penetrate, as to be a discouragement to the reclaiming of the ground. This crust appears to be formed by the agglutinating power of iron in a moist state, with which metal aquatic vegetables abound. The peat-moss, in decomposing, furnishes the metallic solution to the surface beneath. All waters coming from bogs, likewise the stones in the rivulets, denote this; and so do the deposits of umber-like ochre, which are amassed in contiguous situations. Where the subsoil is clay, the moss is deepest; where the moss is shallow, the bottom is either gravelly or else a rubble of rounded stone.

From the Fahan, in a straight line to the Rosses-bay, commences a chain of lakes, some of which are now filled with peat-moss. The principal of these is the beautiful lough of Enogh. This chain seems to denote the former course of the Foyle, which, perhaps, dividing here, as around Derry, in former days, insulated that shistose ridge, which lies between the lakes and the river. On the side of the lakes it is fleshed over with gravel, whose swells and hollows indicate the vortexes, which at a remote period, have shaped these surfaces, betokening the confluence of the Fahan and the Foyle. From the Rosses-bay, by the waterside, and Prehen, to the new buildings, (which place is the terminating point of the county) the soil adjacent to the shore is a shingle or slaty gravel, and the subsoil is shist. The bank above this is steep. But though this is the general character of the soil, no inconsiderable portion of it is, of a stiff blue clay, apparently the decomposition of the softer shists, which sort of soil, having a north-western aspect, is far from affording satisfaction to the farmer.

Still lower than the level already. described, there is extended, within the tide mark, from the mouth of the Fahan to that of the Roe, a vast area of ouzey beach; it seems to be the continually accumulating deposit of the mud or warp, brought down by the rivers, which settles, after a gentle eddy, in this shallow and quiet recess.

Valley of the Foyle.

Under this denomination, I comprehend all that tract of country, laying between the flats of the coast and the interior high lands. It may be said to commence, where an out-branch of the ridge, connected with the Loghermore mountains, pushes towards the beach ; this point very nearly coincides with the barony march, a little above the wood of Walworth.

Turning to the west, the ground, immediately above the flats, is strong loam, forming a soil generally adapted for wheat, barley, flax, or potatoes.

At the openings of the rivulets, somewhat higher, gravelly strata occur. The most inconsiderable streams also have, on their immediate bank, a loamy level, and for the most part, over this, a gravelly ridge. These loams or gravels are straightened or enlarged, proportionably to the extent of the open, through which the channel of the water has found its way.

It frequently happens that, even in the high gravel grounds, strata of clay appear. These last seem to have been the decomposition of the more argillaceous parts of the shist rocks, on which the soil of this district lies; the more flinty parts of the same rocks, having better resisted the action of the elements, remain under the character of gravel and coarse sand.

By experiment on the clay of Fahan-vale, I find that it changes paper stained with vegetable blue to the colour of bright red; an appearance which indicates the presence of an acid. The sub-strata are inclined to the pyritic shist; and still deeper red freestone is found with other indications of coal. It is not improbable, therefore, that this may be the sulphuric acid. Where no river occurs, the general decomposition of soil, on the same level, is that of stiff, cold till, of unequal depth. Through this, the flag-stone of the country appears in detached rocks or continued ranges.

The grounds above this, gradually decline in fertility and depth, till on the summit, there is nothing but quartzy rubble, or peat

moss.

Descending from this high region, the soil gradually improves toward the village of Muff. In this neighbourhood there is a recess, towards the opening of the glen, of excellent soil, or rather of varieties of the best soils: we find gravel, loam, strong clay, and combinations of these in the happiest proportions.

Towards Derry, the swell of Kilnappy is of superior quality; between which swell, and the ridge of Muff, there is a narrow inlet into the vale of the Fahan, which to me has greatly the appearance as if the river, or a part of it at least, had passed in this direction. This flat is filled with mossy loam, and through it issues an inconsiderable stream. The soil from this, round the banks of the Fahan, is rather to be called manageable than fertile, consisting chiefly of ridges or swells of gravel.

On all sides of the Fahan, as it approaches the Foyle, there are not only detached swells, but a continued tire of gravel, perhaps sixty feet higher than the vale, through which it now passes. One is led to think, that these higher ridges of water-rolled materials, which wind with the present course of the river, have been formerly its banks, and even its channel, at some period still more remote.

Near also to where the Fahan falls into the Foyle, commences that extensive flat of bog, which reaches, with one angle interiorly, near to the village of Muff, and stretches coastways from the freeholds of Tully to the manor of Walworth.

Having already noticed the immediate bank of the river Foyle, little remains to be said of the higher lands, proceeding towards the south. There is, however, this difference, that neither are the ridges so high, nor are their descents so prolonged; of coure, there is but little heath on their summits, and less depth of vegetative soil in their declivities.

Let us now pass to the opposite bank of the Foyle. The peninsula

of Culmore is but an assemblage of gravel, intermixed with sands of a very pure quartz. The vegetable surface, where there is tolerany able, is inclined to a peat-moss. It is true of all soils that, where quartzy pebbles predominate, the surface is ungrateful.

At Ballymagard, there is both a shingle of slate, and a cold yellowish clay the subsoil of this, as of the eastern bank, is flag-stone, in great variety; this soil, when well manured, is good for most of the products of husbandry. Trees also thrive in it with great vigour ; and the aspect is favourable.

Pretty nearly of the same description is the lower part of Sir George Hill's demesne at Brookhall; occasionally clay predominates. Again at Sir Andrew Ferguson's, and thence to the southern termination of the ridge, there seems to be an increasing fertility.

This fertile bank is no more, however, than a border, the interior of which is, generally speaking, shallow, cold, and rocky. In other parts, where there is any kind of hollow, it is occupied by peat-moss; the quality of this is not very good as fuel, and, as arable, has been sadly neglected. The most considerable of these mosses is that of the race-course. Other varieties of soil occur; and among these, some swells of light shingle, intermixed with a reddish powder, like the rust of iron.

Between the ridge already mentioned, and that of Penny-burn mill, passing by Troy and Mr. Alexander's farm, there is a flat bottom, well adapted for meadow, which, proceeding by Clogh-glass, ends at Lough Swilly. It is of various breadth, from that of a furlong to that of more than a mile.

The high grounds, bordering this bottom, are less fertile than at first view might be expected; they abound in red ochreous till, which is, apparently, the oxide of the ferruginous shist beneath. There are, however, in sheltered recesses, on the banks of the rivulets, some better grounds; occasionally too, some miniature landscape occurs, where the streams open to the valley.

From the verge of the Liberties, there is a smaller opening,

through which the Craggin-burn traces a demarcation, nearly at right angles with the former. The ridge between this, and the flats of the bog-side, is naturally barren; yet, on the declivity facing the city, manures, with a good aspect, have rendered it far from unproductive, even in high situations. It is still more genial on the descent, where the soil abounds in the shiver of tender slate. From Pennyburn-mill to Miltown-lodge, near the level of the river, it has received a covering of ouze, in many places of great depth and fertility.

The hill of Bally-ougry is like the rest. It includes some rich soils and good farms, the best of which are in the neighbourhood of Mullenan. In this hill also the stony matter is of the shistose varieties.

The city of London-Derry is built on an almost insulated hill, great part of whose soil consists of a stiff, cold, yellowish clay, frequently three feet in depth. Beside this are many varieties: such are the dark and rich vegetable surfaces of the gardens; the mossy soil near the bog-side; and, the tender shiver of slate with mixture of loam all these lay upon strata, comprising many varieties of the shistose class.

In the rear of all these, are the mountainous tracts; hamlets and cultivation here and there interspersed among the arable; the rest is bog and rock.

Vale of the Fahan.

If we confined this district to the banks of the river, from which we derive its name, it would begin at the Sheskin or swamp, under the precipice called the Eagle's rock, at the base of Sawel mountain, and at the march with the county of Tirone. But we must take in with it all the smaller vales, on the banks of the rivulets, which fall into the Fahan, before it winds round from the Bally-mullans into the district of Claudy.

I cannot note any thing very particular on those subdivisions of the country. The solid strata are shist, the summits wild, the declivities, in favourite spots, are not unfertile; and the loams are, as usual, enriched by the deposits from the mountain torrents.

Q