Geological Structure of Malta.—The Island of Malta is entirely composed of Tertiary aqueous rocks, which lie in a nearly horizontal position, but which, being traversed by several faults, are found at very different levels. This horizontal position of the strata is interesting, as it is seldom seen in small islands situated so far from the main land; and it is probably to be accounted for by supposing that any unequal pressures which might have occurred during the upheavels of the Island, expended themselves in the production of faults, instead of inclinations and contortions of the strata.

The Summit of the hill, about two miles form the station, on the property of Arthur Peel, Esq., M.P., consists of yellow and brown sand, with much iron; and the harder beds of the latter, where they form a stone, are composed largely of small pebbles of quartz, sandstone, and mica. In these the phosphatic nodules are found. Generally they lie at a variable depth from the surface—in some cases cropping out; but, in others, they prevail at a greater depth, with a capping of soft sand from three to four feet, but none have been met with below six feet from the top.

In a former article I endeavoured to show that the more abrupt inequalities of the earth's surface, so far as they consist of escarpments with their associated phenomena, are chiefly due to the former action of the sea. Before proceeding to consider the origin of Valleys, I find it necessary to refer to a statement I made in the last article about Raised Beaches (page 69). My object was merely to show that the preservation of numerous terraces in the Cretaceous districts of Wilts and Dorset furnished an evidence of limited subaërial denudation since these terraces were formed. The terraces to which I alluded, principally occur at comparatively low levels; and that they are raised beaches can, I think, be clearly proved. But this is not necessary, so far as the present controversy is concerned; for the preservation of terraces in gravel (more easily worn away than chalk, according to the subaërialists), which all admit are either raised sea-beaches, or glacial-lake-beaches (such as those of Glenroy), afford an equally convincing proof of the impotence of rain as a denuding agent.

It was publicly stated not long since that of all the Silurian strata there were no two so closely connected as the Liandilo and Caradoc groups. At the time this seemed a bold assertion, considering the great number of genera which were then thought to originate in the latter, not being known in the former. Some new forms, however, that have lately come to light from the Llandilo flags, shoe the connection between the two strata to be closer than it formerly appeared.

Three minerals, Nephrite, Agalmatolite, and Steatite, are much used by the Chinese for small articles of ornamental sculpture. The examination of several oriental specimens of these substances in my collection has led to some interesting results.