How To Remove Blue Color From Steel

(1) Use 1 part oil of vitriol to 10 parts water. (2) Dip the articles in a strong solution of cyanide of potassium nearly boiling. (3) Dip the article in hydrochloric acid, and quickly rinse in clean water.

Tempering Steel For Drilling Rock

Be careful not to overheat it in hardening and forging, and quench in salt water, drawing to a brown color.

Tinning Small Castings

Clean, and boil them with scraps of block-tin in a solution of cream of tartar.

Steps For Water-Wheel

No step or foot-bearing of metal is equal to one of good oak or rock-maple.

Stamping Zinc

In stamping sheet-zinc in dies, much waste occurs from the small difference between the melting-point and the temperature at which sheet-zinc should be stamped to get the best effect. To obviate this waste, heat the zinc by dipping in oil at the proper temperature.

Engine For A Row-Boat

For an ordinary Whitehall row-boat, 18 feet long, to run at a speed of 8 miles per hour, the engine should have two cylinders, 2 in. diameter and 3 in. stroke; tubular boiler, 24 to 28 inches in diameter, 4 feet high; propeller, 22 to 24 inches in diameter, with 3 feet pitch.

Exhaust Steam

This should not be discharged into a brick chimney. It is liable to disintegrate the mortar and destroy the chimney.

Thickness, In Inches, Of Flat Heads (Not Stayed)

Multiply the square root of the pressure in lbs. per square inch by the radius of the shell in inches, and by 0.013333 for a head of copper; by 0.010541 for a head of wrought-iron; and by 0.0081649 for a head of steel.

A steel boiler has a diameter of 24 inches, and the pressure of the steam is 60 lbs. per square inch: The thickness of the head is the product of 7.746 (the square root of 60), 12, and 0.0081649, which is equal to 0.7766, or about 25/32 of an inch.

Priming In Boilers

If your boiler primes, either "swap" it off for another or superheat your steam moderately; but beware of anti-priming doctors and their remedies.

Fire-Clay For Boiler-Furnaces

Take common earth, well mixed with water, to which is added a small quantity of rock-salt; let the water stand until the salt dissolves, which will take about 2 or 3 hours. It is then ready for use. Apply it as fireclay is used, and your furnace will stand much longer.

How To Calk Leaks In Flue-Sheets

Use a reflector (a tin plate will do) adjusted in front of the furnace-door, so as to throw light on to the flue-sheets, while calking leaks.

Keeping Clean Mercurial Steam Gauges

This can be done by putting a little glycerine or sulphuric acid on the surface of the mercury. This serves as a Lubricator of both glass and metals, and prevents their adhesion.

Effect Of Steam On Lead

Lead in contact with steam under pressure of over 10 lbs. per square inch very soon loses its strength, and it is therefore good neither for packing joints nor for conveying steam.