58 On the Paragenetic Relations of Minerals. 
sum of 12s. per ton, for carriage by sea and canal, is entailed, 
forming a total of about £300,000 spent on China-clay and 
stone before they arrive in the potteries, where an immense 
amount of capital is again spent in their manufacture. 
Yearly Expenditure. 
Labour, 7200 men, women, and children, at ls. 6d. 
per diem, ; ; . £197,100 
Carriage of clay and stone to one “of the nearest 
ports, at average price, ; : : : 22,000 
Dues to landowner, ; : ; 14,000 
Dues to proprietors of harbours, : : 2,500 
Cooperage on best clays, : : 5,000 
, £240,600 
Land and canal carriage, at 12s. per ton, : 58,800 
£299,400 
Having thus, as briefly as possible, stated the chief facts 
with which I am acquainted relative to the history, prepara- 
tion, and commercial importance of these articles, and pointed 
out the advantages to be derived, and the field of improve- 
ment which is offered for the contemplation, study, and en- 
terprise of Englishmen, by substituting machinery for the 
great amount of manual labour and cost, at present necessa- 
rily entailed by the existing want of information on this sub- 
ject, I must conclude by again calling attention to the dis- 
tance of these beds from the potteries and their surrounding 
beds of fuel, and suggesting that substitution of the trans- 
fer of materials, at a subsequent period, may considerably 
alter the present state of the central portion of the county, 
and with it the price of the various articles of pottery so ne- 
cessary to our comfort and convenience.—From the Pro- 
ceedings of the Royal Polytechnic Society of Cornwall. 
On the Paragenetic Relations of Minerals. 
Continued from Vol. lvi., No. exii. 
The so-called gelbbleieeze or molybdates of lead are the 
most remarkable products of the decomposition of galena, for 
