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Page:Popular Science Monthly Volume 89.djvu/948

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��Popular Science Monthly

��A Dark-Room Lamp to Be Used Under a Glass Tray

THE lump illuslrated is a very handy instrument for developing plates and films. It consists of a light-tight wood box A containing a small lamp B and a reHector C. The size of the ruby -6'

���A and should be glued to that board. With reasonable care the batteries will last at least a \ear and the amateur photographer will find that the negatives are far better developed in this manner. Roll films can be developed in the same manner as plates by attaching them to a glass plate of the same size as the film, using rubber bands to hold it closely to the plate surface. — V. A. Oi.drovd.

��The developing tray of glass is placed on top of the ruby glass of the lamp

glass D depends upon the size of the plates used. There are two dry bat- teries E, about 6 in. long by 2 in. in diameter which supply the current for the lamp. The circuit is opened or closed by the switch F. Two wood blocks H keep the batteries E in their proper place and support the reflector C. The developing dish must be of glass and is placed on the ruby glass D. The dry plate or film is then put in the dish, the developer poured on and after about half a minute the lamp B ' on for a few seconds. Without 1 the plate out of the dish one judge the development as the li is thrown through the ruby gh D, and through the bottom of th developing dish and the nega- tive. This is repeated until development is complete

Since the dark- room lamp described here is the only source of light in the dark-room, and is used only at inter- vals for a few seconds, there is no po.ssibility of ft)g.

The dimensions given refer to a lamp for plates 4 by 5 in. The reflector C may be Ck-rman silver aiifl about 1/32 in. thick and fasteiuij In tin- wcickI blocks H. The dr\- cells are connected in series. The niiiy glass I) fits in a recess in tln' top nf liie board of the box

��A Sanitary Honie-Made Tooth-Brush Holder

PROCURE a small bottle and fasten to its lower part a wire hook with an elec- tric or rubber band. The hook is used for hang- ing the bottle to the wall in a con- venient place. The tooth-brush is forced through

���The toothbrush is forced through the neck of the bottle

���the neck, which holds it until needed for use. The bottle is hung in an inverted position. — J.4MES E. Noble.

A Fountain Attachment for

Ordinary Pens

��fIG 2

��AN ordinary pen . can be made

��The coil of wire makes fountain for an ordinary

��into a fountain pen quite easily by at- taching a small foun- tain made of wire.

To make this fountain wrap a piece of fine iron wire around the point of a sharp pencil as shown in Fig. 1 , leaving about J4 in. straight. To fasten it to the pen, wraji the straight wire around the pen- shank. The coil part is fitted into the inulerside or IkiHow i)arl of the pen with the pointed end down, as in Fig. 2. The coiled jiart forms a pocket fpr linlding the ink which is fed to the pen betwt'en the coils. The dipping of the pen in the ink fills the coil. This foinitain will hold .1 good i|ii.mlil\- of ink.

��the pen

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