186 
JOURNAL OF THE PLYMOUTH INSTITUTION. 
improvement is the substitution for hand labour in puddling. The 
principal supplies of ore are derived from the coal measures — argil- 
laceous ores and black band. Lesser supplies are derived from the; 
lias and oolite. The mountain limestone produces red and brown 
hematites ; and the Devonian rocks afford brown hematite and 
white carbonate. 
A lode containing magnetic ore has recently been discovered at 
Monksmoor Farm, near TJgborough Beacon. 
THE PEE-HISTOEIC REMAINS OE BRITTANY. 
ABSTRACT OF CAPTAIN OLIVEr's PAPER. 
(Read March 28th, 1871.) 
The lecture was an exhaustive statement of the conditions under 
which the megalithic remains of Brittany occur, and of their re- 
lationship to the allied monuments in other parts of the world — 
specially the West of England — with an examination of the many 
theories which have been started concerning them, down to the 
very latest, those of Mr. Ferguson. Captain Oliver endorsed the 
view that the ancient seat of the builders of the dolmens (the vary- 
ing kinds of which he fully and clearly described) was in Central 
Asia, and that they were a conservative and exclusive race, who, 
resisting absorption by a superior people, were expelled from their 
aboriginal homes westward — one branch passing along the northern 
shore of the Mediterranean, and the other towards the coasts of the 
Baltic. From Scandinavia they reached the British Isles and 
Brittany, passing on through Spain and Portugal into Africa, the 
dolmens of which are the most recent known, as those of the 
Crimea are the most ancient. More generally known than the 
dolmen mounds of Brittany are the stone avenues and circles of 
upright stones found at Carnac and other places in the department 
of the Morbihan. These remains Captain Oliver had visited and 
surveyed in company with Sir H. Dryden and the Rev. W. Lukis. 
He considered them and the similar but smaller megalithic struc- 
tures of Dartmoor and other parts of this country to be of a sepul- 
chral origin. All cromlechs, dolmens, kists, and other sepulchral 
stone chambers he held to have been originally covered with 
tumuli. Some of these latter had their basements strengthened by 
