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Field-book for railroad engineers. Containing formulas for laying out curves, determining frog angles, levelling, calculating earth-work, etc., etc., together with tables of radii, ordinates deflections, long chords, magnetic variation, logarithms ...
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Compass Variation and Deviation - how to calculate them - Building The Best Powerboat Company In Britain
IV. On the variations of the diurnal range of the magnetic declination as recorded at the Prague observatory
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