422 Chronicles of Science. | July, 
the consumption of tin. This produced naturally a reduction of price. 
Upon this the Cornish mines,—for the purpose of maintaining their 
dividends, preventing calls, and keeping the miners, who have long 
shown a disposition to emigrate,—have been made to yield a quantity 
of tin ore, much in excess of the requirements of the manufacturer. 
At the same time, tin, in unusually large quantities, has been thrown 
into the English market by the Dutch speculators. Banca and 
Billiton tin haye, from their having improved in quality, and being 
cheaper, taken the place of English tin, in many of our large works. 
At the present time the price of tin ore is not sufficient to pay the 
expenses of producing it, yet the mines continue to press their ores 
upon the smelters, in the face of a serious present loss and a too 
evident future failure, which must be ruinous. A monthly metal 
circular now before us says :—“ We have received about 2,000 slabs 
of Straits tin from America, and there is little chance of any demand 
for export hence to that country ; while, owing to the stagnation of 
the tin-plate trade, consumption of tin must have fallen off, and will 
continue to do so for the next two months.” The quantity of tin 
here and in Holland on the 31st of May was as follows, compared 
with the three preceding years :— 
Tons. 
1866 ‘ ‘ ‘ ; ~ : - 10,457 
1865 ’ ‘ : : : : . 10,000 
1864 Z is : 3 : . e 8,690 
1863 an age: y , 5: ae = ‘yi Silas 
In the face of the continental disturbance which threatens, we 
cannot dare to hope for a better report in our next. 
The copper mines suffer from other causes than those influencing 
the tin mines. ‘The present price of English tough cake copper is 
197. per ton below the average of the last sixteen years. The 
influences through which this state of things has been brought 
about are not clear. It has been referred to.the failure of the usual 
demand for copper in India; but this appears quite insufficient to 
create this extreme depression. Our supplies of copper from Chili 
have fallen off in consequence of the war with Spain, and for some 
time to come we cannot expect any large quantity of copper from 
that country. The deficiency will certainly not be made up by any 
increased supplies from other parts of the world. We may, conse- 
quently, hope, in a little time, to,see our English copper mines 
becoming more profitable than they have been for some time past. 
Tons. 
The tin-mines of Cornwall and Devonshire produced, in 1865, of Black 
Tin ‘Tin Ore) . . : . . . . . - 15,686 
The production in 1864 having been . ° A ‘ . «| a2 
The quantity of Copper Ore produced from the mines of Cornwall and 
Devonshire in 1865 was. : : f . . S - 159,406 
The production in 1864 being . . » 163,336 
The Swansea sales of Irish, Welsh, and Foreign Copper Ores were, in 
1865 : 2 : . . ‘ : ; : : . Bao 
Against, in 1864. . . . : . ‘ . ‘ . 32,413 
