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geological department of the colony…" After a vigorous debate, however, the motion was defeated, principally on the question of ways and means.
The late Rev. C. G. Nicolay contributed in many ways to the knowledge of the geology of the State, and was in charge of the Geological Museum at Fremantle founded by Mr. Hardman, which ultimately became merged into the National Museum.
It was not, however, until 1887 that the Government found itself able to provide the necessary funds for the post of Government Geologist. The appointment was conferred upon Mr. H. P. Woodward, who held the position from 1887 to 1895. During this gentleman's tenure of office he had for his associate Mr. B. H. Woodward, who acted as Curator of the Geological Museum and Assayer to the Department, while in 1893 Mr. S. Göczel was added to the staff as Field Geologist and Mining Engineer. The work of the survey during Mr. Woodward's term of office extended from Albany to Kimberley, though the issue of geological maps in illustration of the various reports seems to have been confined to the later years of the survey. With a limited staff, still more limited appropriation, and the difficulties presented by the vast area of the State the survey under Mr. Woodward was able to issue 21 reports and six geological maps. The work of organizing a more or less systematic geological survey was commenced in 1896, its object being the investigation of the geological structure, mineral resources, mining industries, and underground water supplies of the State. These objects, so far as the resources available will admit, are carried out by means of:— (a) Reconnaissance surveys of those portions of the State about the structure and resources of which little is known; (b) detailed geological surveys of mining centres under active development; (c) chemical and mineralogical examinations of soils, rocks, minerals, and natural waters collected by the field staff, and under certain specified conditions by prospectors and others; (d) palæontological investigations; (e) the maintenance of a geological museum; and (f) the publication of the data acquired in this way.
Topography.—In its broader topographical features Western Australia falls naturally into three geographical divisions:—
The Coastal Plain consists in reality of a fringe round the coast with a more or less gentle slope to the seaward. The plain is formed for the most part of shallow water deposits, sandstones, conglomerates, and thin shales, with occasionally incoherent sands and clays. The plain has a width of 60 or 70 miles in places on the western coast, though in the country at the head of the Great Australian Bight the plain, absolutely devoid of rivers, extends some 200 miles into the interior. The inner margin of the Coastal Plain reaches an altitude of 600 ft. above sea-level in certain localities. The Coastal Plain is separated from the interior by a belt of Hill Ranges.
The Hill Ranges form what may be called the escarpment of the plateau and plains of the interior. They have an average elevation of about 1,200 ft., though isolated ranges reach altitudes of 4,000 ft. above sea-level. This escarpment has either a short or steep slope down to the edge of the Coastal Plain, into which it gradually merges. This belt of country, drained by the rivers of the State, is principally formed of granitic and metamorphic rocks, the decay of which produces excellent soil; it comprises, owing to its rainfall, the principal agricultural districts of the State.
The Plateaux and Plains of the Interior consist of a broken tableland, from which rise isolated hills and ridges of metamorphic rocks, often separated by sandplains of some considerable extent and containing depressions occupied by saline marshes, clay flats, brine lakes, or deposits of salt. There are no rivers and the rainfall is slight. This plateau, which forms the chief mineral region of the State, is mantled by superficial deposits, concealing the underlying rocks, over very wide areas.
Pre-Cambrian, Archæan (?).—The oldest formation in Western Australia is that comprising those granitic, gneissic, and schistose rocks which occupy about one-half of the superficial extent of the State, which is 975,920 square miles, and form the floor upon which the newer strata have been laid down. To the whole of these rocks observers have invariably assigned an Archæan age; this, however, is more inferred than proved. There is only one instance on record at the present time upon which this classification may be considered to have been determined by palæontological evidence. In the Kimberley district certain limestones, sandstones, quartzites, etc., have yielded Lower Cambrian fossils, viz., Salterella Hardmani and Oleuellus (?) Forresti; these fossiliferous beds are considered, and may probably be, newer than the gneissic and schistose rocks in the vicinity. So far as observations have at present been carried no actual junction has been noticed between the schists and the fossiliferous strata, and there is nothing already in the evidence available incompatible with the supposition that the talcose and mica schists and other associated rocks represent much more highly metamorphosed portions of the Lower Cambrian strata. In the absence of direct stratigraphical or palæontological evidence it is convenient for descriptive purposes to adhere to a purely lithological classification and to separate the gneissic, granitoid, and schistose rocks from those in which metamorphism has not been carried sufficiently far to entirely obliterate their clastic character. The great bulk of the interior