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coast as far as Albany contains numerous caves that have been proved to contain varying quantities of guano, but which yet remain to be worked. Without more or less detailed surveys it is obviously an impossibility to make even a rough estimate of the available deposits, which, of course, are exhaustible, or to attempt any forecast as to the life of the phosphate deposits.

Artesian Waters.—Western Australia possesses a large tract of country which actual boring operations have shown to be artesian water-bearing. Artesian water has been found in the Eucla, South-West, North-West, and Kimberley Divisions. The water-bearing strata in the Eucla Division consist of sandstones, sandy shales, glauconitic marls, etc., lying beneath a great thickness of white limestone. These beds have been proved by their fossil contents to be the equivalents of the Lower Cretaceous strata of Eastern Australia. Five bores have been put down in this plateau, and the water rises in them to a height equal to that of sea-level. The first bore, situated not far from the sea coast at the foot of the tableland, was carried down to a depth of 2,041 ft. At a depth of 900 ft. the strata pierced consisted of limestone, the remainder being mud, stones, shales, etc. At 2,041 ft. a supply of good stock water was encountered, which issued from a standpipe 2 ft. above the surface, at the rate of 5,700 gal. per diem. The water-carrying beds in the Eucla Plateau have a prevailing dip toward the Great Australian Bight.

The most important portion of the South-West Division when viewed in the light of the occurrence of artesian water is the Coastal Plain, which practically extends from 29° to 33° southern latitude. The plain is really formed by a fringe of strata round the coast, with a more or less gentle slope to the seaward. It is from the strata underlying this plain that the supplies of artesian water have been obtained. The structure of the Coastal Plain differs in many important respects from the typical areas in which artesian water has been obtained in other portions of Australia. The strata are horizontal, or nearly so, though occasionally there is a slight local dip of about 5 to 8 deg. The effect of this horizontality is shown in the fact that the water-carrying beds do not crop out on the surface near the eastern margin of the plain, but impinge directly against that portion of the main range which is concealed from view. The strata do not attain a uniform thickness throughout, but are disposed in the form of lenticular beds, some of which appear to be of exceptionally absorptive properties. The mean annual rainfall of the Coastal Plain is from 20 to 30 in., a precipitation which is considerable. No systematic observations have as yet been undertaken to ascertain the actual discharge of the numerous rivers which flow across the plain, so that no estimate of the amount of water available for absorption can be even arrived at. That such must be considerable is obvious from the data collected and tabulated with reference to the discharge of the Helena River, near Perth. The observations were made at two stations—one near Midland Junction, the other near Greenmount. The westernmost locality is situated on the outcrop of the permeable strata of the Coastal Plain and the other on the crystalline (or impermeable) rocks. From the figures obtained it appears that about 22,000,000,000 gall. of water per annum disappeared underground and is capable of being reached by wells. The conditions which prevail over large areas of the Coastal Plain demonstrate that rivers of a much larger catchment discharge their drainage into the plain, and it is therefore only reasonable to assume that a large proportion of the water from the catchments also disappears beneath the surface and helps to feed the artesian reservoir below. So far as the latest official data with reference to the extent of boring operations show there are forty-eight artesian wells in the South-West Division reaching an aggregate depth of 39,378 ft. and yielding a total flow of 15,521,800 gall. per diem.

A considerable portion of what may be called the coastal area of the North-West Division is of considerable economic importance by reason of the fact that artesian water has been found to occur over a wide area, and in consequence of the discovery of which the stock-carrying capacity of this excellent pastoral district has been materially increased. This artesian area extends, so far as determined by such geological mapping as has been carried out, from the mouth of the Murchison River to somewhere about North-West Cape, thus covering about 6° of latitude with a maximum width of over 130 miles. The strata occurring in the valley of the Gascoyne River consist of representatives of the Palæozoic, Mesozoic, Tertiary, and Post-Tertiary ages, all of which are of importance from the hydrological standpoint. The basal beds of the Palæozoic strata, which carry a considerable portion of the artesian water in this part of the State, consist of conglomerates, sandstones, and limestones. These when viewed broadly are found to have a very gentle dip to the westward, which carries them below the level of Shark Bay. These beds have been pierced in the experimental bore put down at Pelican Hill (Bibbawarra), near Carnarvon, and which was carried down to a depth of 3,011 ft. The record of this importnat bore showed that the first 150 ft. comprised clays and limestone of newer or Post-Tertiary age; Middle Tertiary marls and shales were passed through to a depth of 1,238 ft.; Mesozoic (and possibly Cretaceous) clay shale and glauconitic sand stone down to 1,361 ft.; while the balance of the beds, 1,650 ft. in thickness, revealed limestone, black shale, and sandstone as determined by the organic remains of Permo-Carboniferous age. This Pelican Hill bore is of