Ohio: truck tire being pulled out of vulcanizing mold, in Mansfield Ohio. Research department at Pennsylvania tire company tests tires containing no natural rubber(substance called Butyl). Man writing down read outs from battery of tests, as tires have pressure exerted on them and weight added. Also pierced by presses. Tires tested at Detroit Arsenal Test Operation Ground (near San Antonio, Texas). Army jeep tests the tires in rugged terrain.