** A Book Rest [292]

A book that does not open flat is rather inconvenient to write in when one of its sides is in the position shown in Fig. 2.  A wedge-shaped piece of

[Illustration:  Book Back Holders]

metal, stone or wood, as shown in Fig. 1, will, when placed as in Fig. 3, raise the sloping half to the level of the other pages.  Cover the block with rubber, wide rubber bands or felt, to prevent its scratching the desk top.  The block can also be used as a paperweight.

** Window Shelf for Flower Pots [292]

On the ledge formed by the top part of the lower sash of the window I fitted a board 7 in. wide into each side of the casing, by cutting away the ends.  I placed a small bracket at each end of the shelf, so that it would fit solidly against the lower window sash to support the weight of the plants.

[Illustration:  Shelf in Window]

One of the brackets I nailed to the shelf and the other I held in place with a hinge, the reason being that if both were solid, the shelf could not be put on the window, as one end must be dropped in place before the other.  Such a shelf will hold all the plants a person can put on it.  When not in use, it can be removed without marring the casing.  —­Contributed by G. A. Wood, West Union, Ia.

** Magnet for the Work Basket [292]

Tie a ribbon or strong string to the work basket and fasten a large magnet to the other end.  Needles, scissors, etc., can be picked up without any trouble.  This device is very convenient for invalids.  —­Contributed by Nellie Conlon, Worcester, Mass.

** Knife Made from a Hack-Saw Blade [293]

A very serviceable knife with excellent cutting qualities can be made easily from a discarded hack-saw blade.  The dimensions given in the sketch make a knife of convenient size.

The saw teeth are ground off on an emery wheel or grindstone to a smooth edge parallel with the back edge.  For the handle, take two pieces of hard wood, dressing one surface of each piece, and cut a groove as wide and thick as the saw blade.  Place the blade in the groove and glue the two dressed sides of the wood together.  After the glue has dried, the blade can be pulled out of the groove and the wood shaped to any desired form.  A small wood-screw is put through one side of the handle to prevent the blade from sliding.  After completing the

[Illustration:  Details of Handle]

handle, the blade is put back into the groove and sharpened to a cutting edge.  —­Contributed by H. A. Hutchins, Cleveland, Ohio.

** Killing Mice and Rats [293]

A simple and inexpensive means for killing mice and rats is to leave yeast cakes lying around where they can eat them.  —­Contributed by Maud McKee, Erie, Pa.

** Roller Coaster Illusion Traveling Up an Incline [293]

A toy car with a paddle wheel and a shaft on both ends traveling upward on a chute in which water is flowing down, is shown in the accompanying sketch.  The paddle wheels travel in a reverse direction causing the ends of the axles to roll on the edge of the chute, thus carrying the car up the incline.  If a rack is used on each side of the chute and a small pinion on the