191 
Il.—On the Detrital Tin-Ore of Cornwall—By Wiuu1am Jory 
Henwoop, F.R.S., F.G.S., Sometime Her Majesty's Assay- 
Master of Tin in the Duchy of Cornwall, Member of the 
Institution. 
Read at the Spring Meeting, 16th May, 1873. 
AP the detrital deposits-of tin-ore in Cornwall and Devon have 
been wrought from remote antiquity, they are nearly—though 
not yet quite—exhausted. The most important* have often, and 
other of themt have sometimes, been described; on some few, 
* The rich and extensive deposit at Carnon has been described by 
Maton, Observations on the Western Counties, ii, p. 173. Rashleigh, British 
Minerals, i, p.5. Berger, Geol: Trans :i, p. 162. De Luc, Geological Travels, 
ili, p. 325. Smith, /bid, iv, p. 409. Hitchins and Drew, History of Cornwali, 
li, p. 264. Sedgwick, Annals of Philosophy, ix, p. 249. Dufrénoy, De 
Beaumont, Coste, et Perdonnet, Voyage Métallurgique en Angleterre, ii, p. 
261. Henwood, Cornwall Geol: Trans: iv, p. 57, v, p. 91.* The large 
and productive formation at Pentuan has been illustrated by Bonnard, Journal 
des Mines, xiv, p. 450. De Luc, Geological Travels, iii, p. 3838. Smith, Geol: 
Trans: iv, p. 404. Hitchins and Drew, History of Cornwall, ii, p. 62. 
Héron de Villefosse, Richesse Minérale, ii, p. 354, Pl. xxi, Fig.7. Sedgwick, 
Annals of Philosophy, ix, p. 247. Dufrénoy, De Beaumont, Coste, et Per- 
donnet, Voyage Meétallurgique en Angleterre, ii, p. 258. Colenso, Cornwall 
Geol: Trans: iv, p. 29, Pl.i. Winn, Reports of the Royal Institution of 
Cornwall, xxi, (1839), p. 45; xxii, (1840), p. 38. Combe’s, L’Hxploitation des 
Mines, i, p. 352, Pl. xiii, Fig. 3. Stocker, Transactions of the Penzance 
Natural History Society, ii, p. 88. Von Cotta, Ore-Deposits, p. 421. Flower, 
Annals and Magazine of Natural History, 4th Series, ix, p. 440. 
{¢ Smaller accumulations of similar character, worked at Dowyran, 
Pillianeth, Pemedar, Leswhidden, Bostraze, Drift, Numphra, Kerris, Chy- 
venhall, Clija, and Marazion-marsh, in the western—at Porthleaven, Loe- 
pool, Porkellis, Portreath, Porth Towan, and Perran-porth, in the central ;—at 
Tregony, Pensagillis, Hallibesack, Frog-moor, Swan-pool (Ladock), Treloy, 
Goss-moor, Gaverigan, Poth (Porth), Par, Sandrycock, Tregurthy-moor, 
Merry-meeting, Mullinis, Grove, Levrean, Water-gate, Pendelow, Broad- 
water, and Bodgara-moors, in the eastern part of Cornwall; and at Lydford, 
Walkhampton, Sheepstor, Manadon, Chagford, Kingsteignton, and Teign- 
grace, in Devonshire; have been described—by Borlase, Natural History, 
(second edition), p. 162. Pryce, Mineralogia Cornubiensis, p. 68. Jars, 
B3 
