An Automatic Vehicle Brake

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The brake shown in the illustration applied to the running gear of a wagon is automatically removed from the wheels when the vehicle is moving foward, the brake being applied when the vehicle is backed or is standing at rest. The improvement has heen patented by Henry N. Davis, of Dow City, Iowa. The shaft carrying the brake shoes is journaled in bearings on the rear hounds, shown in transverse section in the small figure, and centrally on the shaft is a gear wheel meshing with a pinion journaled in bearings on the under face of the hounds, the latter shaft having a handle for use when desired, and having also a central arched portion connected by a spring with the rear axle. The tension of the spring normaHy turns the shaft to cause the pinion to act on the gear on the brake shaft to apply the hr lkes. which are taken off when the vehicle is started by the counteracting tension of a chain carried forward over suitable guide-ways to attachment to a clevis pivotally connected with the doubletree, the bracket or ('Iel' is being secured to a block sliding in the tongue of the vehicle or on the forward end of the reach. When the horses draw forward, causing a limited forward movement of the chain, the pinion and gear are rotated to remove the hrake shoes from the wheels. Suicidal Wasp. M. Henry, a Frenshman, being curious to see the effect of benzine on a wasp, put some of it under a gla8s in which a wasp was imprisoned. The wasp immediately showed signs of great annoyance and anger, darting at a piece of paper which had introduced the benzine into his cell. By and by he seems to have given up the unequal contest in despair, for he lay down on his back, and bending up his abdomen, planted his sting thrice into his body, and then died. M. Henry allowed his scientific interest to overcome his humanity so far as to repeat the experiment with three wasps, only to find that the other two did likewise. He is, therefore, of opinion that wasps, under desperate circumstances. commit suicide.

Scientific American Magazine Vol 73 Issue 25This article was published with the title “An Automatic Vehicle Brake” in Scientific American Magazine Vol. 73 No. 25 (), p. 390
doi:10.1038/scientificamerican12211895-390

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