Page:Popular Science Monthly Volume 89.djvu/686

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��Popular Science Monthly

��Search for Durable Roads in a St. Louis Park

TO the average motorist there are only two kinds of roads, good roads and bad roads. To the road engineer, roads are divisible according

��Charging the Weak Magnetos of Automobiles

��THli magneto on yi elifectiveh' reiuvcnt

���From the dial which the engineer is examining the durability of the roadway is determined

to materials, such as asphalt, brick, etc.

An interesting case came to light recently when the road engineers of St. Louis began discussing stresses, temperature coefficients and other highly technical things in connection with the roadbed of a St. Louis Park. Then an effort was made to find a pavement which would maintain its smoothness regardless of weight and speed of \chicles. The roadway was divided into small sections and concrete ap- plied in \'arious mixtures. Then the roadbed was tried out. The motorist looked upon it as an excellent stretch for a spurt; the engineer looked upon it with an instrument almost as delicate as a microscope

In the photograpl by the engi- n e e r s is shown with a solid bar of steel laid parallel to it for pur- poses of accuracy in | measure- ment.

���RcjuvcnatinK your Ford magneto is the work of five minutes with this new specially dcsinncd charger

��our Ford can be rejuvenated by means of a magnet-charger specialK- designed for use where a iio-\()lt direct current line is not a\ailal)le. When \our car fails to start easily and \ou have to change from high to low speed frequentK-, you may be sure the magneto has become weak. When someone tells you that he cannot hear your voice in the telephone, it is because the receiver magnet is weak. Part\' lines are especialK" liable to suffer from weak generator mag- nets.

The magnet -charger can be

operated from an ordinary six-

\Lilt storage-battery, or from a

storage-battery charging outfit.

such as that used in garages to charge

starting or lighting batteries. Three or

four applications of the current on each

end of the magnet up to its maximiun

strength may be made.

The charger is in the form of a small box ha\'ing a handle and also a hole in which one end of the magnet is placed. The two ends are placed on a piece of iron which closes the circuit. The magnet-charger is raised to the cur\ed part of the magnet three or four limes, each lime closing and opening the switch. The _ charger is then held over the top of the magnet, and the same operation isrejieated with the s w itch open . T h e m.ignel is now fiilh- charged. The sim- plicity of the oiK-ration is its chief recommen- d.ition.


��Maybe you have special needs. Write to the editor about anything within the scope of the magazine. He will be glad to help you.

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