Popular Science Monthly 

 It Has Both a Pneumatic and a Solid 

 Tire— This New Truck Wheel 



681 



DOZENS of inventors have patented 

 wheels which are intended to have all 

 the buoyancy of the pneumatic tire and 

 which are blowout- and puncture-proof. 

 The problem is difficult 



to solve for the ordinary j^- ' ,^_ ^Axle spindle 

 pleasure vehicle, but still 

 more so for the motor- 

 truck. As a result, 

 nearly all motor-trucks 

 are equipped with the 



ing come into contact with the wide upper 

 edges of the casing that hold the tube. 

 The side thrust of the wheel when in 

 motion is taken up by means of small 

 thrust bearings between the inner and 

 outer wheel parts as shown. 



Driving 



chain 



sprocke 



Rubber burner 



solid type of tires 



A new motor- 

 truck tire has been 

 invented in which 

 both the solid tire 

 and the pneumatic 

 principle are ingen- 

 iously combined. 

 The drive is trans- 

 mitted directly to the 

 rim instead of to the 

 hub section. This re- 

 lieves the pneumatic 

 part of the wheel from 

 the driving strains. 



The wheel consists of 

 two main parts, a hub 

 carried on ball-bearings, 

 with a U-shaped steel 

 casing embracing a rub- 

 ber air tube, and an outer part driven by 

 the regular chain and sprocket and carrying 

 the dual tires, as shown. 



The outer part has a convex-shaped cas- 

 ing which encircles the pneumatic tube and 

 comes into contact with it, thus providing a 

 narrow track upon which the tire rolls when 

 the wheel revolves. By this means the 

 cushioning effect of the pneumatic tire is 

 retained, with 

 none of its disad- 

 vantages such as 

 punctures or 

 blowouts. 



Should the 

 pneumatic 

 tube become 

 deflated for 

 any reason, 

 the truck may 

 still run with- 

 out damaging 

 the wheel because two 

 rings of rubber on each 

 end of the contact cas- 



Ball bearings 



Rubber tube 



Ball bearing to 

 take side thrust 



Contact casing 



Dual truck tires 



The drive is transmitted directly to the 

 rim instead of to the hub section. This 

 relieves the pneumatic part of the 

 wheel from the heavy driving strain 



Why Do Salmon Go 

 Annually Out to Sea? 



THE rocks of the 

 earth are having 

 their sodium con- 

 tents washed out 

 continually, there- 

 fore the rivers of 

 today have less salt 

 than the streams of 

 former years. This 

 is the reason ad- 

 vanced for the regu- 

 lar trips which 

 schools of salmon make 

 every year to the deep 

 sea. The river having 

 become too fresh for it, 

 the salmon must needs 

 go out to the ocean for 

 the saltness necessary 

 for its best develop- 

 ment and comfort. 



Salmon are content in 

 the rivers all the sum- 

 mer and fall, during which time they spawn. 

 The young make their first trip to the sea 

 when they are about one year old. 



You Can't Spill Ink When Pouring 

 From This Bottle 



AN ink bottle which works somewhat 

 .11. on the principle of the non-refillable 

 bottle, and which prevents waste and 

 smearing of the hands, has been invented 

 by Frank H. Silverthorne, of New York 

 city. There is a small ball in the neck 

 portion of the bottle 

 so that the flowing 

 ink can be cut off 

 in an instant. As a 

 further precaution a 

 seal is provided in- 

 stead of a cork. With 

 the seal in position 

 the bottle will stand 

 any amount of shak- 

 ing without leaking. 



The slightest movement of 

 the hand will cause the ball to 

 cut off the flow of the ink 



