230 ON THE DETRITAL TIN-ORE OF CORNWALL. 
At Lark-holes* near Redgate tin-ore is scattered in isolated 
masses, and at Gonamenat on the south-western slope of Caradon 
as well as at Kit Hill,t it is disseminated, through the granite. 
Notwithstanding every part of the waste between Powne’s- 
cost and Five-lanes has been furrowed in search of stream-tin-ore, 
the miner has found no encouragement there or in the neighbour- 
hood§ ;_ for, at present the entire tract and the (Drains and the 
Saint Neot) tributaries of the Fowey—which rise in it—scarcely 
afford a livelihood to thirty workmen. 
At Netherton, in Saint Neot, operations have been lately 
resumed on a—previously wrought yet unexhausted—spot, beside 
the Drains river. The present works have not yet reached the 
sides of the ancient opening; and the vegetable mould, the more 
recent granitic sand and gravel, the peat, and the small angular, — 
subangular, and rounded masses of granite, as well as the ingredi- 
ents associated with them, were all indiscriminately mixed by the 
earlier workmen; neither the works nor the matter extracted 
from them affords, therefore, available clue to the natural succes- 
sion of the several deposits. The small quantity of in-ground 
still remaining is covered by large blocks|| of hard granite ; and it 
cannot be extracted until they have been removed. The Shelf— 
everywhere more or less disintegrated—consists of rather coarse- 
grained granite; in which eroded pits—beneath hard, travelled 
rocks, especially,—contain quantities of rich stream-tin-ore. 
At Penny-snap, (Wheal Prosper) in Alternun, a stream-work, 
immediately east of the Drains river, has laid open— 
(1). Peat 2.2... .ccccecsscescerccccrcecce puis eae tetecanalsterenere » o- 7% feet;— 
(2). Angular, subangular, and rude spheroidal, masses of granite, 
schorl-rocks, and quartz ; varying from the size of fine 
sand, to many inches in length, breadth, and thickness, 
all imbedded in pale blue felspathic ley ; from 38 to 6 feet, 
and averaging about......... JoDooroGD0b000000dD000000 5 4 3 
* Mr. John Taylor, Purser of Craddock Moor, M8. 
+ Henwood, Cornwall Geol: Trans: viii, p. 664. 
t Ibid, v, p. 132. 
§ The Ordnance Geological Map (Sheets xxv and xxx, coloured by Sir 
H. T. De la Beche in 1839) indicates no Jode—though one at least has been 
since discovered—north of the, now nearly exhausted, deposit of séream-tin- 
ore long wrought on the Bodmin moors. 
|| Henwood, Cornwall Geol: Trans: iv, p. 61; Ante, p . 194. 
q Of this, valuable fuel, little or no use is made in the neighbourhood. 
