178 SECTIONS OF LEAD MINES IN THE GRAVEL AT CLWYDD. 
where lead is found under such circumstances in sufficient quantity 
to be worth working. It is locally called flat ore, from its occurring 
in flat or horizontal beds of gravel. Its occurrence here is explained 
by the position of this gravel bed at the mouth of a valley of de¬ 
nudation, cut in the limestone hills of Halkin, which are full of lead 
veins. The gravel resulting from this destruction contains fragments 
of lead ore, mixed up with the wreck of the rock, that formed its 
matrix before the excavation of the valley. Its thickness is unusually 
great, and several mines are worked in it; one, called Gronant Mine, 
gives the following section: 
1. Vegetable mould, two feet. 
2. Clay, mixed with some sand and rolled stones, 26 yards. 
3 . Gravel beds, containing rolled pieces of lead of all sizes, eight 
yards. 
In another mine, called Tal-ar-goch, the remains of ox and stag are 
found at present: and in 1815 a pair of stag’s horns were discovered 
at 60 yards below the surface, and are now in the possession of the 
Earl of Plymouth at Tardebig. The section of this mine is : 
1. Vegetable mould, two feet. 
2 . Clay, 26 yards. 
8. Sand and gravel, 68 yards; containing pebbles of copper as 
well as of lead. Horns, teeth, and bones, are found in it, 
at from 40 to 70 yards from the surface, and also at the 
bottom of the gravel, in immediate contact with the subjacent 
limestone rock. 
Another shaft dug one mile south of St. Asaph, at a spot between 
the Ebwy and the Clwydd, presented irregular alternations of clay 
