FIRE EXTINGUISHEIto AND FIRE ESCAPES To Extinguish Fires.—The objects to be attained in putting out fire are principally two: to cut off its source of supply in the oxygen of the air, and to lower the temperature of the burning substances below the point of combustion. Drenching the burning parts with water accomplishes both objects. It prevents the access of air and chills the burning parts.
A heavy woolen cloth thrown over or wrapped about burning objects smothers the fire by shutting off the air, and if wet, also assists by lower ing the temperature.
Chemical fire extinguishers produce noninflammable gas, as carbon dioxide, which flows over the burning parts the same as water, temporarily shutting off the supply of air; hence the fol lowing suggestions for extinguishing fires: Close the doors and windows to pre vent draughts. Seize the burning ob jects if small and movable, as lamps, curtains, and the like, and throw them out of the window, or wrap them in rugs or woolen table covers or bed covers.
Or, if solid, heavy objects are on fire, seize a woolen blanket or other heavy woolen article, and if possible beat out the flames. If a small quan tity of water is at hand, dip the woolen cloth into it and beat the fire with that. A single pail of water will go further if soaked up in a blanket than if dashed directly on the flames.
Or, if plenty of water is at hand, dip a mop in it and beat the flames, or dash it on the fire in small quanti ties from, a dipper, directing it in telligently to cover as much space as possible.
To Put Out Burning Garments.— If d person's clothing takes fire, he should be rolled up in a woolen rug, overcoat, table cover, or blanket to smother the fire.
Or, if alone, he should roll himself up in one of these articles as quickly as possible; roll over and over on the floor or bed; or tear up the carpet and roll up in that.
To Extinguish Fire with Chemicals. —To make a chemical fire extinguish er, prepare a mixture of substances that will produce carbonic-acid gas in the presence of water, and arrange so that a stream of mingled gas and water will be thrown upon the flames by the expansive power of the gas. This is the celebrated patent of Will iam A. Graham of Lexington, Va.,
that was contested during nearly fifty years in the United States courts. It is the principle of most chemical fire extinguishers now upon the market.
The substances most commonly mixed to produce carbonic-acid gas are common soda and sulphuric acid, or oil of vitriol. Numerous practical devices have been patented for stor ing these two, or other substances, in a suitable receptacle side by side, but so arranged that they will not mingle until wanted. Then, by turning the receptacle upside down, or turning a stopcock, the acid is precipitated into a solution of bicarbonate of soda in water and the water is thereby charged with carbonic-acid gas, which, by its expansive power, ejects the stream of mingled gas and water through a flexible rubber tube and a nozzle.
One device consists of a tank or jar containing a strong solution of bicar bonate of soda or common baking soda in water in which is immersed a tightly stoppered bottle containing oil of vitriol. The stopper of the bottle may be pulled out by means of a wire running through the cover of the tank, thus allowing the acid to mingle with the soda solution and produce car bonic-acid gas. To imitate this device, take an old milk can or a five-gallon oil can and have a tinsmith fit it with a screw top and a stopcock fitted with a flexible rubber tube and a nozzle. Plain rubber tubing or flexible gas pipe is suitable for this purpose. The longer, the better. Fasten to the re movable screw top by means of wire a glass bottle containing sulphuric acid and having a glass stopper. Fas ten another wire about the neck of this stopper, let it protrude through the cover, and end in a ring.by means of which the stopper may be with drawn. But care must be taken to use wires strong enough so that, should the stopper stick, the bottle may be broken off if need be without remov ing the screw top of the can. When required, carry the extinguisher to the vicinity of the fire, pull out the stop per, and shake the can to mix the oil, and soda solution. Turn the stop cock and direct the resulting stream of water charged with carbonic-acid gas upon the flame.