Page:Popular Science Monthly Volume 89.djvu/702

 fi8<S

��VnpiiUir Science Montlih/

��Recording

���The paint is first vaporized and then forced thniu^li h-^^ and sprayed on the cars by means of compressed an

��the Vibrations of a Motor- Truck Spring THE novel device illustra- te<l was recently designed to enable a truck manufactur- ing company U) judge what springs are best adapted for its vehicles.

The device consists of a hollow drum mounttxl on a ^■ertical axis and carried in an oix-n-siiied box attached to the truck body at the rear of the driver's cab. It is re- volved by gearing from the front wheels of the truck through a flexible cable. A blank strip of paper is fed around the outer circumference of

��I

��The Hose Is Mightier and Quicker

Than the Brush F KIPLING had only waited long

enough before saying it our picture might have given him his idea abcut painting with a comet's tail for a brush and the sky for a canvas. However, the painters shown in the accompanying illustration are not artists and their canvas is not the sky but two brand-new steel box-cars which ha\e just emerged from the shop

This is the fastest and most economical method of painti yet devised. Th paint is first vn- ])orized and then forced throutili the hose and sprayed on the cars by com- pressed air.

While the ' photographer was adjusting his camera for a snapshot the ends of both these cars were painted, which gives an idea of how rapidly t h e work is ac<(inii)li-'hcd.

��\ H9 1 iPfJMG UXVDE D

��N92 SPRING lOAOeO

���Inscription of a record on the strip of paper around the drum

��The device is carried in an open-sided frame attached to the body of the truck at the back of the driver's cab

��the drum from a roll beside it. While the truck is run- ning the spring \i brat ion is proportional to ilu' motion be- t w c e n t h e body, to which the device is fixed, and the axle. This record is in- scribed on the sheet around the drum by m e a n s of a pencil carried on a .swivel by a spring-arm.

�� �