Potassium Bichromate  15 gr. 
Magnesium Sulphate    25 gr. 
Water                  1 oz.

This mixture is spread over the paper in the usual way and the paper dried in the dark.  Printing is carried rather far.  The print is washed, then surface dried or blotted off on a pad and laid film upwards on a sheet of glass, and the following developer is applied with a wad of cotton wool wrung out: 

    Pyrocatechin 5 gr. 
    Water 1 oz.

The picture assumes a rich green color when developed, and is then washed for five or ten minutes and dried quickly by heat.

** Copies Made from Wax Molds by Electro-Deposition [157]

Fine copies of wax impressions can be made in the following manner:  Procure an ordinary tumbler and fill it with a strong solution of sulphate of copper, which is made by dissolving two cents’ worth of blue vitriol in 1/2 pt. of water.  After this is done make a porous cell by rolling a piece of brown paper around a stick and fastening the edge with sealing wax; also, fix a bottom to the cell in the same way.  Make a solution of one part of oil of vitriol and 5 parts of water and pour this mixture into the porous cell.  Wind the end of a copper wire around the end of a piece of zinc and place the zinc in the porous cell.  Attach the other end of the wire to the wax impression.

The wax impression is made by pouring melted beeswax on the article you wish to reproduce and removing after the wax gets cold.  The wax mold then should be coated with black lead and polished.  This is done with a camel’s hair brush.  A fine copy can be made on the wax impression after the battery has been running about 12 hr.  —­Contributed by Edward M. Treasdale.

[Illustration:  Electro-Deposition]

** How to Make Skating Shoes [158]

Remove the clamp part, as shown in Fig. 1, from an ordinary clamp skate.  Drill holes in the top part of the skate

[Illustration:  Skating Shoes]

for screws.  Purchase a pair of high shoes with heavy soles and fasten the skates to the soles with screws, as shown in Fig. 2.  When completed the skating shoes will have the appearance shown on Fig. 3.  These will make as good skating shoes as can be purchased, and very much cheaper.  —­Contributed by Wallace C. Newton, Leominster, Mass.

** How to Make a Self-Setting Rabbit Trap [158]

Secure a good-sized box, say, 1 ft. high, 1-1/2 ft. wide, and 3 ft. long; and to the bottom, about 10 in. from one end, fasten a 2-in. square piece, A, Fig. 1, extending the width of the box.  Place a 10-in. board sloping from the end of the box to the cleat A. The swing door B, Fig. 1, is made as shown

[Illustration:  Self-Setting Trap]