204 JOURNAL OF THE PLYMOUTH INSTITUTION. 
raised in Devon and Cornwall in 1872, delivered at the works 
where used, would be nearly half a million sterling. The con- 
sumption last year was, I believe, considerably greater than in 
1872, and it appears to be still increasing. As a large proportion. 
of the value consists in the cost of carriage, any improved facility 
of conveyance facilitates its production. On this account, the 
opening of the South-Western line of railway, which passes through 
a portion of Dartmoor, hitherto inaccessible, will be likely to lead 
to the undertaking of new works for its extraction and preparation. 
In addition to the kaolin, or china clay, there were also produced 
in the district about Bovey Tracey and Newton 52,141 tons of 
pipe and potter’s clay, conveyed by water from Newton to Teign- 
mouth, and there shipped. Within the last four or five years an 
extensive series of manufactories have sprung up on Hingston 
Down, near Calstock, and some other localities in Cornwall, of fire- 
brick made from a coarse clay not fine enough for the production of 
china clay. Some quantity of clay is consumed on the spot at Bovey 
Tracey in the manufacture of fine fancy pottery, and at Watcombe, 
near Torquay, for the production of Terra Cotta goods. There is a 
small pottery still at work at Coxside, producing rough brown and red 
‘ware, and a few common brick manufactories may be found spread 
over the two counties. In Robert Hunt’s ‘ Mineral Statistics” a 
curious particular appears; viz., 375 tons of candle clay consumed 
in one year simply for the purpose of wrapping around and holding 
candles burnt for miners’ underground purposes. The clay for this 
purpose is obtained preferably from the high ground of St. Agnes 
or St. Ann’s Beacon. | 
I have already devoted so much time to the consideration of 
water and clays that I must content myself with the bare enume- 
ration of some of the other earthy minerals which constitute sources 
of wealth in the two counties, such as limestones, marbles, slates 
(roofing and common), granites, greenstones, porphyries, elvans, 
serpentine; sands from rivers used for building and other purposes; 
sea-sand used as a source of lime, on account of the débris of shells 
contained in it, for agricultural purposes ; muds, or silts, used for 
agricultural purposes, or capable of being employed in the manu- 
facture of cements. 
