Reviews — Dr. A. P. Goleinan — The Nickel Industry. 567 



The headings of the chapters run as follows : Study of Nature ; 

 Substance of Nature ; Energy, the Power of Nature ; the Earth 

 a Spinning Ball; the Earth a Planet; Solar System; Atmosphere, 

 its Phenomena ; Climates ; Weather and Storms ; Hydrosphere ; 

 Ocean Bed ; Crust of Earth ; Action of Water; Record of the Rocks ; 

 Continental Area ; Life ; Man. The maps are clearly printed and 

 valuable, and show magnetic conditions, earthquake regions and 

 volcanoes, isotherms, isobars, winds, rainfall, salinity of oceans, con- 

 figuration of globe and coastal lines, drainage areas, evolution of 

 continents, ocean-surface isotherms, coral reefs, rising and sinking 

 coasts, vegetation zones, and biological regions. 



It is one of those handy volumes the usefulness of which becomes 

 daily more apparent, and the [irice greatly assists its recommendation. 

 It has an index, but the worker will add to this for his own con- 

 venience such words as maelstrom, dunes, travertine, stalagmite, 

 stalactite, metric system, zero, rigidity, atomic weight, lodestone, 

 etc., which to publishers do not seem to be of any importance. 



IV. — The Nickel Industry : with special eefekence to the 

 Sudbury Region, Ontario. By A. P. Coleman, Ph.D., F.R.S. 

 Department of Mines, Canada, No. 170, pp. vii -{■ 206, with 

 14 text-figures, 63 plates, and 8 coloured maps. Ottawa, 1913. 



DURING recent years the Canadian Department of Mines has 

 issued several useful monographs on various minerals of 

 economic importance which occur and are mined in the Dominion, 

 and the present volume adds another to this series. The group of 

 mines near Sudbury produces two-thirds of the world's supply of 

 nickel, the amount for the year 1910 being 18,636 tons of metal, 

 together with 9,630 tons of copper, of a total value of rather over 

 one million pounds sterling. The ore here consists of an intimate 

 mixture of pyrrhotite (magnetic pyrites), pentlandite (a sulphide of 

 iron and nickel), and copper-pyrites, more or less intermingled with 

 rock-forming silicates. It occurs at the base of an intrusive sheet 

 or huge laccolite of igneous rock, and it passes imperceptibly into 

 this. This sheet, consisting of norite in its lower portion and 

 graduating upwards into micropegmatite, is intrusive between the 

 crystalline rocks of the Laurentian and the sedimentary rocks of 

 the Upper Huronian. Its outcrop forms the rim of an oval basin 

 measuring 36 miles along the major axis and 16 miles across, and 

 the several mines in which the nickel ore is worked are situated 

 along the rim of this basin. We have here clear evidence of 

 magmatic differentiation on an enormous scale ; the acid rock 

 passing downwards into basic rock, whilst at the bottom of all are 

 the heavy metallic sulphides. 



An outline of the physiography and general geology of the district 

 and a mineralogical description of the ores is followed by an historical 

 sketch of the mining industry, and detailed particulars relating to 

 each of the several mines now working. Although the occurrence 

 of nickel in this district was first recorded in 1856, it was not until 

 1884, when large bodies of ore were exposed in the cuttings of the 



