then damped over, first description of English drawing-paper. by passing a moist clean sponge, or

inches. inches.

wide brush, round the edges of the Demy .. .. .. ...

paper about an inch and a half on, and

20 by 15 Medium

17

afterwards thoroughly damping the Royal .. .

whole surface, except the edges. Other Imperial

plans of damping answer equally well; Elephant .. 27 , 23

it is only necessary to observe that the Columbier .. ..

edges of the paper should not be quite Atlas . 33 26

so damp as the other part of the surDouble Elephant ..

face. After the paper is thoroughly Antiquarian .. 52, 29

damped, it is left until the wet gloss Emperor . ..

entirely disappears; it is then turned

over and put in its position on the For making detail drawings an in. board. About half an inch of the edge ferior paper is used, termed Cartridge; of the paper is then turned up against this answers for line drawings, but it a flat ruler, and a glue-brush with hot will not take colours or tints perfectly. glue passed between the turned-up edge Continuous cartridge paper is also much and the board ; the ruler is then drawn used for full-sized mechanical details, over the glued edge and pressed along. and some other purposes. It is made If upon removing the ruler the paper is uniformly 53 inches wide, and may be found not to be thoroughly close, a had of any length by the yard, up to paper-knife or similar article passed 300 yards.

over it will secure perfect contact. The For plans of considerable size, mounted next adjoining edje must be treated in paper is used, or the drawings are after like manner, and so on each consecutive wards occasionally mounted on canvas edge, until all be secured. The conor linen.

traction of the paper in drying should Mounting Drawings or Paper leave the surface quite flat and solid. on Linen.-The linen or calico is Cutting Pencils.-If the point is first stretched by tacking it tightly on intended for sketching, it is cut equally a frame or board. It is then thoroughly from all sides, to produce a perfectly coated with strong size, and left until acute cone. If this be used for line nearly dry. The sheet of paper to be drawing, the tip will be easily broken, mounted requires to be well covered or otherwise it soon wears thick ; thus, with paste; this will be best if done it is much better for line irawing to twice, leaving the first coat about ten have a thin flat point. The general minutes to soak into the paper. After manner of proceeding is, first, to cut applying the second coat, place the the pencil, from two sides only, with a paper on the linen and dab it all over long slope, so as to produce a kind of with a clean cloth. Cut off when chisel-end, and afterwards to cut the thoroughly dry.

other sides away only suficient to be To Fasten Paper on a Draw. able to round the first edge a little. A ing Board.—The stretched irregular point cut in the manner described may edges of the sheet of paper are cut off be kept in good order for some time by against a flat ruler, squaring it at the pointing the lead upon a small piece of same time. The sheet of paper is laid fine sandstone or fine glass-paper; this upon the board the reverse side upwards will be less trouble thau the continu

applicaticn 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 Instru. any kind of German or other manufac ments.- Persons with limited means tured pencil marks. What is found will find it better to procure good inbest for this purpose is fine vulcanized struments separately of any respectable india-l'ubber; 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 1 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 Landle 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 every 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 uess; 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 IPencilling.-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 hand; 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 unind, during the inking, free from all | These principles do not apply to horithought of accuracy of the construction, 1 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 “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 but, 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 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 drawing. 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. | but vagiely formed "rustic" or other

lines.

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