As a means of pleasant and interesting entertainment, a well made magic lantern possesses many attractions to the amateur, and this is especially true if several friends also have lanterns, the exchanging of slides serving to give sufficient variety to sustain interest through many evenings. In addition, the multitude of slides which may be hired or purchased, open up a wide field, limited only by the capacity of one's pocket book or inclinations.

The lantern here described, while made for home use, requires no change, other than the objective, to adapt it for large halls,. and two of them with a dissolving attachment would equal in worth that of an expensive lantern. The sizes of the condenser and objective as given in this lantern can be charged, if necessary, to other approximate sizes, and the reader is advised to purchase these before constructing the lantern, that he may know their exact dimensions and work accordingly. These sizes specified were purchased of a dealer over stocked on these sizes and because of a substantial reduction from regu lar prices. Readers in large cities are advised to visit the different optical and photographic supply houses, as by so doing they may be equally fortunate in securing a bargain. For house use, a wide angle or small lens is necessary, as the size of the picture thrown on the screen depends upon the size of lens and distance between lens and screen as shown in the following table, giving the various sizes of pictures to be had with different objectives at varying distances from the screen when three-inch slide is used.

Sizes of Distance from Screen.

Lenses 10£t. 20 ft. 30 ft. 40 ft. 50 ft. 60 ft.

The several parts of the lantern include the objective or lens, and holder for same, focusing tube, slide box and frame, condenser and holder, burner and hood and adjustable framework, which will be separately described. The frame is made almost entirely of brass castings and tubing, the patterns for the castings being easily made from pine.

The shape and dimensions of the objective support are shown in Fig. 1. The casting A is finished with a file and fine emery cloth. The holes a are " diameter, pieces of 22 guage tub-ing 8" long, being secured therein at one end by soldering. The guides C are made from a piece of 5/8' 'Square brass tubing 5" long, which has been split centrally, the lower ends being double riv-ited to the casting A. The slots b, 3" x 3/16" are worked out with a small flat file, after drilling holes at each end with a hand drill and sawing down with a hack or heavy fret saw. The objective has a threaded flange which is mounted centrally upon the block D, Fig. 2, made of mahogany and nicely polished. It is 5" square and 3/4" thick, the sides fitting into the guides (7, being cut down with a rabbet plane to an easy fit. At the centre of these sides, brass pieces d 2" long, 5/8" wide and 3/16" thick are let in, after drilling and tapping holes in the centre for 3/16" knurled head brass set screws. These are needed to adjust the lens to the correct position to throw the picture evenly on the screen. The usually focussing arrangement of a lantern is a bellows much like those used in cameras, but this requiring considerable time to make and the use of materials not easily obtained, a telescopic tube was used, this being made from a one pound coffee tin for the outer tube and the inner one from a re-soldered tomato can. The latter was heated along the seams over a furnace fire until they separated, then cleaned and re-soldered to an easy sliding fit to the other can. This gives ample adjustment. The condenser cell was made in the same way, with the exception that the case of an old alarm clock was used for one section, and a coffee tin for the other, the length of each having to be cut down to the dimensions given later. The ends of the cans were cut out to give a flange about 1/8" wide. First mark with ' dividers, if an old pair is available, sharpen one point and use to cut through by continued working around the line. With a lathe, mount on face plate with wood backing and cut with hand tool. A coat of black enamel paint will give a good finish. One tube is attached to the piece D by four short round head screws, the heads of which lap over the flange, the location being marked by striking a circle with dividers after the frame is completed so that the parts will not bind anywhere. The other tube is riveted to the slide holder support S, Fig. 3. Suitable rivets are made by cutting off the ends of brass escutcheon pins, filing the ends smooth. The heads are on the inside of the tube, held during riveting against the top end of a cold chisel or piece of bar iron held in a vise.

The slide holder support is made of a strip of sheet aluminum, 16 guage or thereabouts, 14 1/4" x 6". The faces are 6" square, the ends 7/8" and the lap for the joint 1/2". The turns are marked with a scratch point then bent carefully to shape. If convenient, take to a tin shop and have the bending done on a machine. The circular openings in each face are cut out before bending. This can also be done at the tin shops at little or no expense, and a better job secured than ordinarily if done by the reader. The size of the holes cannot be determined exactly until the condenser cell is completed, so this part should be left until after making the condenser. A piece of 9/16" tubing S', 4" long is attached to each lower rear corner of the holder, by first sweating on strips of brass S", the ends of which are turned outward to form lugs for riveting to the holder, as owing to the nature of aluminum, they cannot be soldered to it. The final length of these pieces is found when the frame is completed, they are then cut off to bring the rear hole in the holder in line with the condenser.

The remaining part of the frame is now to be made. Three brass castings F, F', F" Figs. 4 and 6, are required. These are finished by filing and with fine emery cloth. Holes are then drilled for the 9/16" brass tubing G, 22 guage which must be in exact line with the tubes in the holes in A, as these tubes slide within each other. The rods G are 5" long, and are sweated into the holes drilled in F and F'. Other 9/16 holes are then drilled in all these pieces F for the rods G' which are 12" long. These are sweated in, but care should be taken to have the brass casting H, Fig. 6, finished, fitted and in place before this is done. This casting has 9/16" holes drilled in line with the tubes G' and slides freely thereon. Two pieces of 1/2" brass tubing h, 4" long, are fitted to holes drilled in H and spaced to fit the pieces of 9/16" tube S" on the slide frame holder. Knurled head set screws j are fitted to each end of Hand also to F as shown at f Fig. 5, for fastening the rods B.