tain or plateau destruction and the contemporaneous plain building to the west. Acknowledgments.-Although the writer is responsible for the main portion of the model, nevertheless, he is under a deep obligation to Mr. R. H. Cambage, Mr. Statham and Dr. W. G. Woolnough, for supplying information without which the model could not have been presented satisfactorily. Thus Mr. Cambage supplied the information from which the Nandewar and the Goulburn River areas have been figured, while Mr. Statham furnished accurate sections, prepared for the Public Works Department, dealing with the areas from the head of the Tweed to Lismore, from the Dorrigo to the Orara River and along that stream, and from Grafton to Glen Innes. Dr. Woolnough also furnished information concerning the Tweed and Richmond areas. The writer desires to return cordial thanks to Mr. J. W. Turner, Superintendent of the Sydney Technical College, for the preparation of casts of the model to be supplied to the Departmental Museum, the University and the Federal Meteorologist, and to Mr. A. W. Gullick, the Government Printer, for the block for the plate illustrating the present note. 1. Scale of Model. The Model. 2. Geographical Notes. 3. Biological Notes. 1. Scale of Model.-The horizontal and vertical scales are not alike, the former being 16 miles to the inch and the latter 8,000 feet to the inch. By this method the model can at most furnish an approximate idea of the real nature of the New England topography, inasmuch as only the larger "facts of form" can thus be represented, the vertical element being so distorted that there is no opportunity to represent details. Thus the rivers and their main tribu J-August 7, 1912. taries are illustrated by the model, but the gulleys and gorges innumerable which break up the continuity of the great cañon and mountain walls are not shown. Similarly, only the larger hills and mountains are represented, the legions of smaller elevations being merely indicated by a generalised type of mildly roughened topography. Accuracy of representation can only be obtained after the completion of detailed topographic surveys. The general appearance of the New England surface, as gained from a commanding eminence, has, however, been illustrated, as also the general appearance of the wild eastern topography afforded to the traveller as he surmounts the ridges which swell out from the ravines. In the model the cañons and ravines are represented as limited in number, whereas, in reality, the traveller is overwhelmed by the wealth of branching ravines and overlapping spurs as he views the jungle-laden depths from some forest-clad spur or eminence. 2. Geographical Notes.-The main topographic divisions illustrated by the model are the great Plateau of New England, the Coastal Region and the Inland Plains. (a) The Plateau.-It is evident that the plateau must formerly have had a much greater extension than it possesses at present. The portion untrenched by cañons and ravines consists mainly of a gently warped and a maturelydissected surface, above which, in various localities, rise other small plateaus. At the heads of the Namoi, the Macleay and the Manning Rivers, the general plateau surface is almost 4,000 feet in height, thence towards Armidale it possesses a very gentle dip. At the latter locality the plateau has a general height of about 3,500 feet, while the average height of the broad mature valley bases, which mildly roughen this level, is about 3,250 to 3,3001 All heights unless otherwise specified are referred to mean sea level at Sydney. |