Page:Popular Science Monthly Volume 91.djvu/697

 Popular Science Monthly It Has Both a Pneumatic and a Solid Tire— This New Truck Wheel

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��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

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