the author of Travels in Sicily, and d the Survey d the Mediterranean recently published by the Admiralty, in- forms me, that he hot seen these concretions in Calabria, and on the coasts of the Adriatic ;?but still more remark* ably in the narrow strip ofweceut !and, (called the Place. a,) which connects Leucadia, one of the Ionian Islands, with the continent, and so much resembles a work of art, that it has been considered as a Roman fabric. The stone composing this isthmus is so compact, that the best mill-stones in the Ionian Islands are made.from it; but it is in fact nothing more than gravel and send cemented by calcareous matter, the accretion of which is supposed to be rapidly advancing at the present day. The nem'est approach to the concreted sand-rock of Aus- tralia, that ? have seen, is in the specimens presented by Dr. Danbeny to the Bristol l.nstituti.on, to accompany his excellent paper on the geology of Sicily � which prove that the arenaeeous breeeia of New Holland is very like that which occupies a great pen. of the coast, almost entirely around that island. Some of Dr. Danbeny's specimens .from Monte Calogero, above Sciaeea, consist of a breeeia, con- tainin? angular fragments of splintcry limestone, united by a cement, composed of minute grains of qu .a?Mse-sand dis- seminated in a calcareous paste, resembling precisely that of the breceia of Dirk Hartng's Island: and a compound of this kind, replete with shells, not far, if at eli, different from existing species, Rlls up the hollows .in most of the older'rocks of Sicily; and is described as occurring, in several places, at very considerable heights above the sea. Thus, near Palermo, it constitutes hills some hundred feet in heig?t;mnear Girgenti, all the most elevated spots are �F, dinb. Phil. Jour. 18?. pp. !16; 117, !18, and liZocl Goo8Ic
�
