Page:Popular Science Monthly Volume 89.djvu/487

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Popular Science Monihly


��Cheap Photographic Changing Box

PII () T () G - RAPHERS who adopt the tank method of development and so dispense with all the trouble incidental to the older method, can very well do with- out a dark room excejit for the pur-

���Plates Can Be Handled in Broad Daylight

��pose of loading and unloadint; the plate luiliiers. By means of the box illustrated on this page, plates can be handled both before and after exposure with perfect safety in daylight, a dark room being entirely unnecessary.

The box should be oblong, and may be made of thin wood or cardboard. The writer has found a hat box satis- factory for a 4-in. by 5-in. plate outfit, and has in fact used such a box for years. A swing back lid, opening above is the best type. Two circular holes must be cut in one of the sides, large enough to admit the hands easily. A couple of short sleeves, made from black twill (double thickness) must be sewn over these holes securely with stout thread.

The bo.x must be made thoroughly light-tight by covering both inside and out with black cotton lining, to be purchased at a dry-goods store. The corners and the angles formed by the sides should be strengthened with ad- ditional strips of the same material, because pinholes are more likely to develop here than elsewhere. A ring of black cloth must also be glued o\cr each of the holes over which the sleeves were sewn, so as to cover any small holes left by the needle.

Particular care must be taken to make the lid fit light-tight. In the case of a hat box the lid is always loose fitting and there is plenty of room in which to sew a piece of black cloth, folded twice, all around the edge of the box. A very simple device may be used for keeping the lid closed while in use. h brass paper fastener should be passed through the side of the box and another through the lid. A few inches of stout thread! with a button attached should

��be tied round the former, the thread being passed twice round the head of the upper fastener to close the lid. 1

All the plate holders that are to be filletl and the unopened packet of plates (or the plate holders after exposure and the developing tank), must be put into the charging box before closing the lid.

A damp sponge can be kept in a small saucer in the corner of the box for moistening the finger tips, when by touching the extreme corner of each plate, the gelatine will be felt to be sticky. — H. J. Gray.

An Automatic Faucet for Tanks

AN automatic faucet may be con- . structed by anyone with the proper pipe-fitting tools.

In the drawing a bic>cle sprocket is screwed on to the shank of an ordinary spigot-plug which has been previously threaded to receive it and a lock-nut.

A piece of bicycle-chain is shown on which are suspended two equal weights the former of iron or any heavy material and the latter of wood or something buo>'ant. To open the faucet the string supporting the W'ooden weight is pulled down, turning the sprocket to the left and opening the plug. As the water ap- proaches the top of the tank the wooden weight is raised on the surface, allowing the other to descend, closing the spigot automatically. — F. A. Wilhelm.



���A Pull on the String Supporting Lighter Weight Opens the Plug

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