How To Find The Horse Power That Any Wheel Will Transmit

(Pitch, ins.)2 X Breadth, ins. X Diameter, ft. X Revs. per minute / Appropriate No. according to speed, as above = Horse Power.

How To Find The Multiplying Number For Any Wheel

(Pitch, ins.)2 X Breadth, ins. X Diameter, ft. X Revs. per minute / Horse Power = Multiplying No. as above.

How To Find The Size Of Hole Necessary To Discharge A Given Quantity Of Water Under A Given Head

Cubic feet water discharged.

-----------------------------------------------------= Area of onfice, sq. in.

No. corresponding to height, as per table.

How To Find The Time In Which A Vessel Will Empty Itself Through A Given Orifice

√Height, feet surface above orifice X Area water surface, sq. ins.

Area orifice, square inch X 3.7

= Time required, seconds.

The above rules are founded on Bank's experiments.

New French Patent Alloy For Silver

Messieurs DeRuolz & Fontenay have invented the following alloy, which may be used for almost all purposes for which silver is usually employed: Silver, 20 parts; purified nickel, 28 parts; copper, 52 parts. Kelt the copper and nickel in the granular state, then introduce the silver. The flux to he employed is charcoal and borax, both in the state of powder; and the ingots obtained are to be rendered malleable by annealing for a considerable time in powdered charcoal.

How To Gild Steel

Pour some of the ethereal solution of gold into a wine glass, and dip into it the blade of a new penknife, razor, lancet, etc.; withdraw the Instrument, and allow the ether to evaporate. The blade will then be found covered with a beautiful coat of gold. The blade may be moistened with a clean rag, or a small piece of very dry sponge, dipped into the ether; and the same effects will be produced.

Muntz Metal For Ships

Best selected copper. 60 parts: best zinc, 40 parts: melt together in the usual manner, and roll into sheets of suitable thickness. This composition resists oxidation from exposure to sea water, and prevents the adhesion of barnacles.

Silvering Shells

Silver leaf and gum water a sufficient quantity; grind to a proper thickness, and cover the inside of the shells.

For a gold color, grind up gold-leaf with gum water, and apply t the inside of the shells.

Liquid Foil For Silvering Glass Globes, Etc

Lead, part; tin, 1 part; bismuth, 1 part: melt, and, just before it sets add mercury, 10 parts. Pour this into the globe, and turn it rapidly round.

How To Soften Iron Or Steel

Either of the following method will make iron or Steel as soft as lead:- 1. Anoint it all over wit! tallow, temper it in a gentle charcoal fire, and let it cool of itself 2. Take a little clay, cover your iron with it, temper in a charcoa fire. 3. When the" iron or steel is red hot, strew hellebore on it 4. Quench the iron or steel in the juice or water of common beans.