Show TESTS SHOW WHY TIRES suii I 1 LAST S ans AT bureau of standards uses machines to determine facts on rubber tile the following conclusions hive have been reached rei cheu as ag to factors velh ahia influence the life of tires according to it paper which has just been issued by tile the bu reau of standards department of neice 1 A carcass in which tile tho friction rubber Is slightly compounded appears to stand up better belter under test than limn one in which pure guru Is used 2 within tho the customary limits of nil ill pressure pies suro usei used in tires the higher tile pressure the lie bettor better tile tire will au stand up U B fabric tiros tires develop it a iauch higher temperature than cord tires tiles und their life la IN much less thull cord tires separation causes failure 4 separation which was the prin elbal of failure it lu these tests lid did not always take place in tile the sumo locution location in ili the tire it occurred in inest cases between the tread and broaster bro tirva alter ker breaker eilker br unit und cush loti cushion laid and carcass or between tile outer two piles 5 any particular brand of tire usually showed a characteristic typo of fall ino c 0 some inalea hes of tires blow out Il liell sooner after i litt leiis A sturt vI alinn 7 inner tubes tor for truck tires tins appear to withstand the action of heat better than those of tile the guill type some improvement noted it Is intel t to note lioto that of tin tile tested in general I 1 not lot than one half tile sal liples passed tile hie test requirements though a gellel al II 11 ani wits was noted luring the po lie aloi covered by tile tests tit in tit alie cast case of boulo alre tho the publication briefly tin the testing level 01 p d I 1 li I 1 y t he I 1 bu u if call nil for this ids work fly 1 using machines ll it la IS possible to determine in 18 48 hours facts which would other wl wise rpaul re several months use on oil tile tho rond load A table gives tile lie results of the I 1 acht e s Is tills Is cnown ns as 1 gic inper no as and ma alay it in abt obtained 1 I 1 t LI from the sill erl it leaden t of documents government printing ton D C tit nt 10 cents pol pei volly opi |