Note 389 — Chapter I · (continued 2)

Appendix xix. of the Report of the United States Coast Survey for 1880 (Washington, 1882) is a paper by Charles A. Schott of “Inquiry into the Variation of the Compass off the Bahama Islands, at the time of the Landfall of Columbus in 1492,” which is accompanied by a chart, showing by comparison the lines of non-variation respectively in 1492, 1600, 1700, 1800, and 1880, as far as they can be made out from available data. In this chart the line of 1492 runs through the Azores,—bending east as it proceeds northerly, and west in its southerly extension. The no-variation line in 1882 leaves the South American coast between the mouths of the Amazon and the Orinoco, and strikes the Carolina coast not far from Charleston. The Azores to-day are in the curve of 25° W. variation, which line leaves the west coast of Ireland, and after running through the Azores sweeps away to the St. Lawrence Gulf.