Page:Popular Science Monthly Volume 92.djvu/298

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��Popular Science Monthly

��A Homemade Focusing Hood for a Hand Camera

THE plate camera, although a little slower to arrange for procuring a pic- ture, will usually give better results than other kinds, owing to the fact that it can be brought into perfect focus, by adjusting

����A hcx)d for the camera back for keeping light from ground glass while focusing

the image shown on the ground glass.

The greatest difficulty in doing this has been in cutting off the side lights. This is usually done with a cloth thrown over the head, which method is uncomfortable and slow.

The hood, shown in the illustration, can be attached very easily and can be tele- scoped small enough to carry conveniently in the pocket or case. First, cut four pieces of paste-board about 2 in. in width and long enough to fit around the frame of the camera. Two of these pieces should be slightly shorter than the others. Sew the four pieces together to form the frame. In pulling the joints together, at least 1/16 in. should be left to allow the frame to fold when placed in the pocket. A piece of black oilcloth is then procured and cut according to the pattern shown. White oilcloth may also be used just as successfully.

After stitching the V-shaped edges to- gether, the shape is pyramidal. Now place the larger opening over the paste- board frame, allowing it to lap about 1 in., and sewing it firmly to the frame. Fasten a wire around the opposite or smaller opening, and hem the oilcloth over the wire.

��When this hood is placed over the cam- era, the door of camera can be opened back into it, allowing a perfect view for focusing. — Chas. Claude Wagner.

��An Indestructible Paper Weight and Blotter

A BLOTTER and paper weight which is practically indestructible, can easily be made by mixing 7 parts (by weight) of gypsum, one part of potato flour and a small portion of water. Just enough water should be used to dampen the mixture. The ingredients should im- mediately be poured into a well greased mold, and there allowed to dry thor- oughly. Then they will be quite ready for use. — W. S. Standiford.

��Making Bone Black from Scraps of Leather

THE apparatus illustrated is for the purpose of manufacturing bone black — animal charcoal or ivory black, as it is called. I have made this pigment for black shoe polish or paste, discoloring liquids, filtering, etc.

It consists of an ordinary piece of pipe — the size depending on the amount to be heated, or burned — capped on one end, with the other end left open to make it convenient for filling and to provide escape for the gases. The pipe is half filled with scraps from old shoes and har- ness. The filled pipe is then laid with the capped end in a furnace or in the fire- box of a stove, allowing the open end to extend out where the gases coming from

��.Pipe cap

���Leathei' scraps

��Gases burn as •they come out

Arrangement of a pipe for burning leather scraps to make an ivory black pigment

��the pipe will burn during the operation. The animal charcoal obtained from the leather scraps is free enough from any mineral substance to need no acid treat- ment whatever. — Henry Klaus.

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