Popular Science Monthly
���How to Keep the Baby in His High- Chair
TO prevent a baby from standing up in his high-chair, try this: Remove the leather handle from an old razor strop. Cut a slit in the center from end to end, leaving about an inch at each end uncut. Fasten one end of the strop to the inside of the back of the chair, with 2 screws, ^ in. in diameter. Hook the other end up under the feeding shelf. The slotted belt rests comfortably on the baby's shoulders and he is perfectly safe. — Bernard Spivak.
A Substitute for a Condenser when Making Enlargements
FO R enlarging photographs under a r t i fi ci al light by the projec- tion process a good condenser, of di- ameter sufficient to cover the negative used, is necessary to insure even dis- tribution of light on the print. The object of the con- denser is, of course, to distribute the light more evenly to each and every corner of the nega- tive. A good sub- stitute for a condenser — lenses suitable for large negatives are expensive — is a lamp -board mounting a number of miniature tungsten bulbs so that the light is distributed fairly evenly over the whole surface of the negative, instead of being concentrated at a single spot, which is the case when a single lamp is used without a condenser. The board should be slightly larger than the nega- tive to be enlarged, and should mount as many lamps as it is possible to squeeze into the surface. If 6-volt lamps are
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used, 1 8 or 19 can be connected in series, to be used on the house-lighting circuit.
The lamp-board should be mounted well away from the negative at the free end of a bellows, so that the board can be kept in constant movement while the print is being made. This helps to distribute the light more perfectly. Ex- cellent results can be obtained with this simple apparatus. — E. F. Hallock.
A Wedge as a Burglar-Alarm
AN excellent burglar alarm for the home or for use when traveling is seen in the illus- tration. It Consists of a wedge, which is placed in the in- terior of the bedroom under the door. It carries several small points or claws on the under side, which grip on to the floor, making it impossible to open the door even by the hardest pressure. Be- sides, a bell rings when the device is pushed upon, for the wedge part slides back slightly upon the base, actuating a rod which sets off the bell mechanism. For use in hotels when traveling, the little device is one of the most practical, and, being small, it can be stowed in any baggage. No key is needed to wind up the bell. The bell itself is turned about by means of its milled edge as will be seen in the illustration. — F. P. Mann.
���An Easy Way to Remove a Chair-Leg
IT IS sometimes difficult when repairing chairs and other house- hold furniture to remove a broken end from the base, except by boring. If a screw-nail is driven into the broken end and tlicn a claw-ham- mer applied, the broken end may be removed very easily. — Jefferson Russell
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