magic lanternFig. 9.
Fig. 9.
The method of charging the apparatus is as follows. Put into the retort about a pound and a half of oxygen mixture; pour into the purifier a sufficient quantity of water to about two-thirds fill it. Place the retort on a clear but not fierce fire, or over a gas furnace, and unite it to thelongtube of the purifier (B). Attach theshortpipe from the purifier to the gas-bag, and open all the taps, so that there may be a free passage-way from the retort to the bag. In a few minutes the gas will be given off, and will manifest itself by rising in bubbles through the water in the purifier. If a fierce fire be employed, the gas will be given off with undue rapidity and will pass through the purifier in volumes, so that it only becomes partially washed. A rapid but regular succession of gas is most to be desired. Should the gas come off with great violence, the retort should be lifted from the fire without disarranging the apparatus, and when the excessive rapidity is moderated it can be replaced. It is not, however, desirable to remove the retort from the fire if it can be avoided, for it not unfrequently happens that when the retort cools down, with only partially decomposed material in it, waste is the consequence, as it is not quite easy to re-establish the decomposing process. When the gas has entirely come off—which may be known by the cessation of the bubbles in the purifier—the top of the bag should be closed, the retort taken from the fire, detached from the purifier, and stood aside to cool. When cold, the residuum may be readily washed out with water, and when dry, the retort is ready for use again. The purifier should be emptied and washed out also. Always blow through the flexible tubes leading from the retort to the purifier, and wash out the metal tube of the retort in order to remove any solid material that may have been deposited there from the gas.
There has recently been manufactured a very neat oxygen gas-generator and gas-burner combined. The inventor proposes to prepare the oxygen in the room where the exhibition is taking place, and while using the lanterns. But as this apparatus would be very difficult to manipulate with, even by an experienced operator, it cannot be recommended for general use.
With regard to the hydrogen gas, it is always best to use the ordinary house gas, or if that cannot be obtained, to use the oxycalcium lamp, as the preparation of the pure hydrogen gas is troublesome, and not quite free from danger.
The preparation of magic-lantern slides for home use (although, perhaps, not equalling the bought ones in quality) is a great source of pleasure, and a few hints on this part of our subject will probably be acceptable. A number of very amusing slides may be made by cutting grotesque or other figures out of black paper, and pasting them on glass slips, and after the pictures are dry, giving a little detail by slashing the picture with a sharp penknife in places where needed. If these figuresbe first drawn on tissue paper, coloured, and then cut out, the effect is still more pleasing. Or, if preferred, sheets of these figures in black can be bought, and thus the trouble of drawing them will be saved.
A very efficient set of astronomical slides may be constructed out of blackened cardboard with the aid of a few punches, some different-sized needles, and some of the coloured gelatine bon-bons. Having cut the card of a size suitable for the lantern, and marked on it a circle of the same diameter as the lantern condenser, prick holes in the card by aid of the needles, so as to represent the principal constellations and nebulæ, illustrations of which will be found in most works on astronomy. The relative positions of the planets may be shown by punching holes in the cardboard and covering them over with gelatine. When the holes are punched, the orbits may be traced by a very minute row of holes, pricked with a fine needle, the circles having first been marked with a pair of compasses.
For larger diagrams representing the planets singly, a sharp penknife and a pair of compasses would, combined with a steady hand, produce wonders.
The painting of magic-lantern slides on glass is a rather more difficult task, and some knowledge of the rules of the art of painting in general will be found most useful. The colours and brushes to be used are sold in boxes, and the number of colours can be readily increased by mixing. The following articles may be considered necessaries. Easel, glass to paint on, pencils, dabbers, etching-needles, fixing varnish, and the following colours: Blue, Nos. 1 and 2, crimson, amber, brown, mauve, black, light green, dark green, orange, purple, and scarlet. Having obtained these articles, proceed as follows. Make a drawing of the picture required, of the right size, on white paper, and place this under the glass upon which the picture is to be painted. The outline is then to be traced on the glass in Indian ink with a fine pen. This part of the work, however, can be dispensed with if the glasses be bought having pictures already outlined on them. If the subject of the picture be a landscape, the outlined glass is to be turned upside down, and the sky filled in first, commencing at the horizon with a pale tint, which is to be increased in density as the edge of the picture is approached. To remove any superfluous colour, a dabber is used.
When this colour has dried, the other parts of the picture are painted in succession with appropriate tints, warm tints being employed for the objects in the foreground, neutral or cool tints for the background.
This having been done, the picture has then to be coated with the fixing varnish, either using a brush or pouring it on as a photographer would do; or, when it has covered the surface, allowing it to run back into the bottle from one of the corners. The varnish is then allowed to dry, after which the picture is again to be examined, the shadows of the buildings and the trees are to be filled in, and the colour strengthened where the picture seems to need it. Snow and moonlight effects are produced chiefly by removing the colour in places by means of a knife and needle-point.
The rules given above apply also to the colouring of photographs for the magic lantern.
If you were to go to a shop to buy a lantern like the one I am going to describe, it would cost thirty-five shillings, but you will be able to make it for fourteen or fifteen. I will tell you what mine cost me, including the slides. The lantern cost me fifteen shillings.
With these colours and glass I have painted 250 slides, which to buy would cost two shillings each, and the cost of lantern and 250 slides would thus be:—
making a clear saving of £25.
Besides this, you have the double pleasure of making the lantern and painting the slides, and showing it as your own work. The picture shown by this lantern will be nine or ten feet in diameter, and will be large enough to show full-sized slides if you should at any time buy any. If you do buy, I should recommend the uncoloured photographs (1s.6d.each), to be got at all shops where they sell lanterns. By making two of these lanterns you can use them for dissolving views, which is by far the best way to exhibit the slides. Many brilliant effects can be obtained with two lanterns that it would be impossible to do with a single lantern. I should certainly advise you to try this. Both lanterns can be made at the same time; the directions for one will do for both. But we must get on with our description.
First of all get a carpenter to cut you a deal board, free of knots, six feet six inches long, nine inches wide, and half an inch thick. This must be planed smooth on both sides. If you have a plane, do this yourself. Now with a fine saw cut four pieces off the board, each twelve inches long, and two pieces nine inches long.These are to make the body of the lantern with. Take two of the long pieces and the two short pieces, and reduce the width to six inches. These will be the top, bottom, back, and front of the lantern. Now you must put the pieces together by dovetailing; or you had better get the carpenter to do this for you, as unless you are used to this work you would be sure to make a mess of it. Do not glue the pieces together yet. Take the piece of wood that is to serve for the top, and draw lines with a pencil from opposite corners, likeFig. 1. Now with a pair of compasses, open one inch and a half apart, put one point at the point where the two lines cross each other, and mark a circle with the other point. This circle must be cut out either with a keyhole saw or with a gouge, smoothing off with a rough file.
magic lanternFig. 1.magic lanternFig. 3.
magic lanternFig. 1.
Fig. 1.
magic lanternFig. 3.
Fig. 3.
magic lanternFig. 2.
Fig. 2.
Now take the piece of wood that is to be used for the front of the lantern and draw a pencil line across it, two inches from the top end, and then cross the other part with pencil lines (Fig. 2), as you did the top, and with the compasses open an inch and three-quarters make a circle as before and cut it out. Now take the piece of wood to be used for the right side of the lantern and mark it thus (Fig. 3). Draw lines across each end two inches from the edges, and along the side one inch and a half from the edges. Cut out the middle portion evenly up to the lines. This will form the door, and if you have cut the piece out with a keyhole saw it will do to be fastened on with hinges. If not, you must make another piece for the door. Now, round the bottom of the two sides and back bore holes with a half-inch centrebit. These holes must be one inch and a half from the centre of the hole to the edge of the wood. Three in the back piece and four in each side will be enough. These holes are to supply air for the lamp. Now you will want some sheet tin to line the lantern with. This you must buy. Get two and a half sheets of thin, and two and a half of very stout. The thin will be threepence each, the stout sixpence each. Cut pieces from the thin tin to line the lantern with—two pieces eight inches by ten inches, two pieces five by eight, one piece five by ten, and one piece five by eleven. Punch holes all round each of these pieces. This can be done with the sharp end of a file. Put the tin in its place on the top, front, and right side, and mark on it, through the holes, their exact size, and cut the tin away a little larger than the holes. Now you can put the linings in their places and fasten on with small tacks. Those used by upholsterers are the best. The tin at sides, back, and front, is cut short, so as not to cover the holes at the bottom. The tin can be easily cut with a large pair of scissors. The door must be lined with tin. When all the parts are lined youcan glue the joints and put the body together, fastening with small brads. This can now be put on one side to dry and set firm, as we shall next set to work to make the stage and nozzle.
Before you can do so you must get your lenses and reflector. These will cost you more than any other part of the lantern twice over. The lenses will be 10s.6d., and the reflector 2s.Ask for, or write for, a pair of lenses for No. 6Alantern, three and a half inches, and a four-inch reflector. First of all we must set the lenses. Take the largest, and cut a strip of thin tin half an inch wide, and long enough to go right round the lens and lap an eighth of an inch. The best way to measure this is with a piece of paper, cut into a strip and passed round the lens, and cut to the exact length of the circumference of it. Place this paper on your tin and cut the latter an eighth of an inch longer than the paper. You must now solder the ends of this strip of tin together to make a ring. To do this you must have a soldering bit, and as this is always useful you had better buy one.
Take a small piece of clean tin, put on it two or three drops of chloride of zinc, and in this put a small piece of solder. Put the bit in the fire to get hot—but not red-hot. When hot, rub the point with a file till it is bright, and put it on the solder, which will immediately flow and cover the point of the bit. This is called tinning the bit, and must always be done when the bit gets red-hot, as that burns off the tinning.
Put your bit in the fire to get hot, and while it is there bring the ends of the tin strip together so that they lap an eighth of an inch. Dip a camel-hair brush in the liquid and rub the joint between the lapping and an eighth of an inch outside. Put a small piece of solder at the top of the joint. Now if the bit be hot enough put it on the solder, and, as soon as it has melted it, draw it slowly along the joint, and the solder will flow after it and make a firm joint. In making joints like this, the parts of the tin lapping must touch each other closely. When the joint is cold, take a small hammer and turn in one edge all round a sixteenth of an inch. This will be easily done by gently tapping the edge with the hammer over a piece of wood, such as a toothpowder-box or ribbon-roller. In doing this you must be careful not to put the band out of the round. When this is done, put the lens inside, resting on the turned-in part. Now get a piece of brass wire a sixteenth of an inch thick, and about a quarter of an inch less in length than the tin strip was, and bend it into a ring, but do not fasten the ends together. Put the ring inside the band against the lens, and it will spring against the sides and hold the lens firmly in its place. This lens, with its setting, is to be placed inside the lantern in the large hole in the front of it, with the lens towards the back of the lantern.
Now we must set the other lens. Take a piece of the thin tin two and a half inches wide, and long enough to go round the lens and lap an eighth of an inch. In cutting this you must be careful to keep the sides and angles square, or it will not be true when made into a tube. Now get a roller for silks about an inch and a half thick and roll the tin round it to make a tube by bringing the shortest edges together. Be careful to make the tube nice and round and smooth; lap the edges an eighth of an inch, and solder them together as you did the other tube. Turn in one edge all round a sixteenth of an inch, put the lens inside, resting on theturned-in part, and fix it with a wire ring. Now take a strip of tin an inch wide and long enough to go round this last tube and lap an eighth of an inch. Bring the edges together, lapping an eighth of an inch, and solder.
This is the tube to be fixed in the nozzle, for the front lens tube to slide in, to regulate the focus. Round this little tube, half an inch from the edge, mark a line.
Now we will get on with the stage. For this you will use your stout tin. Take one of the plates and mark on it a piece five inches by eight, being very careful to make it quite square at the corners. Cut this piece of tin out. Now draw a line across each end at half an inch from the edge, and another line an inch and a half from the edge (Fig. 4). Cross the middle portion by lines drawn from opposite corners, and with your compasses mark a circle three inches and a half in diameter. Cut out this circular portion, being careful not to bend the plate; but if you do you must straighten it again with a piece of wood, bend the ends down along the inner line till they are at right angles with the other part of the plate (Fig. 5). Now bend the tin outwards along the other lines till it is at right angles to the other part (Fig. 6). Punch two holes about an eighth of an inch wide in each of the turned-out parts. These holes are to screw the stage to the lantern by. Next you must get two pieces of clock-spring about a quarter of an inch wide and four inches and seven-eighths long. Bend them into bows about an inch high, and turn the ends outwards a little (Fig. 7). Solder these into the inside of the stage by the middle at the top and bottom of the hole (Fig. 8). Cut another piece of tin seven inches and seven-eighths by seven inches and a quarter, and cut a circular hole in the middle four inches in diameter. Mark a line across each end an inch and an eighth from the edge, and bend the plate at right angles at each end.This is to make the spring clip to hold the slides; it is put inside the stage, resting on the springs, and with the turned-out parts outside (Fig. 9).
In cutting the tin for the next part, you must be careful to keep the sides and angles square; also in bending it into a tube and soldering it. Mark out on your tin plate (stout tin) a piece eleven and a quarter inches long and four and one-eighth inches wide, turn this into a tube by bringing the shortest edges together round a bottle, lap them a quarter of an inch, and solder the joint; now very carefully turn out one edge all round, one-eighth of an inch, being careful not to disturb the round. This can be done against the edge of a flat-iron by gently tapping with your small hammer. Cut out a circular piece of tin three inches and a half in diameter, and in the centre cut out a circular hole exactly the size of the small tube the lens-tube slides in; pass this tube half way through this hole, and solder it in, being careful that it is squarely in; now put this piece into the end of the large tube, not the turned-out end, so that the side that is soldered is inwards, and solder this on the inside of the tube. Next solder this tube, which is the nozzle of the lantern, on to the outside of the stage, being careful that the holes in the stage and tube correspond. You had better strengthen the stage by soldering corner pieces in where the turn-out parts are (Fig. 10). Now the stage and nozzle is ready to be screwed into its place on the front of the lantern, being careful that the centre of the holes are all in the same straight line; but before screwing it on, all the tin visible must be blackened with dull black paint, which I will tell you how to make at the end of this section. The inside of the lantern must also be painted with this black paint, as well as the inside of the front lens-tube. In this tube there must be what is called a diaphragm. To make this, take a piece of thin tin an inch and a quarter wide, and long enough to go round the inside of the lens-tube; solder the edges together, and close the end with a circular piece of tin with a circular hole in the middle of it a little less than half an inch in diameter. Blacken this and push it into the tube, so that the little hole is about half-way in. The lens-tube is to be pushed into the nozzle with the lens inside. To make the chimney, take a piece of tin six inches wide and nine inches and three-quarters long, bend it into a tube, and lap a full eighth of an inch; solder up the joint; then cut four notches in the top about three-quarters of an inch deep (Fig. 11).
magic lanternFig. 10.magic lanternFig. 11.
magic lanternFig. 10.
Fig. 10.
magic lanternFig. 11.
Fig. 11.
magic lanternFig. 12.
Fig. 12.
Now mark on a piece of tin a circle four inches and a quarter radius, or eight and a half inches wide; cut this circle out. Now cut out a quarter of the circle (Fig. 12), bring the cut edges together, lap them a little, and solder the joint, so thatit makes a small tin cone (Fig. 13). Put this on to the four points on the top of the chimney-tube, and solder those points into it securely, and your chimney will be finished and look likeFig. 14. This must be pushed into the hole at the top of the lantern.
magic lanternFig. 13.magic lanternFig. 14.magic lanternFig. 15.magic lanternFig. 16.
magic lanternFig. 13.magic lanternFig. 14.
magic lanternFig. 13.
Fig. 13.
magic lanternFig. 14.
Fig. 14.
magic lanternFig. 15.magic lanternFig. 16.
magic lanternFig. 15.
Fig. 15.
magic lanternFig. 16.
Fig. 16.
Now for the lamp, and your lantern will be finished. You had better make this, as it would cost you 10s.6d.to buy, and you have nearly all the materials required. Cut a piece of stout tin nine inches and three quarters long and three inches and three quarters broad; make it into a tube by joining the short edges together, lapping them a little, about an eighth of an inch, and soldering the joint. For the bottom cut a piece of tin round, the exact size to fit tightly into the tube; in the middle of this cut a circular hole three-quarters of an inch in diameter, solder this in the lamp so that it is half an inch from the bottom end, and then cut the half-inch that projects like you did the top of the chimney. Now make a tube of tin to fit the hole in the bottom, and long enough to come level with the top of the lamp; solder this up, and into its place in the lamp (Fig. 15). Next you must get a short piece of brass curtain-rod that will just fit tightly over this last tube and be the same length. In this brass tube you must cut a spiral slot, running from top to bottom, and going once round. The slot is to be cut quite through the brass (Fig. 16). The best way to do this is to cut a piece of wood, about eight inches long, and thick enough to fit very tightly in the brass tube; then with a sharp file make your cut. The cut is to be about one-sixteenth of an inch wide. Now push this brass tube on to the tube in the lamp, and fix it by pressing the brass in a little.
The next thing to make is the wick-carrier. Make a short tube of tin three-fourteenths of an inch long, and to fit easily over the brass tube; round the bottom of this short tube put a band of stout tin one-fourth of an inch wide; through this band drill a hole one-sixteenth of an inch, and solder a sixteenth-of-an-inch wire through it, so that it projects one-eighth of an inch inwards, and one-eighth of an inch outwards. This little wick-carrier must be notched with a penknife (Fig. 17), so that it is covered with little points directed downwards; these points are to catch in the wick and hold it firmly.
magic lanternFig. 17.
Fig. 17.
magic lanternFig. 18.magic lanternFig. 19.
magic lanternFig. 18.
Fig. 18.
magic lanternFig. 19.
Fig. 19.
If this wick-carrier is put on the brass tube in the lamp, with the inside point in the spiral slot, as it descends it will turn to the left, and as it is lifted up it will turn to the right; consequently if it is turned to the right or left, it will ascend or descend, according to the way it is turned. To turn this wick-carrier we must have the following contrivance: Cut out a circular piece of stout tin that will fit easily into the lamp, and in the centre cut out a circular hole that will allow the wick-carrier to pass easily through it. At one side of this circular hole cut a little slot one-eighth of an inch each way (Fig. 18). Next make a tube of tin that will fit inside this hole, and will let the carrier pass freely up and down inside, but the edges of the tin must not be joined, but be an eighth of an inch apart. Solder this tube in its place in the circular tin, projecting through about a quarter of an inch, and so that the opening down the side of the tube corresponds with the square slot in the top. Solder a band of tin one-eighth of an inch wide all round the bottom of this tube to keep it firm (Fig. 19). Punch a hole in the top about a quarter of an inch from the edge, and fix a one-sixteenth wire in it about half an inch long.
magic lanternFig. 20.
Fig. 20.
Put this tube over the brass tube, so that the slot at top corresponds with the top of the spiral slot. Put the wick-carrier in its place, with the inner point in the spiral, and the outer point in the slot in the tube; and by turning the top to right or left the wick-carrier will ascend or descend, and, when the wick is fixed to it, will raise or lower the wick. To turn this top something more is wanted—that is, a movable top to carry the lamp-glass; this can be made to turn the movable top to raise the wick-carrier. For this you must get a piece of sheet-brass or copper—brass will look best, but copper is easiest worked. Whichever you decide upon, it must be a circular piece three and a half inches in diameter, and less than one-sixteenth of an inch thick. This copper is to be worked into the shape of a felt hat, with a crown three-quarters of an inch high, and one and a half wide. To do this you must make a block of hard oak wood six inches square and three inches thick; cut a hole in the middle the shape and size of the crown of the hat; this is to be like half a ball (Fig. 20).
magic lanternFig. 21.magic lanternFig. 22.
magic lanternFig. 21.
Fig. 21.
magic lanternFig. 22.
Fig. 22.
Now make another block two inches thick and six inches square, and bore a hole in each corner to screw the two blocks together by with four-inch screws. Make a hole right through the top block one inch and a half wide. Now make your copper red-hot and chill it in cold water—this will soften it; put it on the lower block with the centre of the copper exactly over the centre of the hole in the block, place the top block on the copper, and screw the two blocks together as tightly as you can. Now make a piece of oak three and a half inches long, and one inch and three-eighths thick, into a roller, and round one end. Put the rounded end in thehole, resting on the copper, and strike it repeatedly with a heavy hammer or mallet. This will drive the copper into the hollow in the bottom block. You must make the copper soft by making it red-hot repeatedly, and you will find that it will be easily worked into the hollow. As soon as it is forced quite into the hollow in the lower block you must unscrew the two blocks and finish the fitting by hammering with a round-faced hammer. Your copper will now be likeFig. 21. Now you must file off the top of the crown, so as to make a hole at the top three-quarters of an inch in diameter, likeFig. 22.
magic lanternFig. 23.magic lanternFig. 24.
magic lanternFig. 23.
Fig. 23.
magic lanternFig. 24.
Fig. 24.
Next you must cut the brim likeFig. 23, making three projections three-eighths of an inch wide, and three-quarters of an inch long. Now one-sixteenth of an inch from the crown of the hat bore a hole one-sixteenth of an inch at the end of each projection. Bend the outer end of each projecting arm a little less than a quarter of an inch downwards, till it is at right angles to the other part. Make a ring of thin tin three-eighths of inch wide, and one inch and five-eighths in diameter; cut the bottom edge away, leaving three projecting points one-sixteenth of an inch wide and a quarter of an inch long, equidistant from each other, put these projections through the little holes round the crown of the hat, and bend them inwards underneath. This will hold the ring tightly in its place. Now put this hat on the top of the lamp, and mark on one of the arms the place where the iron wire in the movable lower top comes, and then bore in that arm a hole one-eighth of an inch in diameter, and put the top on, passing the upright wire through this hole. Your top will now be likeFig. 24. The ring is to hold the chimney, and should have four or five slits in it a quarter of an inch deep, to clip the glass.
Now solder a handle to your lamp. Make a ring of tin a quarter of an inch wide, and one inch and a quarter in diameter, and solder the two ends to the lamp.
magic lanternFig. 25.
Fig. 25.
On the other side you must make the loop to hold the reflector. Take a piece of tin one inch wide and three inches long, and bend the ends at right angles to the middle, each end to be three-quarters of an inch long. Solder these ends to the front of the lamp. On the front of this piece of tin solder another an inch and a quarter long and three-quarters of an inch wide, soldering only the ends. This will be the loop to slip the hook on the back of the reflector in, and will keep it in its place. Your lamp is now quite finished, and will be as represented inFig. 25. In fastening on this slip care must be taken to put it in such a position that whenthe reflector is in its place the centre of the reflector will be one inch higher than the top of the lamp, that is, the cut crown of the hat.
When using the lantern the lamp must be placed under the chimney, and pieces of board put under it to bring the centre of the reflector opposite the centre of the lens.
Now put a wick in. These wicks are circular, and about three inches and a half long. When buying them, take your wick-carrier with you to get the right size. They should fit tightly over this. These wicks can be bought at the lantern-shops, and are one shilling or one-and-sixpence a dozen. Put oil in your lamp, about two-thirds full. Light your lamp and put it in the lantern. Put the chimney on, put the lenses in their proper places, and try the lantern. If it gives a clear, sharp disc on the wall your lantern is all right, and ready to show the slides. If the disc is cloudy or has dark patches, move the lamp about till you get it clear. Move the front lens till the end of the disc is sharp.
magic lanternFig. 26.
Fig. 26.
You can paint your lantern all over with black paint. Brunswick black is the best to do this with. It makes the tin parts look nice. If you prefer it, and I think it is far the best, you can make your lantern of mahogany instead of deal, and polish it, and blacken the tin parts only. Mahogany board can be got for this very little dearer than deal. If you were to solder a brass-wire ring round the outside of the edge of the tube that carries the front lens, it would make it stronger and easier to regulate the focus, besides giving it a more finished look. If the nozzle and focusing-tube were made altogether of this brass plate it would add to the finish.
A magic lantern without slides is not of much use. These slides cost a good deal to buy, the price, ranging from two shillings to a guinea, being regulated by the time and skill expended in their production. In this section I will tell you how to make your own slides at a small outlay for materials. The time and skill you must supply yourselves.
The materials required are—a glass-cutter; some strips of patent plate-glass four inches wide—the glass of the thickness called eleven-ounce glass; thin black paper, crystal varnish, turpentine, tubes of water-colours, three or four sizes of sable-hair pencils; a good-sized camel-hair brush, with the hair cut straight off half-way down, for varnishing; some glue, two or three small dabbers made of fine linen or kid stuffed with wool, a palette, an easel, and a penknife.
The colours required are opaque black, warm brown, blue, dark green, yellow, and crimson. The palette can be made of a piece of glass six inches square, with a piece of white paper pasted on the back.
magic lanternFig. 1
Fig. 1
The easel you can make for yourselves.Fig. 1will show how mine is made. A board twelve inches square and one inch thick forms the stand. To this, at about one inch from the front edge, is fastened by two hinges another smaller board, eight inches wide and eleven inches long from top to bottom, having a square hole six inches wide and nine inches long cut out of it, making it into a frame. This hole is filled with a plate of glass by glueing strips of wood all round inside the frame at the back for the glass to rest upon. The front surface of the glass must be flush with the front surface of the frame.
Up the front of both sides of the frame holes are bored about half an inch apart for the pegs in the shelf to fit into. This shelf is a piece of wood eight inches long and half an inch square. In the back of the shelf are fixed two iron pegs, which fit into the holes in the frame to keep the shelf in position. At each side of the frame is a wooden support screwed on to the outside by one end, so that it can be moved freely backwards or forwards, hinge fashion: the free end of each support fits into holes bored in the stand. By moving the supports backwards or forwards, and putting them in the holes in the stand, the easel can be lowered or raised at pleasure.
The upper surface of the stand is covered with white paper. You will require a hand-rest to keep the hand from touching the painting. This is made out of a piece of thin wood (cigar-box wood does nicely) eight inches long and one inch wide.To one side of this, at each end, glue a piece of the same wood one inch square, and in these pieces fix the iron pegs to fit into the holes in the frame of the easel.
When using the easel place it with its back to a window, or if you are painting by gas or lamp light place it so that there is a strong light on the white paper under the glass.
The glass to be painted is to be put on the glass of the easel resting on the shelf. When you have finished painting for the day you need not remove the picture from the easel if it is not finished, as by fixing the hand-rest over it and shutting down the easel you can cover the whole with a sheet of paper, and so protect it from dust. Now you have everything you want, and we will set to work at the painting.
First take your strips of glass, and with your glass-cutter cut them into pieces four inches square. Take one of these squares and well clean it on both sides. Put a little of each colour on your palette. Now place your glass over the design you wish to transfer to it, and very carefully go over the outline with your finest sable-hair pencil dipped into the opaque black moistened with a little water.
While this is drying mix in a small bottle some crystal varnish and turpentine in the proportion of one part varnish and two parts turpentine. When the outline is dry take it in your left hand, with the thumb on one edge and the fingers on the other. Dip the varnish brush into the varnish mixture, drain it partly on the mouth of the bottle, and carefully, with a light and free hand, go all over the glass, drawing the brush from top to bottom, beginning at the left-hand edge and working to the right.
Do not go over the varnish twice, or you may disturb the outline. Set the glass on one side to dry, but do not put it where it will get hot, or this may crack and streak the varnish.
While this is drying, take another glass, clean it, and trace outline of number two picture, varnish, and proceed with number three, and so on till you have six glasses outlined and varnished. It is better to have more than one picture to work upon at the same time; you do not then have to wait for the varnish to dry, as you can be colouring one while the other is drying.
When the varnish is dry, which will be in about a quarter of an hour, put one of the glasses, with the varnished side up, on to the easel, place the easel in a good light, and proceed to put in the colours. Put in the sky and background of the pictures first. The sky and all large surfaces must be put in as evenly as you can with the brush, and then you must go all over them with a fine dabber till you have got them perfectly even. In dabbing a surface such as a sky, do not mind dabbing the colour over other parts of the picture, as all the colour not wanted in it can be taken out with the moistened point of a brush before varnishing. When I paint my slides I sometimes purposely colour all over anything that projects into the sky, as I find I can get a more even surface by doing so.
When you have been all over the picture with the first coat of colour, varnish as before, and proceed with the second and third coats. You must be very careful in varnishing the colours, and not go over them twice. The colours are to be got at all artists’ colour shops. Ask for tubes of water-colours for glass-painting. Some of the larger firms also publish little books on glass-painting, in which you will find many useful hints.
When the colouring of the picture is finished, varnish it all over for the last time, and set on one side to dry. Now cut some squares out of your black paper the exact size of your glasses, and cut from the centre of each a circular hole three and a half inches in diameter; place one of these pieces on each of the varnished pictures (on the varnished side); take, and clean, six other glasses, and place one on each of the paper squares on the pictures; next fasten the two glasses together by glueing a narrow strip of paper all round the edges of each pair, and lapping on to each glass not more than one-eighth of an inch.
When they are quite dry your slides are ready for the lantern, and the pictures being inside between the two glasses, will be protected from injury from dust or scratches. In putting the slides into the lantern the painted glass should be nearest the light, if to be shown through a transparent screen; and the other glass nearest the light if to be shown on to a wall or opaque screen.
magic lanternFig. 2
Fig. 2
These slides will be too small to use in the lantern by themselves, so you will have to make a wooden slider for them. This is made as inFig. 2.
magic lanternFig. 3
Fig. 3
Take two pieces of board one-eighth of an inch thick, four and a half inches wide, and eight inches long, with a square hole cut in each three and three-quarter inches square. These boards make the back and front of the slider, and are joined together at the top and bottom by two narrow strips of wood eight inches long, a quarter of an inch wide, and one-eighth of an inch thick. This slider is pushed into the slide-stage of the lantern, and the glass slides pushed into it as inFig. 3.
The slider is rather smaller than the stage in the lantern, which allows of it being adjusted so that the centre of the picture is in a line with the centre of the lenses.
For making movable slides, such as slipping-slides, lever-slides, rack-slides, and chromatropes, you will require wooden frames.
To make these frames, get a carpenter to cut you some slips of pine or deal three or four feet long and half an inch square, with a groove running all along one side of each slip say one-eighth of an inch deep and one-sixteenth of an inch wide. Make your frames out of these slips of wood, seven inches long and four inches wide, outside measuring. Fit a glass in the groove like a slate is fitted in its frame.