The book Arran; - Cook Clan

124 THE BOOK OF ARRAN
There is also clay ironstone of good quality at Corrie and
on the Cock shore, and the Corrie stuff seems formerly to
have been exported.^
The ore was smelted in a shallow hole or pot in the ground,
usually, as in mainland examples, from six to seven feet in
diameter. The bottom had a hearth of clay which would be
extended with flat stones, and the sides seem also to have
been cobbled. At Kilpatrick, Shisken, the furnace is a hollow
nine to ten feet in diameter on the top of a mound, and is
rudely built round. Charcoal was the heating material, and
was heaped upon the ore till sufficient heat was got to reduce
the mass, and the slag began to flow. The pure metal was
picked out, probably beaten and re-heated and worked at
till in a fit state for use. Meantime almost as much good
metal was lost in the slag, mounds of which of the older black
kind, still rich in ore, are found near the old furnaces—in one
case a mass which must weigh close on a hundred tons. At
Kilpatrick the slag has been thrown down the slope ; from
Cnoc Dubh, between Brodick and Lamlash, it has been removed
for roadmaking. At Largie Beag, by the road from
Whiting Bay, ten carts of slag were taken for use in making
drains. These open furnaces are known as ' bloomeries,' ^
and the first part of the word is still used for a mass of iron.
Nothing is gained by tabulating all the sites of bloomeries
in Arran ; an indication of their general character suffices,
for one is own brother to the next. They are on hillsides
or a good bit inland, for they had to be where the wood was ;
near a stream, for water was much used both in damping
the charcoal so as to maintain a steady heat and in cooling
the slag. At Coille Mhor, Loch Ranza,^ the slag lies at a
spot 100 feet above sea-level, while in a flat below are the
' Memoir (21) Geological Survey, p. 147.
2 Old Knglish htoma, u lump or mass, with the suffix -ery.
3 ' A knoll to the south-east of this heap of slag is known as the "hammer-head,"
and the second as the "smith's hill."'—Macadam, 'Notes on the Ancient Iron
Industry of Scotland,' Proc. Soc. Antiq. Scotland, vol. xxi. p. 98.