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Rh North, and Cape Beaufort on the South, but connexion between these eruptive masses has not been determined.

Two geological maps of the South-Western part of the Colony have been published; one by F. H. Gregory (Arrowsmith, London, 1860) including the Gascoigne river, which is now very scarce, and the other by H. Y. L. Brown, giving the result of his surveys when employed as Government Geologist during the years 1870-73, which will be found with detailed maps, sections, &c., in the volumes of Council papers published by the Government during the years 1872-73. This of course is the more valuable, as of later date, and the work of a professional Geologist, but Mr. Gregory's map, including a much larger area both to the North and East, and marking the appearance of granitoid rocks in the river courses and elsewhere, as well as many erupted masses not included in Mr, Brown's map, gives valuable assistance in considering the general geological features of the Colony. Granitoid rocks appear in great masses, forming capes and headlands on the Southern Coast, as also in dome-like elevations and bare escarpments, on the summits and sides of the principal water-sheds of the country. These, in many places, and more especially from Champion Bay to the Murchison River, are traversed by dykes of greenstone and similar rocks, in which rich lodes of copper and lead are found; and on the surface, in other places, there are extensive deposits of brown hæmatitic iron ore. Silver exists in small quantities in the lead ores, and gold has been found both in alluvium and quartz reefs, but not as yet in quantity to make its working remunerative. Among the erupted schistose rocks on the Irwin, Phillips, and Fitzgerald rivers have been found, as probably there will be elsewhere, strata