Popular Science Monthly 



111 



destruction of the tire hastened. 

 Injuries to the wheel and tires are 

 by no means warranted by the 

 sHght advantage gained in point of 

 convenience to passengers. 



Rim Cutting 



Fifteen, even ten years ago, tht 

 beads of rims could cut a soft tire. 

 Nowadays, rims are so ingenious- 

 ly designed that only a bat- 

 tered section will force itself 

 into the tire. The hooks of a 

 clincher tire may chafe a soft 

 tire because the hooks of the 

 side rings cur\'e in to grasp the 

 bead. Under-inflation is there- 

 fore to be avoided. That ap- 

 plies to all tires regardless of 

 type. A blow will bend a rim 

 flange and form a projection 

 which only too easily digs its 

 way into the tire. Since rims 

 are made of steel they rust. 

 Rubber and rust are enemies. 

 A little rubbing with emery 

 paper and a little 

 preservative 

 coating will save 

 many an expen- 

 sive tire. 



Because side walls must be 

 thin they are vulnerable. 

 For that reason car tracks 

 should be avoided. The rails 

 cut through the rubber at the 

 edges of the tread. Cobble- 

 stones never provided an 

 ideal automobile pavement; 

 but a quarter of a mile of 

 cobble is preferable to a 

 gouged tire. 



Anti-Skid Devices 



Anti-skid chains and 

 silnilar devices are often 

 fj a necessity. Apply them 

 k tightly and forget to re- 

 I move them, and the tire 

 will show the result in 

 deep cuts. Rubber 

 yields; metal does not. 

 A dull knife will pass 

 through cheese; and a 

 dull chain will cut a tire. 

 Besides, any extra weigh t 

 A sudden applica- ^^"^ additional heat, 

 tion of the brakes and rubber is very 

 produced this sensitive to heat- 



Above: How a 

 tire is dented 

 when running 

 over a sharp 

 stone. Just as 

 when you break 

 a stick across 

 your knee, the 

 fibers farthest 

 from the jjoint 

 of contact are 

 the first to give 



On the inside of 

 a tire, large 

 break in the 

 fabric. This re- 

 sulted from an 

 accident, the 

 wheel passing 

 over a stone. 



Not the slightest mark or indentation on 

 the outside of the case was left ( note X in 

 section showing outside). The effect is just 

 the same as if the tire had received a series 

 of hard blows from a big sledge hammer 



The rubber of a tire suffers chemical de- 

 terioration from oil, gasoline or acids. 

 Drop any of these liquids upon a tire and 

 it is just as if you had dropped vitriol upon 

 wood or iron. Wip)e away the gasoline 

 or the oil which may have been accidentally 

 spilled upon a tire, and never allow the 

 wheels to stand in puddles of oil on a 

 garage floor or a roadway. 



Light has a strong and harmful chemical 

 action upon rubber. 



