Chapter XVIII: Part II: A Festooned Kite (4)

Corn Popper Made from Coffee Can and Broom Handle

With an old coffee can, or similar tin receptacle, and a piece of a broom handle, 2¹⁄₂ or 3 ft. long, it is easy to make a corn popper that is preferable in many ways to a wire one. Take a strip of wood a little shorter than the height of the can to be used, and after boring two holes in it to prevent its splitting, nail it to the end of the handle. The latter is then fastened to the side of the can with two wire staples, as shown. Holes are made in the can top to admit air to the corn while it is popping.--James Crouse, Dixon, Ky.

An Easily Constructed Ball-Bearing Anemometer

BY THOMAS A. REYNOLDS

An anemometer is an instrument which measures the velocity of the wind. The anemometers used by the weather bureau consist of four hemispherical cups mounted on the ends of two horizontal rods which cross at right angles and are supported on a freely turning vertical axle. Since the concave sides of the cups offer more resistance to the wind than do the convex sides the device is caused to revolve at a speed which is proportional, approximately, to that of the wind. The axle, to which the rotary motion is transmitted from the cups, is connected to a dial mounted at the foot of the supporting column. This dial records automatically the rotations. The reproduction of such a registering mechanism would be rather complicated. Hence, in the arrangement to be described none will be employed. Therefore, one of these improvised anemometers, when mounted on a high building, will indicate by the changing rapidity of its revolutions only the comparative, not the real, velocity of the wind.

In constructing the instrument, straight, dished vanes will be used instead of hollow cups. The vanes operate almost as effectively and may be combined more readily into a sturdy rotating unit. A bicycle front hub is utilized to constitute a wear- and noise-proof bearing having minimum friction. Each of the four wings is formed from a piece of galvanized iron, measuring 4¹⁄₂ by 10 in., which has one end cut to a curve as shown. To each wing is fastened, with tinners’ rivets, a 4-in. length of ³⁄₄ by ¹⁄₁₆-in. strap iron. Form each of the strips into a trough-shaped vane, measuring 2¹⁄₄ in. from edge to edge--this being the distance between the spoke flanges of a bicycle hub. Some cylindrical object of suitable diameter will serve as a form for bending. Place the ends of the support strips between the spoke flanges and rivet them securely. The rivets pass through the spoke holes. Some trying out may be required to insure a symmetrical arrangement of the parts. Solder the curved end of each wing to the inner surface of the adjacent wing. Place a tin cap--a salve-box lid will do--under the upper locknut on the hub to exclude rain from the bearing.

The supporting upright may be a heavy wooden rod, or a piece of iron pipe. A yoke of 1 by ¹⁄₈-in. strap iron, held to the top of the upright with screws, is provided for the attachment of the hub. The locknut on the hub clamps it to the yoke. Apply a coat of metal paint to the iron parts which are exposed. Mount the device sufficiently high to give the wind free access to it from all directions. The curve at one end of each wing is an irregular one. Hence, its accurate construction involves a knowledge of sheet-metal pattern drawing. However, if it is made of a form similar to that shown it will fit sufficiently well to permit a good soldered joint.

* * * * *

¶Boards exposed to the weather should be laid with the heart side
down, as determined by examining the end grain.

FIG. 3

FIG. 1

Sharpened Poles, Two Feet Long, are Used with This Pile Driver in Building Foundations, Wharves, and Other Structures of Piling. The Details of the Headblock and the Nipper Device are Shown in Figs. 2 and 3]

BY EDWARD A. KRUEGER]

[These directions will enable boys of varying skill with tools
to make a pile driver, as a toy or model. Several simple methods
of making the parts in the home workshop, with materials easily
obtainable, are suggested.--Editor.]

The construction of small docks, wharves, piers, and foundations or bridges, buildings, and other structures, by the driving of piling is interesting out-of-door play, in which boys will find much fun. A pile driver for this work is shown in the page plate, Fig. 1. The hammer is raised by means of a winch, and is dropped automatically when it reaches the cap of the derrick, as indicated in Fig. 3. The drum is then released, and the weighted double-hook nipper drops down, picking up the hammer on the next upstroke. A single-hook nipper, that can be made easily of wire, is also shown in the detail sketch, Fig. 6. The small boy who cannot make the nippers or the winch, may tie the rope directly to the hammer, drawing it up by hand, and dropping it as desired. The hammer need not be fitted to the guides, but merely arranged to drop between them, and the derrick can be made of only a few main pieces. The larger parts of the hammer and nipper weight are best made of lead, babbitt, or white metal, as these may be cut or melted readily. Iron, brass, or copper, solid or in plates, may be used, if means for shaping them are at hand.

The making of the derrick may be undertaken first. Make two pieces for the bed A, ⁷⁄₈ by ⁷⁄₈ by 17 in.; two hammer guides B, ⁷⁄₈ by ⁷⁄₈ by 33¹⁄₈ in.; one bed piece, C, ³⁄₈ by ⁷⁄₈ by 20 in.; two bed pieces, D, ³⁄₈ by ⁷⁄₈ by 5¹⁄₄ in.; two posts, E, ¹⁄₂ by ¹⁄₂ by 34¹⁄₂ in.; two braces, F, ³⁄₈ by ³⁄₄ by 26¹⁄₂ in. Cut these pieces slightly over their finished lengths as given, allowing for trimming and fitting. Make strips, ¹⁄₄ by ¹⁄₂ in., for the bracing on the sides of the derrick and the ladder bracing on the back.

Notch the lower ends of guides B, ¹⁄₈ by ⁷⁄₈. and the lower ends of posts E, on an angle, ¹⁄₈ in. deep, to fit pieces A. Join the parts of the bed, as shown in the page plate, pieces A being set 3¹⁄₂ in. apart, fastening them with bolts or screws. Make braces G, of sheet metal, and bolt them in place. Fit the posts E into place, and fasten them at the bed and the top. Put on several ladder braces temporarily, to steady the frame. Fit the braces F carefully, and bolt them in place. Remove the piece C and the braces F, and nail the horizontal bracing to the sides of the frame. Then fit and nail the diagonal braces. The bolted construction is convenient in “knocking down” the derrick for storing it. Reassemble the parts, and make the cap for the headblock.

The headblock and cap are shown in detail in Figs. 2 and 3. Make two pieces, H, ¹⁄₄ by 1⁵⁄₁₆ by 1³⁄₄ in.; one piece, J, ¹⁄₄ by 1 by 1³⁄₁₆ in.; two braces, K, ¹⁄₄ by 1¹³⁄₃₂ by 1³⁄₄ in. Make the two beveled pieces of the cap ⁷⁄₈ by 1³⁄₄ by 1¹⁄₂ in., and provide a wooden strip or metal plate for the front and rear edges, as shown. Fasten strips of sheet metal to the bevel of the notch, to protect it from wear by the striking of the nipper hooks. Make the sheave 1¹⁄₂ in. in diameter and ³⁄₈ in. thick, with a groove for the rope. Assemble the parts, as shown.

The details of the winch are shown in Figs. 4 and 5, and the method of assembling the parts, in Fig. 1. The drum may also be driven without gears by fixing the crank directly to the shaft. Gears may be obtained from old machines, or purchased from dealers in model supplies. Make the supports L and M, Fig. 4, ³⁄₄ by 4 by 6⁵⁄₈ in., cutting patterns of paper, if desired.

The Supports of the Winch are Made of ³⁄₄-Inch Wood, Bolted to the Bed]

The gear, Fig. 5, is 3¹⁄₂ and the pinion ³⁄₄ in. in diameter. The drum is of wood, 2 in. in diameter and 3⁵⁄₁₆ in. long. Its ends are 3¹⁄₂-in. metal disks, fastened with screws. The shaft is a ³⁄₈-in. bolt, 5³⁄₈ in. long, and bears in holes bored in the supports, as shown in the details of these parts. The crank N, Fig. 5, is made of a ³⁄₁₆-in. rod, bent as shown, and fitted with a washer to fit next to the pinion. The gear is set by means of the pawl O, which is bent from a strip of ¹⁄₁₆-in. sheet metal. The brace P is bent from a ¹⁄₁₆ by ³⁄₄ by 1⁵⁄₈-in. strip of sheet metal, and riveted to the pawl. Assemble the parts, fastening the gear to the drum end, and bolt the supports into place. Put the pinion into mesh with the gear at its proper place, and carefully mark the hole for the crank. Square the end of the crank and the hole in the pinion, and fit them to a driving fit. Fix the rope to the drum, and reeve it through the head block. The derrick is then ready for the hammer and the weighted nipper.

Details of the Drum, Its Driving Mechanism, and Fittings]

The hammer, shown in Fig. 6, may be made easily from a solid block of lead, 1¹⁄₄ by 2⁵⁄₈ by 2⁵⁄₈ in. Cut ³⁄₁₆ by ⁷⁄₈-in. grooves in the vertical edges to fit the guides. Make the circular ³⁄₁₆ by 1⁵⁄₈-in. hammer plate Q of iron or brass, and fasten it with screws. Rivet the wire lifting strap R, as shown.

A Simple Method of Making the Tripping Device, and Details of the Hammer]

The single-hook nipper, shown in Fig. 6, is made as follows: Flatten a piece of ³⁄₁₆-in. wire at the middle, and drill a ³⁄₃₂-in. hole for the bolt. Shape the lower end into a pointed hook, and bend the upper end to form the trip arm. This strikes the notch in the cap of the derrick, releasing the hammer. The rope is wired to the hook as shown. The nipper weight is made of a solid piece of lead, 1¹⁄₄ by 2⁵⁄₈ in., by 1 in. high, grooved at the ends to fit the guides. Cut a slot through it, for the hook, as shown in Fig. 6, and bolt the latter into place. The double-hook nipper is better mechanically, and may be made of two pieces of wire, or cut from sheet metal.

Test the action of the nippers, and bend or file the hooks to operate properly. The pile driver may then be painted, and work on “jobs” begun. If it is used at the water, fix metal guards at the lower ends of the guides, to prevent the hammer from falling into the water.

Split Needle Causes Echo on Talking Machine

An amusing stunt is to split the end of a fiber talking-machine needle carefully about ¹⁄₄ in., so as to make two points, slightly separated. The needle is then placed on the machine, preferably on an old record, so that the points play the record successively, producing an echo. If the work is carefully done, and the points are separated slightly, both reproductions will be fairly clear.--Frank Murphy, Faribault, Minn.

Weighting a Metal Base

Having to weight a shallow metal base to support a 4-ft. brass tube, I found that the easiest way was to fasten four screws on the base with nuts, as shown in the illustration, and pour in lead. The screws were taken out in polishing the base.--James M. Kane, Doylestown, Pa.

* * * * *

¶In toasting bread over a camp fire, it is best to cover the fire
with a tin pan.

Trunk Bookcase for Convenient Shipment

Mechanics, engineers, and other persons are sometimes engaged in work which keeps them at the same locality only a few months. Those who desire to carry with them a small library will find the trunk bookcase, as shown, convenient. It may be shipped as a trunk, and used as a bookcase in one’s hotel or dwelling. Other articles than books may be packed in it. The outside dimensions when closed are 31 by 18 by 18 in., providing for three shelves. It may be made of ³⁄₄-in. pine or whitewood, and stained, or covered with impregnated canvas. The outer corners are reinforced with metal corner plates, and suitable hardware is provided.--Lloyd C. Eddy, Jr., Buffalo, N. Y.

Bottle Carrier Made of Pipe Straps

Two metal pipe straps, fitted around the neck of a bottle and bolted together, form a convenient method of attaching a carrying handle to a large bottle. The handle proper is made by fixing a grip in a bail of wire similar to that on a bucket.

A Developing or Etching-Tray Rocker

An appliance that saves time for the worker in a photographic dark room is a tray rocker, made as follows: Fasten a bracket of strap iron, into which are riveted the pointed ends of two spikes, to the under side of a board, as shown in the detail sketch. Support this further with a double angle fastened at the end of the board. Fix a small can, weighted with lead, on the end of an iron rod, adjusted to a suitable curve, and fasten the rod to the bracket. The weighted end should extend under the edge of the table, as shown, and be balanced so that it will rock the board and tray without tipping the latter toward the bracket. The nails pivot on metal pieces, to protect the table top.--L. L. Llewellyn, Piedmont, Calif.

Combination Laundry Tub and Dishwashing Sink

A saving of space and time was effected in a home kitchen by the use of a sink developed in a large kitchen. Two ordinary laundry tubs were installed with the faucets raised above the tubs, as shown. A sink of sheet zinc was fitted in the upper part of one tub; it has handles, and a strainer set in the bottom. The strainer is closed by a rubber stopper, and the sink becomes a dishpan. The sink is easily lifted out for cleaning, or for washing clothes. Another use for the sink, between meals, is for washing and preparing vegetables and fruits. The second tub has a wire dish-draining rack, in which the china is rinsed and sterilized by hot water from the faucet.--Mrs. Avis Gordon Vestal, Chicago, Ill.

A Leather and Silk Bookmark

A Jolly Good Book
Wherein To Look
Is Better To Me
Than Gold]

An artistic and useful bookmark was made from a silk ribbon passed through a buckle of leather, tooled with an inscription and a conventional design. Ribbon of various sizes may be used, and the leather left plain if desired. The ends of the ribbon are fringed, as shown. Monograms make interesting and individual decorations for the leather portion.--Will Chapel, Manchester, Ia.

Emergency Oarlock of Rope

An oarlock that will give considerable service may be made by fixing a loop of rope to the gunwale of a boat at the proper position. This kink is useful in an emergency, such as when an oarlock is dropped overboard.

Planing Thin Sticks Held in Flooring Groove

Boys who make thin sticks for arrows, kites, etc., as well as the mechanic, can make good use of the following suggestion: The difficulty of handling thin strips while planing them may be overcome by setting the strip in the groove of a piece of flooring, clamped in a vise. A peg or nail is driven into the groove and acts as a stop for the end of the strip.

by Charles I. Reid]

Submarine photography should have great attractions for amateur photographers who have access to lakes, ponds, and other clear waters. While more careful work is demanded than in ordinary photography, the method of obtaining good results is not difficult, and the necessary equipment may be provided by constructing the device shown in the illustration. Submarine pictures can be taken in a considerable depth of water, providing it is reasonably free from foreign matter. This is a fascinating field of photography, and many pictures of educational and scientific value remain to be made of under-water life. The illustration shows the detailed construction of the camera chamber, and the method of suspending it from a bridge, or other place convenient to the body of water. Reproduced in the oval panel is a photograph of fish near baited hooks, on a fishline. The original was made from a negative exposed by the use of the camera chamber described.

The problem of making photographic exposures under water involves the provision of a strong water and pressure-proof container for the camera, a means for controlling the shutter, and a suitable opening in the container through which the exposures may be made. The arrangement described combines these features in a simple manner, and by the use of materials that can be obtained without difficulty. It was made for a camera taking 4 by 5-in. pictures, and the dimensions given are for a container for this size. The dimensions may be varied to adapt the device to various cameras, within reasonable limits. A 9-in. steel pipe was used for the chamber, and its ends were fitted with pipe caps. A heavy piece of plate glass was fitted into the forward cap, which was cut into the shape of a ring, to provide the exposure opening. The general arrangement of the camera in the chamber is shown in the sectional view, Fig. 1, as seen from the shutter end. The electrical device, by which the shutter is controlled, is shown in this view, and in Fig. 2 it is shown in detail.

The chamber was made as follows: A section of 9-in. steel pipe was cut to a length of 11¹⁄₂ in. and threaded on the ends to fit pipe caps. The forward pipe cap was chucked up in a lathe and the center portion cut away, to provide an exposure opening and a shoulder at the rim, on which the plate-glass window rests. A graphite paint was applied to the rim, then the glass was bedded solidly in it, and a rubber gasket was fitted to the joint, making it waterproof when the cap was drawn up tightly. The chamber assembled and in detail is shown in the illustration.

Holes were bored into the top of the chamber, and eyebolts were fitted into them. Between the eyebolts a hole was bored and fitted with a water-tight collar, through which the wires leading to the shutter-control device pass. The chamber is supported by the wires, which are fixed to the eyebolts and secured at the base of operations by the photographer.

A support for the camera was provided by bending a strip of ¹⁄₈ by 1-in. band iron to the shape indicated in Fig. 1, at A, and riveting it to the bottom of the chamber. Its upper surface is flat and was bored and threaded to fit the tripod thumbscrew B, on the lower surface of the camera. The camera is arranged on the support and clamped into place firmly by the thumb nut, as it might be on a tripod. The adjustment of the camera in the chamber is done from the rear, and the space beneath the thumbscrew should be large enough to make access easy. A camera of the size indicated, when fitted with its lens centering on the center of the window, will be raised sufficiently for convenience in clamping it. The threads on the back cap must fit snugly and no paint must be used on them. Hard oil, or vaseline, may be applied to insure a water-tight joint that permits easy removal of the cap.

The making and adjustment of the electrical shutter device requires care, but its operation is simple. An electromagnet, of the type used on doorbells, was fixed to the front of the camera, above the shutter, as shown in Fig. 1, and in detail in Fig. 2. It is actuated by current from two dry cells. The latter are kept in a convenient carrier at the base of operations, and are connected to the magnet by a single strand of double, waterproof wire. This is spread as it reaches the chamber and fastened to the two eyebolts in the top. The ends of the wires are conducted through the water-tight center opening between the eyebolts, and attached to the magnet. The release lever is fitted to a steel hook, pivoted at its upper end with a small nail, C, Fig. 2. A rubber band is fixed to the lower edge of the shutter lever and its other end is attached to the front of the camera. When the current is permitted to flow into the magnet by pressing a contact key, in the hand of the operator, the steel hook is drawn from the release lever, and the rubber band draws the lever down, making an exposure.

The double-wire cable carries the current as well as holds the chamber suspended in the water. The wire should be about 25 ft. long, and, in transporting the outfit, or when only partly used, is coiled. The chamber should be completed for picture-taking operations by giving it a coat of dull, black waterproof paint, both inside and outside. This will prevent rusting and also serves to make the object inconspicuous when in the water. It is important that the interior be painted in this manner, because reflections of light within the chamber may cause difficulty in obtaining satisfactory results. When the paint is thoroughly dry, the device may be tested for leakage and assembled ready for a test before making an actual trial in the water. The camera is fitted into the chamber so that it centers on the center of the plate-glass window, and is clamped into place. If the electrical device operates satisfactorily the plate may be inserted, the plate-holder slide withdrawn, the back cap replaced securely, and the outfit lowered into the water. It should be watched carefully until it reaches the proper depth, for, if it is permitted to touch the bottom, the sediment stirred up must be given time to settle before an exposure is made. The forward end of the chamber should be marked on its upper edge with a streak of white paint, to aid in identifying it at considerable depth in the water. This is important, since the operator must shift the chamber carefully until the window faces the objects to be photographed. When the chamber is in position, the contact key is pressed and the exposure is made.

The time of exposure for under-water photography depends on the clearness of the water, the depth at which the pictures are to be taken, and the light conditions on the surface. A bright day is, of course, desirable for this class of photography. A safe approximation on a sunny day, in clear water, and with the chamber lowered to a depth of 20 ft., is ¹⁄₂₅ sec. at the F 8 stop. The fastest plates or films obtainable should be used for this work, making possible a fairly rapid shutter speed. This tends to overcome the movement of the subject and possible movement of the camera.

The camera should be focused while in the chamber in order that the plate glass may not disturb the focus. The glass usually changes the focal length of the lens slightly, hence this precaution must be taken. The camera should be focused in the chamber for a distance of 10 ft., as this is the average at which under-water photographs will be taken ordinarily.

When attempting under-water photography in cloudy waters, or at a considerable depth, the necessary illumination may be provided by a charge of flash-light powder. For this purpose another submarine chamber, similar to that used for the camera, should be provided, with a plate glass, ¹⁄₂ in. thick, and a valve fitted into the top of the chamber, and opening outward, so that the gas may escape. Fifteen grains of powder will suffice, and this should be set off by a small electrical fuse connected to the current supply.

FIG. 2

Photographing Subjects under Water Is a Fascinating Diversion, and Each Exposure Has an Element of Mystery in the Uncertainty of the Result. The Photograph Reproduced in the Oval was Taken with the Outfit Shown. The Construction of the Chamber is Shown at the Middle. Fig. 1 Shows a Sectional Interior View, and Fig. 2, a Detail of the Electrical Shutter Release]

Every pond, lake, and river abounds in interesting and instructive subjects for submarine photography. Along the coast of Florida, and at many points along the Pacific coast, are waters of such clearness that pictures may be taken at a depth of nearly a hundred feet, without the use of artificial illumination. These localities abound in objects under water of great interest, such as shipwrecks. The fascinating art of taking pictures under water does not make it necessary for one to go to these places, for subjects are easily available. Whenever the submarine chamber is raised from the water there is an element of mystery involved, regarding what may be recorded on the plate or film, and this is an attractive feature of the diversion.

The Magic of Numbers

BY JAMES L. LANYON

That there are a great many magic squares; that the numbers in these squares are arranged according to a definite system; that squares with very remarkable properties are easily constructed, are facts not generally known.

Consider the magic square A of 16 numbers. Add up any four numbers straight across, up and down, or diagonally--10 ways in all--and the sum in each case will be 34. But that is not all: Take the four numbers in any one quarter of the square, as for example, 15, 10, 4, and 5, and the sum will be 34; or take the four central numbers, or the four corner numbers, and the result will be the same. But even this does not exhaust the magic of the square. Add any four numbers arranged symmetrically around the center, as 3, 10, 8, and 13, or 10, 4, 7, and 13, and the result will also be 34. In fact, it is really not necessary to have them arranged symmetrically, because it will be found that four numbers arranged as are 6, 10, 11, and 7, or 1, 4, 16, and 13 will produce the same magic number of 34.

There are two other combinations of the 16 numbers that will give the same result. They are shown at B and C. In fact the second one, B, not only exhibits some of the former combinations, but also includes such sets of four as 14, 5, 3, and 12, or 15, 8, 2, and 9, which places to the credit of this square numerous combinations. Such special features as this simply add another element of mystery and interest. Thus, while the square B has these two combinations exclusively to its credit, the first, A, and the third, C, have such special arrangements as 5, 16, 1, and 12, or 15, 6, 11, and 2. Also 10, 3, 5, and 16, or 4, 5, 14, and 11, making the total number of such combinations for the first square 34.

Magic squares of 25 numbers also have remarkable properties. Examine the square D and note the many possible combinations graphically set forth in the small diagrams. Not only do any five numbers in a row or along a diagonal make 65, but almost any four arranged around the center, with the center number 13 added, will give the same result.

This square is a good example by which to illustrate one of the methods of construction of these interesting devices. Thus, place 1 in the middle square of the top row, and then write the numbers down consecutively, always working in the direction of the arrows as indicated. When any number falls outside, as number 2 does at the start, drop down to the extreme square in the next row and insert the number there, as was done in this case. It will be observed that 4 falls outside, and so it is moved to the proper square as suggested, which will be at the extreme left of the next row above. Continuing, it is found that at 6 it is necessary to drop down one square and continue in the direction of the arrows. At 9 it is necessary to drop down to the proper extreme square as shown. The next number, 10, must again be provided for at the square on the left of the next higher row. The square ahead being already filled, 11 is placed below; after this there is “clear sailing” for a time. In this manner magic squares with seven or nine numbers to the side may be made easily. When puzzles and catch problems are under discussion, it is always mystifying to take one’s pencil and quickly make out a magic square according to this easily remembered method. The small diagrams at D suggest some of the combinations.

Another method of constructing a square of 25 numbers diagonally is shown at E. Place the outside numbers in the open spaces at the opposite side of the square, maintaining the same triangular relation, which results in the arrangement shown at F. While this combination is entirely different from the previous one, it exhibits the same mysterious properties.

+---+---+---+---+
| 15| 10| 3 | 6 |
+---+---+---+---+
| 4 | 5 | 16| 9 |
+---+---+---+---+
| 14| 11| 2 | 7 |
+---+---+---+---+
| 1 | 8 | 13| 12|
+---+---+---+---+
A

+---+---+---+---+
| 1 | 15| 14| 4 |
+---+---+---+---+
| 12| 6 | 7 | 9 |
+---+---+---+---+
| 8 | 10| 11| 5 |
+---+---+---+---+
| 13| 3 | 2 | 16|
+---+---+---+---+
B

+---+---+---+---+
| 9 | 7 | 14| 4 |
+---+---+---+---+
| 6 | 12| 1 | 15|
+---+---+---+---+
| 3 | 13| 8 | 10|
+---+---+---+---+
| 16| 2 | 11| 5 |
+---+---+---+---+
C

+---+---+---+---+---+
| 17| 24| 1 | 8 | 15|
+---+---+---+---+---+
| 23| 5 | 7 | 14| 16|
+---+---+---+---+---+
| 4 | 6 | 13| 20| 22|
+---+---+---+---+---+
| 10| 12| 19| 21| 3 |
+---+---+---+---+---+
| 11| 18| 25| 2 | 9 |
+---+---+---+---+---+

4 COMBINATIONS
6 COMBINATIONS

D

+---+
| 1 |
+---+---+---+
| 6 | | 2 |
+===+===+===+===+===+
‖ 11| | 7 | | 3 ‖
+---+---+---+---+---+---+---+
| 16‖ | 12| | 8 | ‖ 4 |
+---+---+---+---+---+---+---+---+---+
| 21| ‖ 17| | 13| | 9 ‖ | 5 |
+---+---+---+---+---+---+---+---+---+
| 22‖ | 18| | 14| ‖ 10|
+---+---+---+---+---+---+---+
‖ 23| | 19| | 15‖
+===+===+===+===+===+
| 24| | 20|
+---+---+---+
| 25|
+---+
E

+---+---+---+---+---+
| 11| 24| 7 | 20| 3 |
+---+---+---+---+---+
| 4 | 12| 25| 8 | 16|
+---+---+---+---+---+
| 17| 5 | 13| 21| 9 |
+---+---+---+---+---+
| 10| 18| 1 | 14| 22|
+---+---+---+---+---+
| 23| 6 | 19| 2 | 15|
+---+---+---+---+---+
F

+===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+
‖ 4 | 25| 18| 11| 7 ‖ 11| 24| 2 | 20| 8 ‖ 17| 6 | 5 | 23| 14‖
+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
‖ 14| 20| 2 | 17| 12‖ 9 | 12| 25| 3 | 16‖ 3 | 24| 12| 16| 10‖
+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
‖ 5 | 10| 13| 16| 21‖ 17| 10| 13| 21| 4 ‖ 11| 20| 8 | 4 | 22‖
+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
‖ 23| 9 | 24| 6 | 3 ‖ 5 | 18| 6 | 14| 22‖ 9 | 2 | 21| 15| 18‖
+---+---+---+---+---+---+---+---+---+---+---+---+---+---+---+
‖ 19| 1 | 8 | 15| 22‖ 23| 1 | 19| 7 | 15‖ 25| 13| 19| 7 | 1 ‖
+===+===+===+===+===+===+===+===+===+===+===+===+===+===+===+
G

+---+---+---+---+---+---+---+
| 30| 39| 48| 1 | 10| 19| 28|
+---+---+---+---+---+---+---+
| 38| 47| 7 | 9 | 18| 27| 29|
+---+---+---+---+---+---+---+
| 46| 6 | 8 | 17| 26| 35| 37|
+---+---+---+---+---+---+---+
| 5 | 14| 16| 25| 34| 36| 45|
+---+---+---+---+---+---+---+
| 13| 15| 24| 33| 42| 44| 4 |
+---+---+---+---+---+---+---+
| 21| 23| 32| 41| 43| 3 | 12|
+---+---+---+---+---+---+---+
| 22| 31| 40| 49| 2 | 11| 20|
+---+---+---+---+---+---+---+
H

The Magic Squares Shown Afford Much Interest to the Experimenter in Such Devices: The Mastery of the Principle Underlying Some of Them will Enable One to Mystify and Interest Onlookers, with Little Chance of the Simple Method being Discovered]

Although they do not contain quite so many combinations, the three magic squares shown at G all add up to this same magic number of 65, straight across, diagonally, and many other ways. A square with seven numbers to the side, worked out according to the first method described, is illustrated at H. The magic number here is 175. Since the general principle is similar to that involved in the squares described in detail, the working out of the numerous combinations of the squares shown at G and H will be left to the interested experimenter.

Muffling the Ticking of a Watch or Clock

When a watch is used on a table in the sick room, the ticking may be eliminated by placing an ordinary tumbler over the watch. The face may be seen readily. A large glass vessel, or transparent jar, may be used in the same way to cover a small clock.--L. E. Turner, Jamaica, N. Y.

* * * * *

¶To letter on prepared cloth, use colors ground in japan and thin the
mixture with gasoline to the consistency of cream.

A Simple Cipher Code

Adapted for Use in Private Correspondence

BY CAPT. W. H. WALDRON, U. S. ARMY

Have you ever needed a secret code in which to couch the contents of a message intended for the eyes of one person alone? If you have, you will remember the difficulties that were experienced in making up the code and enciphering your letter. Here is a cipher code that may be mastered in a few minutes; one that is most difficult to decipher by any person other than those having the key words, and that is very simple when once understood.

+---+---+---+---+---+
| G | R | A | N | T |
+---+---+---+---+---+
| | | | | |
+---+---+---+---+---+
| F | IJ| E | L | D |
+---+---+---+---+---+
| | | | | |
+---+---+---+---+---+
| | | | | |
+---+---+---+---+---+

FIG. 1

+---+---+---+---+---+
| G | R | A | N | T |
+---+---+---+---+---+
| B | C | H | K | M |
+---+---+---+---+---+
| F | IJ| E | L | D |
+---+---+---+---+---+
| O | P | Q | S | U |
+---+---+---+---+---+
| V | W | X | Y | Z |
+---+---+---+---+---+

FIG. 2

+---+---+---+---+---+
| C | H | A | IJ| R |
+---+---+---+---+---+
| B | D | E | F | G |
+---+---+---+---+---+
| K | L | M | Q | S |
+---+---+---+---+---+
| O | P | T | U | N |
+---+---+---+---+---+
| V | W | X | Y | Z |
+---+---+---+---+---+

FIG. 3

The Cipher Code Illustrated in These Diagrams may be Adapted for Wide Uses by the Substitution of Appropriate Key Words for Those Shown]

It is commonly known as the “Play Fair” code and is in use in some of the foreign military services. It is a substitutive cipher which operates with one or more key words, two letters in the code being substituted for each two letters in the text of the message. In preparing the cipher code by this method the key words are selected by the correspondents and their location in the cipher square mutually agreed upon. A large square divided into 25 smaller squares is drawn, as shown in Fig. 1, and the letters of the key words entered into their proper spaces, the remaining spaces being filled by other letters of the alphabet. The key words must not contain duplicate letters. The letters I and J are considered as one and entered in the same space, the letter I being invariably used in enciphering.

Suppose that the two words “grant” and “field” have been selected for the key, the same to be entered respectively in the spaces on the first and third horizontal lines of the square. Then the basis of the construction would be as indicated in Fig. 1. Now fill in the remaining fifteen spaces of the square with other letters of the alphabet, beginning at the blank space at the left of the second line, entering the letters in rotation and not using any letter of the key words. The completed cipher would then appear as shown in Fig. 2.

The text of the message to be sent is then divided into groups of two letters each and the equivalent substituted for each pair. Where two like letters fall in the same pair the letter X is inserted between them and when the message is deciphered this additional letter is disregarded. If one letter is left over after the last pair, simply add an X to it and make a pair.

Suppose it is desired to send this message in the cipher: “Will you meet me as agreed.” Having three pairs of the same letter, it will be necessary to break them up by placing the letter X between them. The message will then be paired off as follows:

WI LX LY OU ME XE TM EA SA GR EX ED

The message may now be enciphered, after considering three simple rules for guidance: Every pair of letters in the square must be either in the same vertical line; in the same horizontal line; or at the diagonally opposite corners of a rectangle formed by the smaller squares within the large square.

In the first case, R and P are in the same vertical line (the second), and the next letter below, in each case, is substituted for R and P, which are C and W. If the pair consists of K and Y (fourth vertical), substitute L for K and go to the first horizontal line (fourth vertical) for Y, substituting N for Y. In the second case B and H are in the same horizontal line (the second), and thus substitute the next letters to the right, which are C and K. If the pair consists of P and U (fourth horizontal), substitute Q for P and then go back to the first vertical line (fourth horizontal) and substitute O for U. In the third case, R and S are at the opposite corners of a rectangle. Each letter of the pair is substituted by the letter in the other corner of the rectangle on the same horizontal line with it. Then R would be represented by N, and S would be represented by P. To illustrate further, NE would be represented by AL; BZ would be represented by MV; TP by RU.

The message may now be enciphered, applying the rules:

WI LX LY OU ME XE TM EA SA GR EX ED
RP EY SN PO HD AQ MD QH QN RA QA LF

In sending this message, to make it more difficult for the inquisitive cipher expert, divide the substituted letters into words of five each and give him the added task of determining whether the cipher used is the transposition or the substitution method. The message ready to hand to the telegrapher would read:

RPEYS NPOHD AQMDQ HQNRA QALFX

In deciphering a message the method is reversed. Take the message as received, divide the letters into pairs, and disregard the final X, which was put in to make a five-letter word. Then apply the key reversed. Practice it on the above message to get the system with respect to letters occurring at the end of the lines. Where the letters of a pair are in the same vertical line, substitute for each the letter above; where they are in the same horizontal line, substitute the letter to the left; where they are in the corners of a rectangle, substitute the letters at the opposite corners on the same horizontal line. To test the understanding of the system, the message given in Fig. 3, with the key words “chair” in the first horizontal line and “optun” in the fourth line, may be deciphered. The message to be deciphered is as follows:

FQVUO IRTEF HRWDG APARQ TMMZM RBFVU
PICXM TRMXM AGEPA DONFC BAXAX.

Cheese Grater and Ash Tray Made from a Tin Can

Being in need of a cheese grater and finding it inconvenient to go many miles to town, I constructed a satisfactory makeshift. I took a heavily tinned can and cut it in two, as shown in the sketch. By punching holes through it from the inside a practical grater resulted. From the remaining half of the can I made an ash tray, as shown at the right of the sketch. The semicircular ends were bent over to form a rest, and by cutting portions at the sides and bending them in, a convenient rest for a pipe or cigar was afforded.--Gus Hansen, Peachland, B. C., Canada.

An Improvised Typewriter Desk

Travelers and others who carry typewriters on their journeys frequently find it inconvenient to use the tables provided because they are usually too high for typewriters. A method of overcoming this difficulty is to withdraw the drawer from the table and invert it in the slide as shown. The typewriter may then be placed upon the bottom of the drawer and will be considerably lower than if placed upon the table top.

An Inexpensive Imitation Fire

Window decorations may frequently be made attractive by the use of an imitation fire in a stove or a fireplace, when an indoor setting is on display. To produce such an effect, put an electric fan below the place at which the imitation fire is to be arranged and run an electric-light cord, with a red globe attached to it, to the center of the “flame.” Cut a number of strips of Indian red tissue paper and fix the lower ends of these to form a circular mass above the globe. When the light is turned on permit the fan to direct a stream of air against the tissue-paper ribbons, forcing them upward to appear like tongues of flame. The sketch shows this method applied to a heater. The fan is placed in the ash box and the electric light is conducted through the grate.

Jardinière Made of Metal-Lamp Body

Some of the metal bodies of old lamps, and they are usually brass, are of such ample size and so neatly embossed that they can be readily used as jardinières instead of being handed to the junk man. It is only necessary to remove the lamp part, and set the plant pot into the bowl of the stand, as shown in the sketch.--H. N. Wolfe, Chicago, Ill.

Replacing a Broken Coffeepot Knob

A knob was broken from the lid of a coffeepot, which was valued by reason of its associations. Attempts to fasten the broken portions together were unsatisfactory, and the rough surface, where the earthenware was broken, was ground smooth and fitted with a carefully shaped wooden knob. A hole was drilled through the center of the lid with an old file and the wooden knob bolted into place. When stained appropriately, the repair was quite satisfactory.

Homemade Magnesium Printer

A convenient homemade printing device consists of a smooth board, A, 2 ft. long and 1 ft. wide, and an upright, B, which is 1 ft. square. Bore a hole in the center of the upright for the small tin holder E, to carry the magnesium ribbon, made by folding a piece of tin to fit it. Small pieces of wood, CC, are nailed across the board to hold the ground glass D and the printing frame G. The ground glass is 10 in. from the upright, and the printing frame is 10 in. from the ground glass. The latter is 1 ft. square and is used to diffuse the light from the magnesium ribbon F, which may be purchased from any dealer in photographic supplies. The length of exposure varies according to the length of ribbon which is permitted to burn. This should be tested out carefully before making exposures.--Gustave Straub, Albany, N. Y.

* * * * *

¶In sandpapering a varnished surface between coats, especial care
should be taken to avoid rubbing through at sharp edges.

Garden Plow Made of Pick-Up Material

BY T. T. STURGEON

The labor of spading a garden of even moderate size is sufficient to warrant the person who undertakes the job in making a hand plow like that shown in the illustration, for it will serve many years, with reasonable care. I made one worth about $5 at an outlay of 25 cents, gathering the necessary wood and metal from among old machine parts and pick-up material.

An old wheelbarrow provided the 16-in. wheel. The handles were made from a ⁷⁄₈ by 4-in. strip of spruce, 5 ft. long. They were marked on the strip so that one of the curved grips was at each end, on opposite edges. The curved parts of the grips were cut with a keyhole saw, and when a kerf long enough to admit a large ripsaw was cut, the board was ripped into the two handles. They were smoothed and the grips trimmed with a sharp knife. A section of broomstick was cut for the upper brace. The lower one is made of a strip of iron, ¹⁄₄ by 1¹⁄₄ by 12 in., drilled for ¹⁄₄-in. bolts, and bent at right angles, 1¹⁄₂ in. from each end. Drill a ¹⁄₄-in. hole at the middle, to engage a bolt on which the vertical strip is supported, and adjusted to the operator, as shown in Fig. 1.

FIG. 4

FIG. 2

FIG. 5

FIG. 3

This Hand Garden Plow was Made of Old Material, a Shovel being Used for the Making of the Moldboard]

Cut a strip, ¹⁄₄ by 1¹⁄₄ by 18 in., for the vertical support, shown in Fig. 5. Drill four ¹⁄₄-in. adjusting holes, 1 in. apart, at the upper end, and three ¹⁄₄-in. holes at the lower end for fastening the strip to the moldboard, as shown in Fig. 3. Drill a ⁵⁄₁₆-in. hole at the 7¹⁄₂-in. mark, for bolting the strip to the braces, the other ends of which are fitted on the ³⁄₈ by 10-in. bolt used as an axle. Cut the two braces 14 in. long, of ¹⁄₄ by 1¹⁄₄-in. strips, and drill a ³⁄₈-in. hole in the forward end of each, to fit the axle, and a ⁵⁄₁₆-in. hole in the opposite ends, 1 in. from the ends in each case. Cut a strip, ¹⁄₈ by ³⁄₄ by 12 in., for the landside, as shown in Fig. 2, bent under the moldboard, and bolted to it. The proper angle can best be bent after the moldboard is made and fitted.

The method of marking the shape of the moldboard on the blade of an old shovel is shown in Fig. 4. Make a pattern of cardboard, marking it into 1-in. squares. Draw the shape of the moldboard by tracing the outline through the corresponding squares, using the diagram as a guide. Mark the position of the bolt holes, for fastening it to the vertical support, indicated by the dash lines at the right. Cut out the pattern and trace around it on the shovel, using the thickest part for the point of the share. Cut out the outline, smooth the edges, and point up the cutting edge. Drill holes for fastening the moldboard to the vertical strap with ¹⁄₄-in. bolts, and for the fastenings to the landside, with ³⁄₁₆-in. bolts.

Curve the moldboard into shape and fit it to the various supports so that it sits properly, as shown in Fig. 1, seen from the furrow side, in Fig. 2, from the rear, and in Fig. 3, from the land side. Bend the 12-in. strip into shape, as shown in Fig. 3, and bolt it into place, to form the landside. Assemble the parts, being careful that the wheel and landside are set in line, as shown in Fig. 2, and that the rear edge of the latter is raised slightly, as in Fig. 3. The plow should be given a coat of paint, and the cutting parts made smooth, and oiled.

An Interesting Water Telescope

A water telescope is easy to make and will afford much pleasure in exploring plant or animal life in comparatively shallow water. The device is made by fitting a heavy glass disk into the end of a round metal tube, about 2 in. in diameter. The glass is fitted between two rings of metal, preferably with a small flange set against the glass. A waterproof cement is used to fix the glass between the rings. To use the “telescope,” rest it on the side of a boat or other convenient place at the water, and set the lower end, containing the glass, under the water. Remarkably clear views may be had in this way.--S. Leonard Bastin, Bournemouth, England.

Writing on a Moving Train

Writing legibly on a fast-moving train is difficult to a person unaccustomed to it. The railroad conductor knows the trick of it and manages to get along quite satisfactorily. He prefers to write in a standing position and holds his right elbow firmly against his side. The reason for this is that in a sitting posture there is too much lateral movement in the trunk of the body, while in a standing position this is more easily controlled. When the arm swings freely, as in ordinary writing, several joints of the body are affected in the process, each of which is capable of its own motion. Holding the elbow against one’s ribs “breaks” these motion tendencies, except that of the wrist, which movement is necessary in writing, and thus the pencil, or pen, is more easily controlled.

The same principles modified apply in using a typewriter on a moving train. Many traveling men, news correspondents, and others, carry portable typewriters and do much of their writing while traveling on trains, not to mention the various railroad and government men who travel in office cars and necessarily must get out their correspondence en route. It is extremely difficult to execute neat typewriting on a moving train with free-arm movement, even though the central portion of the car where the vibration and swing is less severe, is selected. As I am employed in such capacity, I had to evolve some plan to expedite the work. I am able to do typewriting quite rapidly by resting the palm of the hands, near the wrists, against the front edge of the typewriter frame surrounding the keyboard, and using the swing of the fingers instead of that of the whole arm, as in ordinary typewriting.--Victor Labadie. Dallas, Tex.

A Revolving Window Display

A jeweler attracted passers-by and not a few customers by placing a revolving display in his window which was kept in motion by means of the arrangement shown in the sketch. A 10-in. cut-glass bowl was placed, upside down, near the front of the show window. An inverted tumbler was set upon it and a small tin box was pivoted on the tumbler by means of a needle soldered inside of it. Six arms of wire were soldered to the box, and watches were suspended from them. The carefully balanced frame revolved easily on the point of the needle. It was kept in motion by the draft from a fan hidden behind a mirror.--H. S. Hart, Shreveport, La.

A Horse-Drawn Sod Cutter

The cutting of a considerable area of sod is tedious work when done by hand, and it is difficult to make the sections of uniform thickness and size. These important features are provided for by the use of the homemade sod cutter shown in the sketch. To start a cut across a meadow or lot, a notch is cut in the turf for the blade, and the device is set into place, stamping it down to give a good start. The operator stands on the plank in front of the blade, and a little practice will soon determine the best position for ease in operation. When a cut has been completed, the cutter is dragged to a fresh starting place, the driver turning it over on the upper side. The strips are cut into suitable lengths and piled conveniently for removal with a stone boat or wagon.

The device may be made of any suitable width; 15 in. between the inner edges of the blade, and the latter set to cut a depth of about 2¹⁄₂ in., being desirable. The board is a 2-in. plank, about 4 ft. long. The blade should be set with the cutting edge slanting slightly downward so as to make the device “bite” into the ground. A smaller cutter may be made for use by boys, several of whom may draw it.--F. H. Sweet, Waynesboro, Va.

A Match-Box Trick