Show grains of sand land the manufacture of sand is ia an important industry which has pittsburg for it its headquarters although tho the sand is not made within tho the limits of the city there ifft is a considerable traffic in monongahela adiela sand which is scooped up from the bed of the river to be used for common building purposes but the manufacture of sand is quite another affair and the product goes into quite a different commodity which is glass practically glass is almost pure sand other substances used in its manufacture for fluxing flexing being consumed while the sand is transformed to a greater or less lesa degree t transparency used in glass makin mak making in is almost pure silica s so 0 nearly puro pure tha that there is ia less than I 1 per cent of iron magnesia and aluminum to per cent of the other and of this sand which is quarried out of the his hills and ground down to various degrees of fineness and washed to various degrees of whiteness tons are manufactured fractured daily tons being consumed in in and about pittsburg and tons going into eastern ohio and west virginia to wheeling bellaire columbus and all points within a cire circuit alt of miles from pittsburg popular science monthly |