Geology
The soil is principally a rich loam, varying from 10 to 16 inches (410 mm) in depth, and resting on a hard and compact substratum of floetz limestone. The water table is unusually high. The low group of nearby hills, which includes Lyons and Oughterard in Co Kildare and Windmill Hill, Athgoe, and Rusty Hill in Co Dublin, are composed of clay-slate, grauwacke, grauwaeke-slate, and granite. The grauwacke consists of small and finely rounded and angular grains of quartz, numerous minute scales of mica, small fragments of clay-slate, and sometimes portions of felspar. The grauwacke consists of small and finely rounded and angular grains of quartz, numerous minute scales of mica, small fragments of clay-slate, and sometimes portions of felspar and red sandstone.
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