In mining law. The line of declination of strata; the angle which measures the deviation of a mineralized vein or lode from the vertical plane; the slope or slant of a vein, away from the perpendicular, as It goes downward into the earth; distinguished from the “strike” of the vein, which is its extension in the horizontal plane, or its lengthwise trend or course with reference to the points of the compass. King v. Mining Co., 9 Mont. 643, 24 Pac. 200; Duggan v. Davey, 4 Dak. 110, 26 N. W. 887.
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