Show Increase se In Grinding Materials The value of abrasive materials materials' produced prO In the United States In 1910 1316 was according to statistics compiled com corn piled by P. P F. F J. J Katz of ot the United States geological survey department of the Interior Of Ot this was waa the value of natural abrasive materials materials mate mate- rials and J the value of art arti- arti artificial abrasives The abrasive materials materials mate mate- rials imported for consumption In 1916 were valued at The apparent apparent ent total consumption of abrasive materials ma ma- tennis In 1917 was thus which was was was' an Increase ase of nearly 30 pet cent over 1915 I |