Page:Popular Science Monthly Volume 90.djvu/930

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914

��Popular Science Monthly

���At left above: Rescuing a drowning person with the new boat ladder. One man is sufficient to effect the rescue. At right: The boat ladder telescoped out and ready to be carried overboard

��Saving a Drowning Person with an Ingenious Boat Ladder

THIS boat ladder, which makes it pos- sible to rescue a drowning person and pull him in the boat without capsizing it, is floated overboard and is attached to the boat by a rope. The man overboard is pulled near to the ladder and placed upon it backward. Then the ladder with its load is pulled into the boat.

��Tlie Double Automobile Spring. If One Breaks, the Other Conies into Action

AN automobile is as comfortable and as l\ serviceable as its springs. Should they break, further progress is impossible unless emergency repairs are made. The value of an arrangement which would make such an accident well-nigh impossible is therefore apparent. Clabeorn P. [Ran- dolph, of Los Angeles, California, has designed a duplex spring which brings an auxiliary spring into action on the failing of a main spring; it also reinforces a main spring whenever it is overloaded.

It has extra horizontal leaves which project out at the top and bottom of the main spring. These are kept apart by a connecting-rod so that, when the main spring is loaded normally, the auxiliary leaves are kept out of action. The moment the load on the main spring is made greater than normal, however, the extra compres- sion on the main spring will press the auxiliary leaves nearer together, and bring

��them immediately into action. A weaken- ing or breaking of the main spring would bring about the same result. As soon as the main spring begins to "give," the leaves are again brought nearer together.

A device of this kind could easily be made to absorb any overstrains on an automobile spring when traveling over rough roads. The connecting rod need only be dis- connected from the upper leaves and screwed down into the lower ones so that they are not too far apart. Stresses from the excessive recoils from the roads will then be taken up by the auxiliary spring as well as by the other.

���Under normal loads, the horizontal leaves of the auxiliary spring fit loosely above and below the main spring

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