Popular Science Monihly 



473 



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 

 automaticallv. — F. A. Wilhelm. 



BICYCLE 



SPROCKET 



A Pull on the String Supporting Lighter 

 Weight Opens the Plug 



