20 DECEMBER 1919, Page 12

COAL ECONOMY.

[To THE EDITOR OF THE " SPECTATOR."'

Sra,—Every one knows that a shovelful of coal-dust will often prevent a coal or coke fire from burning properly, mainly by hindering the draught. Possibly it may not be so generally known that if the coal-dust be put into a paper bag it forms a lump when the paper bag is burnt, and then burns as well as a lump of coal without damping down the fire. Knowledge of this fact may prevent much waste.—I am, Sir, &c.,