After a violent easterly storm in the night, which clears up at noon, I noticvce that the surface of the railroad causeway, composed of gravel, is singularly marked, as if stratified like some slate rocks, on their edges, so that I can tell within a small fraction of a degree from what quarter the rain came. These lines, as it were of stratification, are perfectly parallel, and straight as a ruler, diagonally across the flat surface of the causeway for its whole length. Behind each little pebble, as a protecting boulder, an eight or a tenth of an inch in diameter, extends northwest a ridge of sand an inch or more, which it has protected from being washed away, while the heavy drops driven almost horizontally have washed out a furrow on each side, and on all sides are these ridges, half an inch apart and perfectly parallel.
All this is perfectly distinct to an observant eye, and yet could easily pass unnoticed by most. Thus each wind is self-registering.
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