Page:Popular Science Monthly Volume 90.djvu/776

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� � � ��Two steel cables anchored to trees on oppo- site banks form the only support of this bridge which spans a river fifty feet wide

How Springville Built a Bridge of Cables, Boards and Chicken Wire

WHEN the State refused to help them by providing a bridge across the Tula River near Springville, California, the resi- dents decided to erect their own bridge, the one shown above.

The bridge spans fifty feet of river. It is suspended by two half-inch steel cables which are anchored to trees on the opposite banks. Strong pine planks are placed across the tops of these cables. Steel wiring and bolted steel clamps hold the planks securely in place. Between the planks, wooden boards are nailed to form a board-walk.

When the bridge was first used, nerv- ous persons refused to walk across it be- cause of its narrow- ness. Two light steel wires were then placed not three feet above the level of the foot-bridge. Ordinary chicken-coop netting was suspended from these to the sides of the bridge as railings.

��Fabric Linings Take the Place of Wood and Steel in Braking Trains

IT is a surprising fact that ordinary fabric is such a superior friction material that it is replacing all other substances for braking trains. Cotton or asbestos brake-linings are better than wood because they can stand intense heat much better. More- over, fabric linings can grip wet wheels more strongly than wooden brake-blocks can. The reason that iron blocks have given way to fabric linings is interesting. It has been proved that in the New York sub- way, three quarters of a ton of iron dust is scraped from the train wheels by the metal blocks each month for every mile of traveling. This dust not only short cir- cuits the electrical signaling apparatus and interferes with the dispatching of the trains, but by mixing with the oil thrown from the train motors it produces a highly in- flammable compound. The great danger from such accumulations is entirely done away with when fabric brake-linings are used.

���All the material used in the construction of this house was taken from rubbish heaps after the great fire. Bits of crockery decorate it

��A House That Arose Out of the Ashes of Chicago's Great Fire

THERE are houses of brick and stone, houses of grass and even houses of glass, we are told, but perhaps the oddest of all as to history is the Relic House in Chicago, 111., which is built entirely of debris gathered after the great fire of 1871. The house has been standing for forty-five years and serves not only as a reminder of the great disaster but as a restaurant and lunchroom as well.

The usage to which this structure is put testifies to its attractiveness. In fact it was never in- tended to look other- wise than attractive, in spite of its origin. Old horseshoes, scraps of metal of every kind, and nails were melted down. Bits of broken crock- ery were employed as decorative material. All the wood neces- sary for the structure was easily obtainable from rubbish heaps. It is one story high.

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