Show Blacker Than ban Coal To most of us u. coal seems eem to b bt b. s the limit of blackness but there is I. isone i ione s one substance that II is much blacker silica black It Is formed of ot coal 1 crushed to a fine powder and mixed d with pulverized silica This compound com corn pound is heated in a vacuum a aa at ata a B temperature of ot COO degrees degree Fahrenheit FahrenheIt Fah Fah- and when the gas gar and other oth other er products have been driven off th the e residue is found to be much blacker r than coal says say a writer in fa London Londo n Tit Bits Magazine Silica black ha has haa s many y uses uses paints paints shoe polishes Insecticides and fume tume absorbents absorbent r usually contain a certain tion of it t. t Its value lies largely Inthe in inthe n the fact that it t mixes mixes' easily wl with oil cU the color is permanent and It I t resists acids and chemical |