The conclusion reached from these and many more experiments was that the Harden grenade solution possesses _much greater_ extinguishing power than water alone, and that it owed this power to common salt held in solution. We then constructed some home-made grenades, using flat bottles bound together side by side with wire. Using two bottles in this way insures their being broken in striking the burning body, which would not always occur when only one bottle is used. Bottles thus charged with brine and bound together were broken side by side with the Harden grenades and found to be equally valuable.
It thus appears from the experiment that any person can construct as good and effective grenades as those offered in the market at $7 and $10 per dozen. Bottles filled with brine and placed around the premises will afford considerable protection, especially when used upon the flames when the fire just begins. Salt solutions have the further advantage of not being easily frozen--never enough to burst the bottles.
The Lewis hand fire-extinguisher was next investigated. This consists of a tin tube about two feet long containing thirty-four fluid ounces of soda in weak caustic ammonia. From the trials made we could not notice any appreciable superiority over the salt solution as used in the Harden grenade. It has the disadvantage of not being made to break by being thrown, but must be opened by having a cork extracted from one end of the tube, requiring a smart jerk. The solution is then sprinkled on the fire by the operator.
We herewith append a number of fire-extinguishing compounds, all of which are highly recommended by various authorities:
Common salt 43 per cent. Alum 19.5 per cent. Glauber’s salt 5.1 per cent. Soda 3.5 per cent. Water glass 6.6 per cent. Water 22.3 per cent.
=Richardson’s Fire-Extinguishing Powder.=
Alum 4-1/2 pounds. Common salt 10 pounds. Glauber’s salt 1 pound. Soda 1 pound. Water glass 1-1/2 pounds.
Green vitriol 4 parts. Ammonium sulphate 16 parts. Water 100 parts.
Carbonate of soda 8 pounds. Alum 4 pounds. Borax 3 pounds. Carbonate of potash 1 pound. Silicate of soda solution 24 pounds.
Mix thoroughly and add 1-1/2 pounds of this mixture to each gallon of water, when required.