- 2. The Lake district, extending to the head waters of the Greenough and Murchison.
- 3. The Coast district, including the basins of all rivers South of the Greenough.
To these must be added the Coast districts of the North and South, including the basins of all rivers felling into the sea in those directions.
These divisions accord well with what is known of the Geology of the Colony, as a line drawn N.N.W. from Point Culver at the Western end of the Great Australian Bight will pass along the Western limit of the granitoid rocks on the edge of the great desert, and strike the mountains at the head of the Fortescue; while a similar line drawn from Fowler's Bay, at the head of the Bight, where Mr. Delisser found granite, will pass between Mounts Elvire and Fort Mueller granitic rocks, on Forrest's track, near the Eastern edge of the great desert. It is also apparent that a similar line, drawn from the Eastern shore of the Great Bight, would come out on the Northern coast in the deep indentation to the East of Cape Londonderry. These lines, and others drawn at right angles to them, will also be found to correspond generally with the coast line, so that, within a parallelogram of 1000 miles in length by 700 in breadth, which may form the normal figure of the Colony, its area to the West of a line drawn from King's Sound, S.S.E., would be included. If, however, the Southern limit of such a parallelogram were to be a line drawn through Point Culver, the Western coast limit of surface granite, in the desert district, it would pass to the North of that great mass of oolitic rock which appears on the shore of the Great Bight; and this exclusion would be consistent with the fact that this formation is exceptional, and differs from all other known geological formations in the Colony; the
