Page:Popular Science Monthly Volume 88.djvu/252

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��Popular Science Monthly

���When these txees were young, fence boards were tninks. The boards are now completely buried

A Tree Captures a Fence

MANY years ago a row of Irish poplar trees was used for the posts of a fence, and boards were nailed to the trees. The trunks of the trees, in the process of growing, gradually over- lapped the boards, until now the boards are near the center of the trunks. Not needing the fence any longer, the owner sawed off the boards, the remnants of which still protrude from the trunks of the trees.

To Keep Automobiles off Railroad Tracks

THE new long distance railroad signal has been brought about by the new conditions arising from the general use of the automobile. Chauf- feurs are so frequently found driving through country which is new to them that they often find themselves on the tracks of a railroad line before they know it. The long distance signal was designed to give them sufficient warning of the proximity of the rail- road tracks to enable them to be on the alert and to avoid accidents on the tracks. The new signal was designed by the officials of the Southern Pacific Railroad, and the first one w^as placed at the crossing of the main street in Tropieo, Cal., but such excellent re- sults attended the experimental instal- lation that others are now being in- stalled. The use of the new signal will be further extended.

��The lines of the sig- nal are such a departure from the typical rail- road signal that it can- not help being observed by the wayfarer, either mounted or afoot. It consists of a tube of metal eight inches in di- ameter and two and a half feet long, mounted on a support, which, in this case is a piece of three-inch pipe. The pipe also offers accom- modation for the elec- tric wires which supply the current. The tube- is painted black and is mounted in the direction of the road, so that the red light inside may be seen at

a great distance

before reach-

i ng the

sisrnal.

��nailed to their in the tree

���A red light inside the tube of this railway signal is visible for a great distance, and the disk attracts attention in the daytime

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