The country to the eastward of the Shoalhaven river, that is to say between it and the sea-coast, is very wild and mountainous. The higher part including Currocbilly and the Pigeon house (summits) consists of sandstone passing from a fine to a coarse grain, occasionally containing pebbles of quartz, and in some of the varieties numerous specks of decomposed felspar. The lower parts of the same country, according to the rocks seen in Yalwal creek, consist of granite, basalt, and compact felspar. Nearer the coast a friable whitish sandstone affords but a poor soil, except where the partial occurrence of decomposed laminated felspar and gneiss produced one somewhat better. This country comprises the county of St. Vincent, bounded on one side by the Shoalhaven river and on the other by the sea-coast. The southern portion of that county affords the greatest quantity of soil available either for cultivation or pasture; although around Bateman Bay, which is its limit on the south, much good land cannot be expected as Snapper Island at the entrance consists of grey compact quartz only, with white veins of crystalline quartz. UPPER SHOALHAVEN. The country on the upper part of the Shoalhaven river comprises much good land. The river flows there nearly on a level with the surface and resembles an English stream. The temperature at the elevation of about 2000 feet above the sea is so low even in summer that potatoes and gooseberries, for both of which the climate of Sydney is too hot, grow luxuriantly. A rich field for geological research will probably be found in that neighbourhood. CARWARY. In a hasty ride which I took as far as Carwary in 1832, I was conducted by my friend Mr. Ryrie to a remarkable cavern under white marble where I found trap; a vein of ironstone of a fused appearance; a quartzose ferruginous conglomerate; a calcareous tuff containing fragments of these rocks; and specular iron ore in abundance near the same spot. But still further southward and on the range separating the country at the head of the Shoalhaven river from the ravines on the coast, I was shown an antre vast which, for aught I know, may involve in its recesses more of the wild and wonderful than any of the deserts idle which I have since explored. VAST SUBSIDENCE ON A MOUNTAIN THERE. A part of the surface of that elevated country had subsided, carrying trees along with it to the depth of about 400 yards, and left a yawning opening about 300 yards wide resembling a gigantic quarry, at the bottom of which the sunken trees continued to grow. In the eastern side of the bottom of this subsidence a large opening extended under the rock and seemed to lead to a subterraneous cavity of great dimensions. GOULBURN TOWNSHIP. November 1.