"GLADSMUIR, a parish, containing the post-office villages of Gladsmuir, Longniddry, and Samuelston, also the village of Penston, in Haddingtonshire. It is bounded by the frith of Forth, and by the parishes of Aberlady, Haddington, Salton, Pencaitland, and Tranent. Its length southward is fully five miles; its breadth is 4 miles; and its area is about 10 square miles ... The village of Gladsmuir, or Kirktown, stands on the eastern verge of the parish, on the highest point of the ridge between Tranent and Haddington, 4 miles west by south of the latter. The culmination of the ground here, about 350 feet above sea-level, commands a superb panoramic view of the Forth, Fifeshire, and the Lothians, and is remarkable for thunder storms, one of which in 1789, burst upon the schoolhouse, and killed two of the children ... Population in 1831, 1,658; in 1861, 1,945." [From the Imperial Gazetteer of Scotland, edited by John Marius Wilson, 1868]
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