John Cordeaux,
Report on the Migration of Birds in the Spring and Autumn of 1880…
“ At our more northern stations the lighthouses for the most part stand at great elevations, and it is worthy of note that from such stations as the Bell Rock, Pentland Skerries, and Whalsey Skerries, on the east coast, and Dhuheartach and Skerryvore, on the west coast, &c., we have the best filled schedules, showing that stations upon lower and isolated elevations are the best points of observation. ”
