338 Chronicles of Science. [ April, 
increase of 4,500,000 tons in the last ten years. The production of 
pig-iron in 1862 was 1,053,000 tons, which was double the quantity 
made in France six years previously. Our space will not allow of 
our quoting from the papers by A. Burat, E. Bede, and others on the 
special subjects which belong to this division of our Chronicle. We 
cannot, however, refrain from directing our mining engineers to a 
“Note sur quelques perfectionnements introduits dans lexploitation 
des Mines,” par Jules Havrez, which appears in the August part of 
the ‘Revue Universelle. It appears to us to offer many valuable 
suggestions, by which they might profit. The ‘ Etudes sur lAcier,” 
by M. de Cizancout, in the ‘ Annales des Mines,’ is a communication 
deserving the attention of our metallurgists. Professor Rivot has an 
instructive memoir on the ‘ Veins of Argentiferous Galena’ of Vialas 
(Lozére). To our miners this paper should be a model, upon which 
they might build a record of their own experiences. 
In the report recently published of the progress of the geological 
survey of Canada, under the direction of Sir William Logan, there 
is much matter of especial mineralogical interest. The chapters 
devoted to the consideration of ‘mineral species” may be consulted 
with advantage. They make us acquainted with several modified 
conditions of known minerals, and with a few which appear to be new 
varieties. Amongst the metallic minerals which have been discovered 
in such quantities as to give them a commercial value we find 
nickel and cobalt, chromic iron, iron ores in considerable variety, 
copper, lead, silver, and gold. The magnetic oxide of iron has been 
found in great abundance, this valuable mineral giving 72:4 parts of 
iron, and 27-6 parts of oxygen. A satisfactory description of the lead 
and copper mines of Canada is given by the Geological Surveyors. It 
would, however, have been interesting and important if the present rate 
of production had been ascertained. As Canada is destined to become 
a great mineral-producing country, the progress of its economic geology 
would have formed a very appropriate addendum to the report on its 
scientific geology.* 
Gold occurs in this colony, both in veins and in the drift. Some 
idea of the value of the auriferous deposits may be formed from the 
following quotation :— “It has been shown that the washing of the 
ground over an area of one acre, and with an average depth of two feet, 
equal to 87,120 cubic feet, gave in round numbers about 5,000 penny- 
weights of gold, or 1,88, grains to the cubic foot, which is equal to 
1? grain of gold to the bushel.” Several other minerals useful in the 
arts and manufactures are succinctly noticed, and the occurrence of 
plumbago especially described, this mineral occurring in a state of 
considerable purity. 
A very interesting description of the production of the bitumens, 
especially of the petroleum of Gaspé, is, at the present time, important. 
* «Geological Survey of Canada. Report of Progress from its Commencement 
to 1863, illustrated by 498 Woodcuts in the Text, and accompanied by an Atlas 
of Maps and Sections.’ Officers of the Survey—Sir William Logan, Alexander 
reds T.Sterry Hunt, and E. Billings. Montreal: Dawson Brothers. London: 
alliere. 
