The Optical Magic Lantern Journal (May 1901)

The Optical Magic Lantern Journal and Photographic Enlarger. works independently of the other parts of the body. The arm marked 4 is pivoted to the loop in the wire © and to the body. The leg 5 is soldered to the wire F and pivoted to the body as well, whilst the other leg 2 is pivoted to the hip ‘8 and soldered to the wire Er. The constructions of this figure may seem at first sight somewhat difficult, but the reader, if he compares the two diagrams, will find everything explained. Jt is: obvious that as the wires EB F, presenting the ropes, move in their proper course, the distance between the various points at which the different parts of the body are pivoted will vary, causing the desired movements of the swinger. When this part of the work has been carefully done the reader may turn his attention to the sliding glass a (Fig. I.), which is cut to the shape shown, and which On glass A a small wooden block is fastened by means of glue—a sectional view of this is given in Fig. V.—and to the block is fixed a pin, consisting of a screw with the head filed off flush with the surface of the wood. This block is also shown in Fig. IV. Reference now being made to Fig. VII., we have here a view of the back side of the slide. The portions rR and q are fixed by means of screws and are therefore detachable. Their inner edges are bevelled off as shown in the sectional view (Fig. VIII.), so that the glass on which the model is mounted may be easily removed; a convenience in case any one part should happen to get out of order. When the fixed glass p has been properly fitted up, the block, q or R, is taken off, and the glass carrying the block « (Fig. IV.).slipped into the groove. It is important to observe that the actual glueing on of the block. carrying the pin is left to the last moment, so that the pin may be placed into its proper position before the glue on the block has entirely set. re| The. detachable. ' 14 dram, ammonia 2 drops. block, which has been removed, may then be replaced, when the slide is ready for use. When it is placed in the lantern for exhibition, the sliding glass is pulled half-way out, so that the figure appears to be at rest; then it is pushed in and out, with a gradual increase in the distance of each successive movement. When it has reached the limit set by the two blocks it is kept at the same rate for a few moments, then gradually slowed until the swinger is once more at rest. =O we Blue Lantern Slides.* By BASIL DONSETT. YF oO, FH 34 HE most important point of all is to 2 2 clean the glasses thoroughly. These oS may be either patent plate or other good cover glasses purchased new, or they may be old lantern slides. cleaned off. If they are the latter, my: modus operandi is as follows :— I take the slides and, placing them in a grooved washing trough so that they are kept separate from one another, I allow them to soak for 24 hours in cold water. I then prepare a solution of washing soda—tz lb. to the quart of boiling water—and put the slides in this one at a time until they are all covered. They remain in this for a quarter of an hour or more until cool, when they are taken out one at a time, scrubbed on both sides with an ordinary scrubbing brush, and rinsed in cold water. They may then be dried and treated in the subsequent operations just as new glasses. ; The new glasses are rubbed over with a tuft of cotton wool moistened with a cream made by mixing whiting to a suitable consistency with water 1 ounce, alcohol (not methylated) This is smeared over both sides, and the plates stood in a rack until dry. Two clean cloths are then taken. With the first as much as possible of the whiting is wiped off, giving particular attention to the edges, and then with the other the glass is well polished and stood in the rack to await coating. Care must be exercised not to finger the glass after cleaning. ; . A levelling table is next required. Mine is very simple, and is made afresh every time it is used. Three French nails are driven into a working bench 2 or 3 inches apart until they stand firmly, making a little triangular tripod. . “Exchange ” in the Photo-American.