Some Simple Aids to Drawing
How to Draw a Circle.
—Should you ever want to draw a circle and have no compasses at hand or should you want to draw a larger circle than you can with your compasses tie a bit of strong thread to a pin, make a loop in the string at whatever length you want the radius—that is half of the diameter of the circle—to be.
This done, drive the pin in at the point where you want the center of the circle, put the point of a lead pencil in the loop and move it around the pin, as shown at [A in Fig. 50], keeping the thread taut and a perfect circle, nearly, will result.
Fig. 50a. how to draw a circle with a thread
How to Draw a Spiral.
—Make a loop in one end of a thread as before and tie the other end tightly to a large pin; wind the thread around the pin until all of it is on except the loop; push the pin through the paper on which you want to draw the spiral and into the drawing board as shown at [B].
Next put the point of the pencil in the loop and move it around the pin just as you did in making the circle and you will find that you have drawn a very pretty geometrical spiral which is known as the spiral of Archimedes. It is so called because Archimedes was the first to explain that it was caused by a point moving with uniform angular speed and receding from the center at a constant rate.
Fig. 50b. how to draw a spiral with a thread
How to Draw an Ellipse.
—An ellipse can be drawn in the same way as a circle, that is, by means of a string; but instead of one pin you will need two and each pin is driven in at the foci of the ellipse you are to draw as shown at [C]. Simply make a loop of the string, slip it over the pins, put the pencil point in the loop and move it around the pins when an ellipse will be formed.
How to Make and Use a Pantagraph.
—A pantagraph is a simple mechanical linkage for enlarging, copying or reducing the size of a picture. It is shown in [Fig. 51].
To make one of these instruments get four strips of wood about ¹⁄₈ inch thick, ¹⁄₂ an inch wide, and 18 or 20 inches long. Now drill ¹⁄₁₆ inch holes ¹⁄₄ inch apart in each stick the whole length of it. In the ends of three of the sticks make a hole the size of a lead pencil.
Fig. 50c. how to draw an ellipse with a thread
Fig. 51. how a pantagraph is made and used
Make two tin tubes each ¹⁄₂ an inch long and fit them into the holes in the ends of the sticks and push a bit of pencil through each tube; screw a block of wood ¹⁄₂ an inch thick to your drawing board and screw one end of another stick to the block and the sticks together with screw eyes.
Now tack a sheet of paper under the pencil in the free end of the stick and a picture under the pencil in the jointed ends of the sticks, then trace the picture with the latter, and the other pencil will make an enlargement of the picture. By changing the position of the sticks a picture can be copied or reduced in the same way. A pantagraph can be bought for as little as 25 cents or for as much as $125.00.[41]
[41] A pantagraph can be bought of any dealer in art supplies or drawing materials.
Fig. 52. how a reflecting drawing board is made and used
How to Make a Reflecting Drawing Board.
—This is a very simple and easily made optical apparatus for copying pictures and making drawings of flat objects. Get a smooth board, or your drawing board will do; make a wood frame and fit an 8 × 10 sheet of clear glass in it and screw the frame to the middle of the board as shown in [Fig. 52].
Now all you have to do is to lay a picture or a flat object, such as a leaf or a butterfly, on one side of the glass and a sheet of paper on the other side and look into the glass at a sharp slant, or acute angle would be the better term, and you will see the picture projected plainly on the paper so that you can easily draw it in with a pencil.
How to Make Tracings.
—A very easy and effective way to copy any picture already drawn, or even a photograph, in line, is to use tracing paper.
This kind of paper, which you can buy of any dealer in drawing materials, is quite transparent and very tough. To make a tracing lay the drawing you want to copy on your drawing board, then lay the tracing paper on top of it, rough side up, and push a thumb tack into each corner to hold them together.
Now trace the outline of the picture with a pencil and then draw in the lines with India ink. If the paper does not take the ink readily rub the surface of it with a little powdered chalk on a soft rag. You can make as many duplicate copies as you want by using a printing frame and blue paper according to the [directions] given in the [next chapter].
To Make Lasting Impressions.
—Here is an easy way to make lasting impressions of your own and your friends’ finger prints and hands.
Take a sheet of heavy glazed white paper, say 5 × 7 inches, and hold it over a kerosene lamp with the chimney removed and the top of the burner thrown back so that the flame will smoke like a locomotive. Keep moving the paper about to make the soot, which is simply particles of nearly pure carbon, cover the surface of the paper as evenly as possible.
Fig. 53. a lasting carbon (soot) impression of your hand
Lay the smoked paper on a table and then press the palm of your hand flat down on it; you must be careful not to press your fingers down too hard or the sharpness of the fine lines will be destroyed. To get a clear impression of the lines in the hollow of your hand press down on the back of it with the fingers of your other hand.
After you have made the print, as the impression is called, pour on some flint varnish, which is the kind that photographers use to cover the films of glass negatives. You can buy it at any photo supply house.
Pour a teaspoonful on one corner of the paper and let it flow down and across until the whole surface is evenly covered. As this is a genuine carbon process the prints cannot fade and they will last as long as the paper lasts. A print of this kind made by the author 18 years ago is shown in [Fig. 53].
The Ancient and Honored Art of Cutting Silhouettes.
—Since you are of the younger generation let me tell you just what a silhouette is, and why.
It is a profile, or side view, of the head of a person cut out of black paper and mounted on a white card, or else cut out of white paper with a piece of black silk back of it so that it looks like a shadow in miniature of the sitter.
It was so called after M. de Silhouette, a French Minister of Finance in 1759; his rigid economy in the conduct of his office caused his name to be tacked on to everything cheap and as photography had not yet been discovered and painted portraits were costly, the paper outlines filled in with black were the cheapest substitute known and hence the name.
But as the years rolled by silhouettes became a dignified and honored art and so when our great grandfather and grandmother wanted to have their pictures made—not taken—they went to a shears and paste artist who cut out their silhouettes.
Fig. 54. silhouettes of your great-grand-pa and great-grand-ma (when they were young)
While the art of cutting silhouettes is all but a lost one because photography is so easy and shows all the details, still you can make them with some black glazed paper and a pair of sharp shears with a little practice.
Take a sheet of black glazed paper[42] about 2 inches wide and 3 inches long and seat your sitter with the side of his or her face turned toward you. Now with a pair of sharp shears begin to cut the paper, starting at the chin and going on up the face to the hair, then around to the back of the head and finally cutting out the collar and bust.
[42] Glazed paper can be bought at stationery stores or you can get it from Dennison Mfg. Co., 5th Ave. and 26th St., N. Y. C.
All the time you are cutting you must keep your artistic eye on the profile of your sitter and your mechanical eye on your shears and paper and you will be truly surprised to find how little knack it takes to get a reasonably faithful likeness. A pair of silhouettes are shown in [Fig. 54].
Transfer Pictures, or Decalcomania.
—Of course you know what transfer pictures are. There are very few boys indeed who have not bought and used little 5 cent packages of jim-crow transfer pictures and you will remember that usually only about half of the picture transferred came off. But this was because they were made for fun and not for real work.
Now transfer pictures, or decalcomania (pronounced de-cal´-co-ma´-ni-a) or decalcomanie as the French call it, from the Latin de which means down, plus calquer, which is Latin for trace, plus mania which is Greek for madness, are used by hundreds of thousands by painters and decorators in every line of work. These pictures are made with skill and care and when used properly will not break or come off.
These transfer pictures can be bought in 10,000 different subjects and cost from 1¹⁄₂ cents to a couple of dollars each. The pictures include every subject imaginable from simple little flowers to birds with wonderful plumage and from cupids in groups to world’s fair buildings; then there are letters and monograms and beautiful crests and coats-of-arms in gold and brilliant colors.
When you get ready to do decalcomanie write to Palm, Fechteler and Company, 67 Fifth Avenue, New York, or to their western branch at 54 West Lake Street, Chicago, Ills., for a price-list and this will give you a description, the height and length of each picture, the number of pictures on a sheet and the price per sheet.
How to Transfer the Pictures.
—The regular pictures can be transferred to wood, metal, painted surfaces, etc., but instead of soaking them in water alone as you used to with the toy pictures you give the face of them a very thin coat of a good, quick drying, rubbing varnish which you can get at a paint store, or better, use a transfer varnish which you can buy of the above company for 35 cents for a ¹⁄₂ pint can.
After you have applied the varnish to the face of the picture let it dry until it is very tacky; now put the face of the transfer down on the surface, wet it with water on a sponge and roll it down hard with a felt roller.
In a couple of minutes wet the paper again thoroughly with water and peel it off; roll it down at once with a wet felt roller and tap it off with a piece of chamois skin. After the design or picture has dried for 20 minutes or so, the varnish around it can be removed by dampening it with dilute turpentine, ammonia or, better, with a detergent made of equal parts of turpentine and crude oil and immediately rubbing it away lightly and quickly with a dry, soft rag.
After the picture has been transferred as above, it should be given one or more protecting coats of varnish the next day.
CHAPTER VI
SOME KINKS IN PHOTOGRAPHY
Since the slogan you press the button and we’ll do the rest has come to be so well known everybody makes photographs. But there are a number of kinks in and side issues of photography that are amusing, instructive or useful and which if you do not already know about will prove of service to you.
How to Make Blue Prints.
—This is the very simplest and one of the most useful kinds of photography. You need but very little material to make the pictures with and the little you need will cost less than a dollar.
Fig. 55. a photo printing frame
The Materials Required.
—Buy, or you can make, (1) a 5 × 7 printing frame as shown in [Fig. 55] and get a sheet of clear glass to fit it, and (2) a couple of dozen sheets of 5 × 7 blue-paper[43] which you can buy at any photographic supply house.
[43] You can make blue print paper by dissolving ammonium ferric citrate in warm water and coating the surface of the paper with it by floating it on top of the solution.
Now take one of the drawings you have made on tracing paper or on tracing cloth with India ink as I [described] in the last chapter and lay it with its inked surface on the glass; lay on this a sheet of blue-paper with its sensitized side on the tracing paper or cloth; put the back of the printing frame on top of the blue-paper, press the springs into place and set the frame in the sunlight.
Every few minutes open a half of the hinged back of the printing frame and take a look at the blue paper to see if the printing is far enough along. When the lines of the drawing show plainly on it take the print out of the frame and wash it, as it is called, by letting water run on it or by putting it through several changes of water.
When it is well washed hang it up on a line by a corner to dry and you will have a good, clear print with white lines on a blue ground. In this way by using a negative that you have made with a camera, especially if it is a marine view, you can get some very pretty and artistic pictures.
Another Kind of Contact Printing.
—If you like nature you can use the above process of contact printing to fine advantage. Instead of blue paper it is better to use what is known as solio paper[44] or silver paper.[45]
[44] Solio paper is coated first with gelatin and then with silver.
[45] Silver paper is coated first with albumen and then with silver.
To make a contact silver print first put a finely veined leaf, the filmy wing of a butterfly, a piece of delicate lace or any other thin, translucent object on the glass in the printing frame, lay a sheet of solio, or silver paper over it, then put the back in the frame and fix the springs.
Set the frame so that the sunlight will fall full on the glass side of it. From time to time open half of the hinged back and see how the print is coming on; make the print a couple of shades darker than you want it when finished, but be careful not to overexpose it for silver paper prints much quicker than blue paper.
To Tone and Fix the Picture.
—To tone a silver print means to change its color and give it more brilliancy and this is done by putting it in a chemical solution made of chloride of gold, or toning bath as it is called.
To fix a print means to treat it so that the light will no longer act upon it and this is done with a solution of hyposulphite of soda or just hypo as it is called for short.
The easiest way to tone and fix your silver prints is to buy a bottle of solio toning solution[46] which is a combined toning and fixing bath. Take the print from the frame and do not wash it but put it into a tray in which you have mixed 2 ounces of solio toning solution and 4 ounces of cold water.
[46] It can be bought at any store where photographic materials are sold or you can make it yourself from the [formula] given on this page.
When the print takes on the proper color put it into another tray containing a solution made of 1 ounce of salt and 32 ounces of water; let it stay in this bath for 5 minutes to stop the toning. Now put the print into another tray and wash it in 16 changes of water or in running water for an hour. If you make a half or a dozen prints at once you can tone and fix them at the same time.
Recipe for a Combined Toning and Fixing Solution.
—To make a combined toning and fixing bath mix up two solutions, called stock solutions, as follows:
Stock Solution A.
—Dissolve in 20 ounces of cold water 2 ounces of hypo, 1¹⁄₂ ounces of alum in crystals and ¹⁄₂ an ounce of granulated sugar. Then dissolve ¹⁄₂ an ounce of borax in 2 ounces of hot water and mix it with the hypo solution; let it stand over night and then pour off the clear liquid.
Stock Solution B.
—Dissolve ³⁄₄ of a grain of pure chloride of gold and 32 grains of acetate of lead in 4 ounces of water.
Now when you want to tone a picture or half a dozen 4 × 5 prints, take 4 ounces of the stock solution A and ¹⁄₂ an ounce of the stock solution B and pour them into a tray and tone them as I have previously described.
The Simplest Kind of a Camera.
—When you can buy a real camera for two or three dollars it seems of little use to make one, so just consider the camera I shall describe as a scientific curiosity rather than an apparatus of utility.
Fig. 56. an easily made pin-hole camera
A. Cross section showing the notched strips.
B. The way the shutter works.
To make a pin-hole camera, so called because a pin hole takes the place of a lens, form a box of pasteboard or of thin wood 4 inches square and 8 inches long; cut a hole ³⁄₈ of an inch in diameter in one end for the pin hole. Fit a strip of wood ¹⁄₂ an inch thick and 4 inches long, having notches cut into it to a depth of ¹⁄₈ inch, to the sides of the box as shown at [A in Fig. 56]. These notched strips are to hold a sensitized dry plate.[47] Next make a shutter, that is, a little device to open and close the pin-hole; it is simply a bit of sheet brass 2¹⁄₂ inches long, ¹⁄₄ inch wide at one end and ¹⁄₂ an inch wide at the other end as shown at [B]. Drill a hole ¹⁄₈ inch in diameter in the center of the strip of brass and pivot this to the front of the box so that it is on a horizontal line with the center of the hole.
[47] A dry plate is a sheet of glass coated on one side with gelatin and bromide of silver which makes it sensitive to light.
Now to make the pin-hole, and certainly no pin-hole was ever more important than this one. Glue a thick piece of nice smooth tinfoil over the hole on the inside of the box and with a fairly good-sized pin, or better a needle, prick a smooth hole in the center of it.
You are ready now to take a picture and to do so slip a sheet of ground glass[48] into the grooves in the camera up close and then farther back until you can see the picture plain. This done take the camera into your dark-room,[49] and load a dry plate into it, put the cover on the box and fasten a black cloth over it with a rubber-band as shown at [C in Fig. 56].
[48] You will find [directions] for making it in [Chapter IX].
[49] A dark room must be used because a ray of any kind of light except red will spoil a dry plate the instant it strikes it. A red-lamp can be bought for a quarter or you can make one and either use a sheet of red glass or red dark-room paper.
Go out and point your camera at the object you want to photograph, be it a landscape, a seascape or a scapegoat, press down on the lever for a second, let go of it when it will drop back and cover the pin-hole again and the exposure is made.
How to Develop a Dry Plate.
—Next take your camera into your dark-room and develop the plate, that is, immerse it in a chemical solution called a developer to bring the picture out on it. To do this you must get a tray and put the exposed dry-plate in it, film side up, and pour the developer over it.
Fig. 56c. the pin-hole camera complete with cloth and rubber band
Rock the tray after you have poured the developer over the plate to keep the solution flowing forth and back evenly over it all the time. When you see the image very plainly take the plate out of the developer, wash it in clean water and then lay it with the film side up in a tray containing the fixing bath.
Let the negative—when the plate is exposed and developed it is called a negative—remain in the fixing bath until all the white parts, that is, the free silver which was not affected by the light, have disappeared and then let a gentle stream of water run on it for an hour or wash it in 16 changes of clean water. Stand it in a negative rack over night to dry and then you can make prints from it.
How to Make the Developer.
—You can make a good, tried and true developer in two solutions as follows:
Pyro Solution, A.—Take 1 ounce of pyrogallic acid, called pyro for short, dissolve it in 28 ounces of water and then add 20 minims of sulphuric acid.
Soda Solution, B.—Dissolve 2 ounces of desiccated[50] carbonate of soda and 3 ounces of sulphite of soda in 28 ounces of water.
[50] Desiccate means thoroughly dry.
When you want to develop a plate mix ¹⁄₂ an ounce of the pyro solution and ¹⁄₂ an ounce of the soda solution with 4 ounces of water and to do this you need a graduated glass.
How to Make a Fixing Bath.
—To make a good fixing bath for dry plates dissolve 1 ounce of hypo, 60 grains of sulphite of soda in crystals and ¹⁄₄ ounce of borax in 20 ounces of water. A developer can only be used for one or two plates but you can fix 50 plates in the same fixing bath.
A Good and Cheap Camera.
—To take real pictures you want a real camera. Now there are many kinds of hand cameras but there is only one size that I am going to try to interest you in and that is one which will make pictures 3¹⁄₂ × 4¹⁄₂ inches.
With a camera of this size you can take nicely proportioned little pictures to give to your friends, to keep in your album, to make enlargements of and to make lantern slides of by direct contact printing and this will save you a lot of trouble.
Fig. 57. two cheap and good cameras
A. A Brownie box kodak.
B. A folding kodak.
The cheapest 3¹⁄₄ × 4¹⁄₄ camera you can buy is a No. 3 Brownie box kodak,[51] see [A Fig. 57], which costs about $3.00. A folding No. 3 Brownie camera, shown at [B], will serve your needs much better and this one will cost you in the neighborhood of $5.50, or you can buy a Graflex camera[52] for $75.00 if father is rich and mother doesn’t care.
[51] These cameras can be bought most anywhere or you can send to the Eastman Kodak Company, Rochester, N. Y.
[52] With this kind of a camera you can see the object you are photographing up to the very instant you snap the shutter.
Every good camera has what is called a rectilinear lens, that is, a compound lens formed of two achromatic lenses, which means that each acromatic lens is made up again of two lenses one of which is of crown glass and the other is of flint glass, and these two latter lenses are cemented together with Canada balsam.[53]
[53] This is a clear gum that is obtained from a tree called the Canada balsam.
Now whereas a common convex lens will produce all the colors of the rainbow around its edges when a ray of light passes through it, an acromatic lens lets through only the white light and while a single convex lens makes the straight lines of a building curved in the picture, an acromatic lens keeps all the lines straight, or rectilinear, and hence its name.
These little cameras are filled with mechanical snap shutters and they use roll films, that is the sensitive silver and gelatine emulsion is spread on a thin celluloid film instead of on glass plates. These roll films come on spools in lengths of ¹⁄₂ and 1 dozen each and they can be loaded into the camera in daylight. The same kind of developing and fixing solutions are used for films that are used for dry-plates.
How to Make an Enlarging Apparatus.
—To make an enlarged picture of a small negative take out the back of your camera and get two perfectly clear sheets of glass to fit the opening.
Make a box of ¹⁄₄ inch thick wood, 6 inches wide, 6 inches long and 7 inches high and have the top of it separate so that it can be lifted off and put on the box. In the middle of the top near one edge cut a hole 1¹⁄₄ inches in diameter and put an electric light socket—to which a cord and plug is fixed—in it as far as it will go and then screw in a nitrogen 100 watt electric lamp[54] which gives about 75 candle power, as shown at [A in Fig. 58].
[54] The Delco Light Co., 52 Park Place, New York, sells these lamps and all other electrical supplies.
Fig. 58a. a home-made enlarging apparatus
The lamp set in the top of the illuminating box.
Cut a hole out of the front board 3¹⁄₂ x 4¹⁄₂ inches and fasten a sheet of ground glass[55] or, better, of opal glass[56] over the opening. Get a sheet of bright tin 6 inches wide and 10 inches long, bend it into a semi-circle and set it in the box so that it will reflect the light from the lamp in front of it through the ground glass screen as shown at [B].
[55] Ground glass can be bought at a glazier’s or you can make it as [explained] in [Chapter IX].
[56] Opal glass.
Next make a stand for holding the bromide paper[57] which is to be used for the enlargement. About the easiest way to do this is to take a 1 inch thick board 6 inches wide and saw off a piece 12 inches long. Fasten your drawing board to it with a couple of angle blocks as shown at [D], and you are ready to make an enlargement.
[57] Bromide paper is a paper sensitized with a compound of silver and bromine.
How to Make an Enlargement.
—When you have the apparatus ready set the camera and the illuminator, as the box with the light in it is called, on another table. Put the negative between two plain sheets of glass and then fasten them to the camera with a couple of large rubber bands; set the illuminator with the ground-glass screen close up against the negative in the back of the camera, as shown at [C].
Now set the drawing board stand about 4 feet away from the lens of the camera to make an 8 × 10 enlargement. Open the shutter, turn on the light and focus the camera, that is, move the stand to and from the camera until the enlarged picture is sharp. When you get it so, close the shutter and cover up the cracks where the light leaks through with a dark cloth.
Make the room perfectly dark except for your dark-room light and then put a sheet of bromide paper on the drawing board with thumb tacks. Open the shutter of the lens and expose the paper to the light passing through the negative and then close it again. The bromide paper is developed and fixed just like a dry plate when your enlargement is done.
Fig. 58b. a home-made enlarging apparatus
B. The illuminator showing the tin reflector in it.
C. The camera.
D. The stand for holding the bromide paper.
In handling bromide paper you must be almost as careful as you are with dry plates or films. Before making a picture it is a good scheme to test the length of time to expose the paper. To do this take a sheet of bromide paper and cut it into strips 1 inch wide and 10 inches long; fasten a strip at a time diagonally across the board and expose the first one for say 5 minutes and then develop it, when you can usually tell about how long the exposure should be.
A Developer for Bromide Paper.
—A good stock solution developer for bromide paper, velox paper, films and dry plates can be made by adding these chemicals to 25 ounces of hot water in the order named and stirring in each one until it is dissolved; elon ¹⁄₈ ounce; desiccated sulphite of soda 1⁷⁄₈ ounces; hydrochinon ¹⁄₂ ounce; desiccated carbonate of soda 5¹⁄₄ ounces; potassium bromide 30 grains and wood alcohol 3 ounces.
Fig. 58c. a home-made enlarging apparatus
E. Cross section top view of the enlarging apparatus.
This developer will keep for a long time if the bottle containing it is kept full, otherwise the air will act on it. To develop six 8 × 10 bromide prints use 1 ounce of the stock solution and 6 ounces of water.
To fix bromide prints keep them moving in a bath made by dissolving 8 ounces of hypo in 2 quarts of water and then adding ¹⁄₄ ounce of metabisulphite of potassium and ¹⁄₄ ounce of powdered alum. Let the prints remain in this bath for about 10 minutes and then wash them thoroughly.
How to Make a Reflectoscope.
—A reflectoscope is a kind of magic lantern but instead of using transparent glass slides you can use any picture or opaque object such as the works of a watch, your hand, etc, and throw an image of it on the screen.
Fig. 59 a cheaply made reflectoscope
A. The projector.
B. The illuminator.
If you have a folding camera[58] you can convert it into a dandy reflectoscope, so get busy with your tools. Make a box—it is really two boxes fastened together—of the peculiar shape shown in [Fig. 59], and it can be of wood or of metal as you wish.
[58] A box camera can not be used because its focus is fixed.
First make the larger box, which we will call the projector, and this should be 4¹⁄₂ inches long, 5 inches wide and 5 inches high[59]—and leave the front, back and one side off. To the top and bottom fasten on two wood cleats ¹⁄₂ an inch square and 5 inches long to fix the projector to the camera with. This box is shown at [A in Fig. 59].
[59] It must fit the back of your camera.
Fig. 59c. a cross section top view of the reflectoscope
This done, make another box for the illuminator 3 inches wide, 3 inches long on one side, and 4³⁄₄ inches long on the other side, and 5 inches high. Bend a piece of bright tin for the reflector and set this in the back as shown at [B].
Cut a 1¹⁄₄ inch hole through the top for an electric lamp as [described] in the directions for making an enlarging lantern; the top should be tight fitting but so made that it can be taken off and put on at your pleasure.
Now glue, screw, solder or otherwise fix the two boxes together and the reflecting part of the apparatus is done. To complete it fasten the back of your camera to the cleats on the top and bottom of the box with strong rubber bands as shown at [C], which is a top view of the reflectoscope.
Fig. 59d. the reflectoscope ready for use
To Use the Reflectoscope.
—Tack a white sheet to the wall and set the reflectoscope at a distance of about 10 feet from it with the lens pointing toward it, of course.
Next turn on the light in the box and turn off all the lights in the room and make it as dark as you can. Hold a picture of any kind against the opening in the back of the projector box and then focus the camera until the picture on the screen is as sharp as you can get it.
The way the reflectoscope works is like this: the picture is projected upon the screen in virtue of the fact that the direct light from the lamp, as well as that portion of it which is reflected back by the tin, is thrown against the surface of the picture or object held in the opening; from this the light is reflected through the lens which enlarges it and projects it on the screen.
How to Make a Magic Lantern.
—To make a magic lantern out of a camera is just as easy as it is to make a reflectoscope but you will have to buy a condensing lens[60] and this will cost 50 cents to $1.00, according to size.
[60] The L. E. Knott Apparatus Co., Boston, Mass., sells a 2 inch condensing lens for 50 cents; a 3 inch one for 75 cents, and a 4¹⁄₂ inch one for $1.10.
For this lantern you can use either a box or a bellows camera, though the latter is better because the picture can be focused. Whichever you use make a base of a 1 inch thick board, 5¹⁄₂ inches wide and 14 inches long and nail or screw two strips of wood ¹⁄₂ an inch wide, ³⁄₄ inch high and 8 inches long along the edges on one side as shown at [A in Fig. 60].
If your camera is of the box kind set it in between the strips on the base on the front end, but if it is of the bellows type then you will have to make a shelf for it as shown at [B] to hold the camera in place as shown at [C].
Next make an illuminator as [described] above in the text How to Make an Enlarging Apparatus, but instead of covering the front with ground glass make a board to fit it and cut a hole in it the exact size of the condensing lens. This lens is a plano or a double convex lens as shown at [D] and while it should be 4¹⁄₂ inches in diameter to get all of the picture on the screen you can use a lens as small as 2 inches though all of the picture will not show.
 | ||
| THE BASE OF THE LANTERN | THE FRAME TO HOLD A POCKET FOLDING CAMERA | HOW THE CAMERA IS FIXED TO THE FRAME |
 | ||||
| PLANO CONVEX | DOUBLE CONVEX | ONE OF THE LANTERN SLIDE HOLDERS | FRONT BOARD ILLUMINATOR | |
| CONDENSING LENSES | ||||
Fig. 60. the parts of a home-made magic lantern
Cut out six clips of sheet brass ³⁄₁₆ inch wide and ¹⁄₂ an inch long and punch a hole in the end of each piece. Screw three of these clips to each side of the board at equi-distant points around the hole so that the end of each one projects over the edge of the hole ¹⁄₈ inch. Now put the lens in the hole and adjust the ends of the clips so that they will hold the lens in place as shown at [E].
The next and last thing to do is to cut two strips of tin or brass 1 inch wide and 3 inches long and bend each one over the long way as shown at [F]; punch three holes near the lower edge of each one and screw one of them above and one below the condensing lens on the board 3¹⁄₄ inches apart as shown at [E]. These bent strips form the holder for the lantern slides. The magic lantern complete is shown at [G].
Fig. 60g. the magic lantern ready for use
How to Work the Lantern.
—Tack a bed-sheet up on the wall; turn on the light in the illuminator and turn off all the lights in the room; slip a lantern slide upside down in the holder and then push the rear end of the camera—having first taken out the back—close up to the lantern slide holder.
If you are using a box camera move the whole lantern back until the picture is as large as you want it and it is still bright enough. If it is a pocket folding camera you can focus it and get a picture with much better definition.
How to Make Lantern Slides.
—A lantern slide is a sheet of glass with a transparent picture on it. A standard lantern slide is 3¹⁄₄ × 4¹⁄₄ inches and one of this size can be used in any full sized magic lantern or stereopticon.[61]
[61] A stereopticon is really two magic lanterns, but the word is now often used to mean a high-grade magic lantern.
To make lantern slides by direct contact printing is not a hard thing to do at all, and all the equipment you need to make them besides the chemicals is a printing frame. Put a sheet of clean glass in it and lay your negative on it with the film side up.
Now lay the lantern slide plate[62] with the film side down on the negative just as though you were going to make a print, but you must make it in your dark room, using a white light to expose it of course, for it is just as sensitive as a dry plate or a film. When you expose it hold the printing frame about 12 inches away from the light.
[62] Lantern slide plates can be bought at any photographic supply house.
A lantern slide plate is developed, fixed and washed exactly like a dry plate but to get the best results you should use the kind of developer called for in the directions that come with the plates.
When you have the lantern slide made, place a sheet of clear glass of the same size—called the cover-glass—on the film side of it and bind the edges with passepartout binding, that is a strip of paper gummed on one side. It is then ready for use.
How to Make Radium Photographs.
—You can make radium photographs, or skiagraphs as they are called, with any one of a number of radioactive substances and at a very small outlay.
The four most important radioactive substances, if we except radium itself, are black uranium oxide, pitchblende, thorium nitrate and uranium nitrate. You can buy any one of these substances in a glass stoppered bottle for $1.00 or the set of four for $3.50.[63]
[63] The L. E. Knott Apparatus Co., Boston, carries these radioactive substances in stock.
While the radioactivity of these substances is low it is sufficient to make a shadow-picture—and this is all that an X-ray picture is—of a coin or other small object if it is laid on top of a dry plate sealed in a black paper envelope, which is opaque to the light.
Fig. 61. a photograph of a coin made with radium
That is, the coin is laid on the envelope containing the dry plate, and the bottle with the radioactive substance in it is laid on top of the coin. Let them remain undisturbed in this way for a couple of days and you will find on developing the plate a very good radiograph, or shadow picture of the coin as shown in [Fig. 61].