For the hub, solder or rivet a “handle” across the center hole and drill a hole through it of the same size as the center hole.  With the help of solder a grooved pulley which will answer almost every experimental purpose may be made, and it is remarkable with how slight care a perfectly true wheel may be made in this manner.

The same principle might in some way be applied to gear-wheels, for light and temporary use.  —­Contributed by C. W. Nieman, New York City.

** An Emergency Glass Funnel [412]

[Illustration:  Cutting a Funnel]

Secure a glass bottle having a small neck and tie a string saturated in kerosene around the outside at A and B as shown in the sketch.  Light the string and allow it to burn until the glass is heated, then plunge the bottle quickly into water.  The top or neck will then come off easily.  The sharp edges are ground or filed off smooth.  This will make a good emergency funnel which serves the purpose well for filling wide necked bottles.  —­Contributed by Jos.  W. Sorenson, Everett, Wash.

** An Electrical Walking Stick [413]

A cane that will produce an electric shock when shaking hands is one supplied with the electrical apparatus shown in the sketch.  An ordinary cane, 1 in. in diameter at the top and having a metal band A, is bored about 8 in. deep, to receive the battery B and induction coil C. One of the electrical connections is through the metal tip D to the earth, the other is through the

[Illustration:  Battery and Coil In Cane]

metal band A when the push button E is pressed.

The one using the cane merely holds the metal end D in contact with the earth and while shaking hands with a friend he pushes the button and starts the coil in operation.  —­Contributed by Stanley Radcliffe, Laurel, Md.

** Convenient Shelf Arrangement [413]

A convenient device for crowded shelves and cupboards is shown in the accompanying sketch.  Halfway between shelves A and B is installed a second shelf C which is only half as wide as the other shelves.  This

[Illustration:  Shelf]

provides a convenient place for small articles and utensils, while in a china closet it furnishes a splendid space for cups, sauce dishes or other small pieces.  It also adds a neat and pleasing appearance.  —­Contributed by E. M. Williams, Oberlin, Ohio.

** A Shoe Scraper [413]

On steps of public buildings, shops and dwellings is usually found some sort of a mud scraper for the shoes.  These remove the mud from the sole of the shoe and leave it on the edge and sides.  The scraper shown in the sketch is of simple construction, and removes the mud from the soles and

[Illustration:  Scraper of Thin Steel]

sides of any size shoe in one operation.  The scrapers spread and bring pressure to bear on all sizes.  The side scrapers must be made of metal that will spring.  The standard is of heavy sheet metal with the thinner strips riveted to the projecting uprights at the ends.