The Kentish Ragstone is a source of very considerable trade to Maidstone, and gives employment to many workmen. Several barges are constantly engaged in conveying to the coasts of Kent and Sussex, in the marshes of which it is very extensively employed for the banks or sea-walls. In Romney Marsh and on the eastern side of the Isle of Sheppey a large expenditure is yearly incurred in thus protecting large and valuable tracts of land from the ravages of the sea. The ragstone is also extensively used as a road-stone and for buildings, large quantities of the stone being sent to London and other places especially for the former purpose. A small quantity is burnt into lime of a very superior quality; but the abundance of chalk in this neighbourhood, and the greater cheapness of that rock, prevents the general use of the stronger but more costly stone-lime.

Many handsome buildings in Maidstone and other places in the county are built of it. Of these in Maidstone may be mentioned the new gaol, the lunatic asylum, and the new church. Of ancient buildings constructed of it are the old parish church of All Saints, the Episcopal Palace and College. Many of the London churches, and nearly all of those on the banks of the Thames and Medway, have a great proportion of this stone in their walls; and proofs of its durability and early application to building purposes may be seen in the present condition of Allington and Rochester castles, and most of the bridges from Aylesford to Tunbridge.

The lower mandible of a chimæra—the first discovered in the Lower Greensand—is now in the collection of Sir Philip Egerton, who informs me it belongs to the species Ischyodus Agassizii. Since this discovery I have met with many more specimens, some of smaller size; but, from the difficulty of extracting them from the stone, I have never succeeded in getting one so perfect. Several good specimens have been procured from the Lower Chalk at Burham. The chimæra approaches in form to the shark tribe, but it is far from being so ravenous in its disposition. Recent species are found in the Arctic and in some of the European seas, and attaining the length of two or three feet. Being often taken in the company of the herrings in their migrations, it has thus gained the patronymic of “king of the herrings.” The mouth of this odd-looking fish is furnished with hard and undivided plates instead of teeth, four of which are placed on the upper and two on the lower jaw.

Fossils are very rare in the succeeding “rugged flint layers,” which have an average thickness of eight inches.

In Vol. I of the ‘Geologist,’ at page 249, was published a paper on the preparation of sands, clays, and chalk, for microscopical purposes, under the heading of “Geological Manipulations;” and, as both pleasure and geological profit are to be obtained from the exact examination of various fossil-bearing deposits, both as to their constituents and their contents, I beg to offer you an example of the results of such an examination of some tertiary beds from Bracklesham. These notes I have had by me several years, and their short-comings are so great in some respects that I should not send them, were it not that they may serve as a plan to some young careful observers who might feel inclined to enter upon the strict examination of some definite series of fossiliferous strata. What the series under notice is deficient of, is a statement of the exact relationship of these several deposits, examined nearly twenty years ago. I received the materials at that time from a friend who was collecting “Bracklesham fossils,”—a term which will be more definite, now that the Rev. O. Fisher, F.G.S., has indicated the exact limits of the Bracklesham formation.

The specimens were chiefly, I believe, from Bracklesham and Selsea; but some may have been brought from the Isle of Wight. By the presence of certain fossils, however, in some of the deposits, their exact place may probably be determined. However deficient in these stratigraphical requirements the following account of the deposits may be, they will serve the purpose here intended, namely, to show young beginners what to look for in sands and clays. Instructions have been already given as to how such materials are to be examine, in the first volume, p. 249.

The mountainous district known as the Eifel, or Eifel-Gebirge, in Rhenish-Prussia, is, as all geologists knowr, famous for the numerous well-preserved craters of extinct volcanos and for the lava-streams, scoriæ, trachyte, and basalt connected therewith.

The English reader will find a short account of the tertiary and volcanic rocks of the Eifel in Lyell’s ‘Manual of Geology,’ chapter xxxi.; and a good geological map of the Eifel and neighbouring districts is appended to a paper, by Sedgwick and Murchison, on the Rhenish Provinces, in the Transactions of the Geological Society, 2nd series, vol. vi. part 2. In the Eifel there are two extensive areas, in which volcanic activity has been especially intense.

In a tolerably deep ravine, surrounded by trees and brushwood growing in wild profusion, was, until lately, a cave, in that member of the carboniferous formation locally called the “Great Limestone,” and situated about one mile and a quarter north from the town of Stanhope, in the county of Durham. The limestone is now being worked for the purpose of supplying the Weardale Iron Company with a flux used in the operation of smelting their ironstone; and consequently the cave has been laid bare to the light of day.

The cave was much visited a few years ago, both by strangers and persons living in the locality, but probably few of the visitors ever studied the excavating forces by means of which the cave was hollowed out of the solid limestone, and fewer still, if any, would think that they were treading on a primeval burial-place.

Doubtless the excavation must be mainly due to aqueous agency, but a reference to Sir Charles Lyell's ‘Principles of Geology,’ Professor Phillips's ‘Treatise on Geology,’ and Richardson's ‘Geology,’ shows that our leading writers on this subject consider that the first cause of a cavern must have been a fracture in the limestone rock, consequent on the upheaval of the strata, and that water then finding access to the crack, would wear it out to its present dimensions.