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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763 



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 



Broken 



