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stone, to close its pores and keep it moist., before a second is put in. When all the The stone is now washed with water, and soap is melted the ingredients are allowed the printing ink applied with rollers, as to continue burning till they are reduced in letterpress printing ; after which it is one-third in volume. The shellac is now passed, in the usual way, through the added, and as soon as it is melted the press, the processes of watering and ink- flame must be extinguished. It is often ing being repeated for every impression. necessary in the course of the operation If the work lis inclined to get smutty to extinguish the flame and take the a little vinegar or stale beer should be saucepan from the fire, to prevent the put into the water that is used to damp contents from boiling over; but if any the stone.
parts are not completely melted, they There is a mode of transferring draw- must be dissolved over the fire without ings made with the chemical ink on paper being again ignited. The black is now prepared with a composition of paste, to be added. When it is completely mixed isinglass, and gamboge, which, being the whole mass should be poured out on damped, laid on the stone and passed a marble slab, and a heavy weight laid through the press, leaves the drawing on upon it to render its texture fine. The the stone, and the process above described | utmost care and experience are required for preparing the stone and taking the in the making both the ink and chalk, impressions is carried into effect.
and even those who have had the greatest LITHOGRAPHIC STONES, TO PREPARE. practice often fail. Sometimes it is not -Stones are prepared for chalk drawings sufficiently burned, and when mixed with by rubbing two together, with a little water appears slimy: it must then be silver sand and water between them, remelted and burned a little more. Sometaking care to sift the sand to prevent times it is too much burned, by which any large grains from getting in, by which the greasy particles are more or less dethe surface would be scratched. The stroyed; in this case it must be remelted, upper stone is moved in small circles over and a little more soap and was added. the under one till the surface of each is This ink is for writing or pen-drawing sufficiently even, when they are washed, on the stone. The ink for transfers should and common yellow sand substituted for have a little more wax in it. the silver sand, by which means is pro LITHOGRAPHIC CHALK.—Common soap, cured a finer grain. They are then again | 14 oz. ; tallow, 2 oz.; virgin wax, 2} oz.; washed clean, and wiped dry. It will be shellac, 1 oz. ; lampblack, 1 oz. Mix as found that the upper stone is always of a for lithographic ink. finer grain than the under one. To pre LITHOGRAPHIC TRANSFER PAPER.pare stones for writing or ink drawings, Dissolve in water oz. gum tragacanth. they are rubbed with brown sand, washed, Strain and add 1 oz. of glue and if oz. of and powdered pumice - stone used in-gamboge. Then take 4 oz. French chalk, stead; the stones are again washed, and oz. old plaster of Paris, 1 oz, starch each polished separately with a fine piece powder, and sift through a fine sieve; of pumice - stone, or water Ayr-stone. grind up, with the gum, glue, and gamChalk can never be used on the stones boge; then add sufficient water to give it prepared in this manner. The same pro the consistence of oil, and apply with a cess is followed in order to clean a stone brush to thin sized paper. that has already been used.
TRANSFERRING. — The drawing or LITHOGRAPHIC INK.—Tallow, 2 oz.; writing made on the prepared side of the virgin wax, 2 oz.; shellac, 2 oz.; common transfer paper is wetted ou the back, and soap, 2 oz.; lampblack, } oz. The wax placed, face downwards, on the stone, and tallow are first put in an iron saucepan which must previously be very slightly with a cover, and heated till they ignite; warmed, say to about 125° F. Pass the whilst they are burning the soap must stone through the press four or five times, be thrown in in small pieces, one at a then damp the paper, and carefully retime, taking care that the first is melted | move it.
DRAWING ON STONE. — The subject the gum off with water. The lines on should first be traced on the stone in red, the stone will appear thicker than they great care being taken not to touch the will print. stone with the fingers. Or the drawing To Imitate Woodcuts on Stone.-Cover may be done by means of a black-lead with ink those parts meant to be black; pencil ; but this is objectionable, as it is scratch out the lights with an etching difficult to distinguish the line from that needle; the lines which come against a made by the chalk or ink. Then, having white background are best laid on with a rest to steady the hand, go over the a very fine brush and lithographic ink. drawing with the chalk, pressing it with | Inking Roller.–Fasten a smooth piece sufficient firmness to make it adhere to of leather round a wooden roller of the the stone. For flat tints, considerable required length. practice is necessary to secure an even Removing the Transfer.—The existing appearance, which is only to be obtained transfer is ground away by rubbing it by making a great many faint strokes with another piece of stone, putting sand over the required ground. Lights may between, like grinding flour between the sither be left, or, if very fine, can be millstones, using finer sand as it gradually scraped through the chalk with a scraper. wears away; then it is ground with If any part is made too dark, the chalk rotten-stone till of the requisite fineness must be picked off with a needle down to for the next transfer. the required strength.
Transferring from Copper to Stone. ETCHING-IN, FOR PRINTING ON STONE. In transferring from copper to stone use -Dilute one part of aquafortis with one prepared paper, that is, ordinary unsized hundred parts of water. Place the stone | paper, coated with a paste of starch, gumin a sloping position, then pour the solu- arabic, and alum. Take about 60 parts tion over it, letting it run to and fro until of starch, and mix with water to a it produces a slight effervescence. Then thinnish consistency over a fire; have wash the stone with water, and after-twenty parts of gum ready dissolved, wards pour weak gum water over it. The and also ten parts of alum dissolved ; acid, by destroying the alkali on the when the starch is well mixed, put in lithographic chalk, causes the stone to the gum and alum. While still hot, refuse the printing ink except where coat the paper with it in very even touched by the chalk; the gum water layers, dry, and smooth out. Take an fills up the pores of the stone, and thus impression from the copper with the prevents the lines of the drawing from transfer ink; lay the paper on the stone, spreading. When the stone is drawn on damp the back thoroughly with a sponge with ink, there must be a little more and water, and pass through the litho. acid used with the water than when the press. If all is right, the impression drawing is made with chalk. The roller | will be found transferred to the stone, charged with printing ink is then passed but it will of course require preparing in over the stone, which must not be too the usual manner. The great advantage wet, and the impression is taken as before gained is, that very many more impresdescribed.
sions may be printed from stone than ENGRAVING ON STONE.—The stone from a copper plate, and very much must be highly polished ; pour the solu quicker. tion of aquafortis and water over it, Engraving on Steel is the same as washing it off at once. When dry, cover copper-plate engraving, except in certain with gum water and lampblack ; let this modifications in the use of the acids; dry, then etch with a needle, as on copper. therefore, so far as the process is conIt is necessary to cut the surface of the cerned, no particular description is necesstone through the gum, the distinction sary; but the means employed for deof light and dark lines being obtained by carbonizing and recarbonizing first the the use of fine or broad-pointed needles. | steel plate, so as to reduce it to a proper Rub all over with linseed oil, and wash / state for being acted upon by the graving tool, must be explained. In order to diate space between the sides of the box decarbonate the surfaces of cast-steel and the plate may be about an inch, plates, by which they are rendered much Fill the box with the powdered charcoal, softer and fitter for receiving either and, having covered it with a well-fitted transferred or engraved designs, pure lid, let it be placed in a furnace similar to iron filings, divested of all foreign mat those used for melting brass, when the ters, are used. The stratum of decar- heat must be gradually increased until bonated steel should not be too thick the box is somewhat above a red heat; for transferring fine and delicate en | it must be allowed to remain in that gravings; for instance, not more than | state till all the evaporable matter is three times the depth of the engraving ; driven off from the charcoal; remove but for other purposes the surface of the the lid from the box, and immerse the steel may be decarbonated to any required plate in the powdered charcoal, taking thickness. To decarbonate it to a proper care to place it so that it may be surthickness for a fine engraving, it is to be rounded on all sides by a stratum of the exposed for four hours in a white heat, powder of nearly a uniform thickness. enclosed in a cast-iron box with a well-The lid being replaced, the box, with the closed lid. The sides of the box must be at plate, must remain in the degree of heat least three-quarters of an inch in thick- before described for from 3 to 4 hours, ness, and at least a thickness of half an according to the thickness of the plate inch of pure iron filings should cover or so exposed; 3 hours are sufficient for a surround the cast-steel surface to be de- | plate of an inch in thickness, and 5 carbonated. The box is allowed to cool hours when the steel is 11 inch in thickvery slowly, by shutting off all access of ness. After the plate has been exposed air to the furnace, and covering it with a to the fire for a sufficient length of time, layer of six or seven inches of fine cinders. take it from the box and immediately Each side of the steel plate must be plunge it into cold water. Here it is equally decarbonated, to prevent it from found by experience that the plates, springing or warping in hardening. The when plunged into cold water, are least safest way to heat the plates is to place liable to be warped or bent when they them in a vertical position. The best are held in a vertical position, and made steel is preferred to any other sort of to enter the water in the direction of steel for tbe purpose of making plates, their length. If a piece of steel, heated and more especially when such plates to a proper degree for hardening, be are intended to be decarbonated. The plunged into water, and suffered to resteel is decarbonated to render it suffi-| | main there until it becomes cold, it is ciently soft for receiving any impres- | found by experience to be very liable sion intended to be made thereon ; it is, to crack or break, and in many cases it therefore, necessary that, after any piece would be found too hard for the operaof steel has been so decarbonated, it tions it was intended to perform. It the should, previously to being printed from, steel cracks it is spoiled. Therefore, to be again carbonated, or reconverted into fit it for use, should it not be broken in steel capable of being hardened. In order hardening, it is the common practice to to effect this recarbonization or recon- heat the steel again, in order to reduce rersion into steel, the following process or lower its temper. The degree of heat is employed; a suitable quantity of to which it is now exposed determines leather is to be converted into charcoal, the future degree of hardness, or temper, by exposing it to a red heat in an iron and this is indicated by a change of colour retort antil most of the evaporable matter upon the surface of the steel. During is off the leather. The charcoal is reduced this heating a succession of shades is pruto a very fine powder ; then take a box duced, from a very pale straw colour to made of cast iron of sufficient dimension a very deep blue. It is found that, on to receive the plate which is to be recon- plunging the steel into cold water, and verted into steel, so as that the interme- allowing it to remain there no longer than is sufficient to lower the tempera-, a brown or such colour as may suit the ture of the steel to the same degree purpose required. The above is an old as that to which a hard piece of steel process and not generally used. Enmust be raised to temper it in the com graving on steel is effected nowadays by mon way, it not only produces the graving and etching like, copper ; using same degree of hardness in the steel, but, | for biting-in a mixture of 1 part pyrowhat is of much more importance, almost ligneous acid, 1 nitric acid, 3 water : run entirely does away with the risk of its off from the plate in less than a minute, cracking. The proper degree of tempera rinse in running water, and dry quickly. ture arrived at, after being plunged into Use stronger acid when a deeper tint is cold water, can only be learned by actual required. observation, as the workman must be Engraving Steel Cylinders. A cylinder guided entirely by the kind of hissing of very soft or decarbonized steel is made noise which the heated steel produces in to roll, under a great pressure, backward the water while cooling. From the and forward on the hardened engraved moment of its first being plunged into plate till the entire impression from the the water the varying sound will be engraving is seen on the cylinder in altoobserved ; and it is at a certain tone, relievo. The cylinder is then hardened before the noise ceases, that the effect to and made to roll again backward and forbe produced is known. As a guide, take ward on a copper or soft steel plate, a piece of steel which has already been whereby a perfect facsimile of the origihardened by remaining in the water till nal is produced of equal sharpness. cold, and by the common method of Etching.–The apparatus consists of again heating it, let it be brought to the copper plates, etching needles, hand-rest, pale yellow or straw colour, which indi- etching-ground dabber, oil-rubber, rottencates the desired temper of the steel stone, smoking taper, engraver's shade, plate to be hardened. By the above pro- bordering wax, stopping -out varnish, cess, as soon as the workman discovers tracing paper, and aquafortis. this colour to be produced, to dip the steel Ground.—The ground is composed of into water and attend carefully to the equal parts of asphaltum, Burgundyhissing which it occasions, he will then pitch, and beeswax; place them in an be able, with fewer experiments, to judge earthen pipkin in an oven, and melt. of the precise time at which the steel The mass must be kept stirred until well should be taken out. Immediately on incorporated. Pour the mixture into a withdrawing it from the water, the steel basin of cold water, and, when nearly plate must be laid upon or held over a cold, it should be pressed, and rolled with fire, and heated uniformly until its tem- the hand until all the water is discharged, perature is raised to that degree at which then make into a ball. Procure a piece a smoke is perceived to arise from the of worn silk, without holes ; double it; surface of the steel plate after having place the ball therein, and tie up the been rubbed with tallow; the steel plate ends with packthread, taking care that must then be again plunged into water, the double silk reaches well and tightly and kept there until the sound becomes over the ball; cut off the surplus silk, somewhat weaker than before. It is to be and let the knot remain for a hand-hold. taken out, and heated a second time to Dabber.—Take a piece of silk, twice the the same degree as before, and the third size of that for the ground ball; double time plunged into water till the sound it; place in it a ball of coarse wool well becomes again weaker than the last; ex picked out, about the size of a small posed the third time to the fire as before; 1 apple; tie it up in the same way as the and for the last time returned into the ball for the ground, and it is ready for use. water and cooled. After it is cooled Oil-Rubber. - An oil-rubber is made clean the surface of the steel plate by from a strip of woollen cloth, about 2 heating it over the fire. The temper inches wide, rolled up tightly, and bound must be finally reduced by bringing on lover with packthread or thin tape. With a sharp knife cut off one end, avoiding / wire into a half circle; bind it together the string, so that the surface may be with waxed string; lay it on tissue paper; quite flat. This is used for taking out cut away all but 'an inch round the stains, or polishing the plate, as in Fig. 46. wire: cover that I inch with paste, and FIG. 46.
turn it over the wire; when dry the shade is complete. Fasten a light string to the centre of the half-circle, and suspend it from the window-latch when in use. This shade must be placed in a forward position, sloping before the
plate, and the white light it produces Rotten-stone. — Take a piece of fine will enable the engraver to see the lines fannel, rather less than the silk which made by the etching needle. An equally covers the etching-ground ball; double effective shade may be made by covering it; place on it a small quantity of rotten- a light square wire frame with tissue stone, in powder, which tie up in a bag. paper, and supporting it with two struts. A small portion of fine whiting in the This frame can be made to rest at any lump should be also kept at hand. angle, upon the table immediately in
Smoking Taper, or Lamp.--For small front of the work. plates, procure a wax taper; uncoil it by Hand-Rest.—Any flat and thin piece degrees before the fire until it is all of wood will answer the purpose, which equally pliant; double it up in about six is to keep the hand clear of the plate lengths; give it one twist while warm, whilst at work. A good hand-rest may and turn it a few times before the fire, be made of a thin board raised above the that the pieces of taper may adhere to work upon side pieces of such a height each other; melt the wax at one end, so as to allow the plate to be freely moved that the wick is exposed ; see that all underneath the board. The front edge the cotton ends will light freely; care of the board may be faced with a strip should be taken to extinguish the cotton, of steel planed true when it serves as a or it will revive with the least draught, straight-edge. This arrangement will and may become dangerous. For large be found extremely handy. plates it is preferable to use an ordinary | Stopping - out Varnish. — Turpentine oil lamp mounted on gimbals; this ob varnish is superior, for several reasons, viates the inconvenience occasioned by to Brunswick black. the dripping of the tapers.
Turpentine Varnish.—Break small pieces Bordering Wax.— 3 oz. of resin, 2 oz. of resin into a phial; pour over spirits of of beeswax, and such a quantity of sweet turpentine to about twice the height of the oil as will soften the mixture to fancy. resin. Place the bottle in a small saucepan Procure an earthen pipkin ; place in the of water on the hob, near enough to the bottom oz. or more of sweet oil ; add the fire to make and keep the water hot; resin and beeswax, broken in small pieces; 1 place a cork lightly in the mouth of the when melted work the ingredients well | bottle, as the mixture will require to be together with a stick until thoroughly in- shaken occasionally. Pour a small portion corporated ; then pour into a basin of cold of this mixture into a small pot, with a water; as it gets cold, work it well with little lampblack added to give it a colour, the hands by pulling out into lengths and well mixed. This last is necessary to and doubling it together again ; the more prevent lumps; it may be done by workit is worked the better it will be for use. ing the mixture well together with the Should it turn out brittle, return it camel-hair pencil. This is a good stopbroken to the pipkin, and add more oil ; 1 ping-out varnish. With this varnish go work it well together as before, pour it over the border or margin of your plate; into water, and work it again with the do this when about to put it away, and hands.
the varnish will become hard by being Engraver's Shade. - Bend a piece of left a night to set. When biting-in