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house, permission was given me to examine for this article; and though I was disappointed as to the fossil, I was highly gratified with the sight of several of the shells themselves in high preservation. This bivalve is only known to inhabit the Indian ocean, where it fixes itself to a zoophyte, known by the name Gorgonia. The curious foldings of the suture the one into the other, the alternate flutings or grooves, and the curved form of my specimen being much easier expressed by the pencil than by words.
Cornua Ammonis are very common about this village. As we were cutting an inclining path up the Hanger, the labourers found them frequently on that steep, just under the soil, in the chalk, and of a considerable size.* In the lane above Wellhead, in the way to Emshot, they abound in the bank in a darkish sort of marl; and are usually very small and soft: but in Clay's Pond, a little farther on, at the end of the pit, where the soil is dug out for manure, I have occasionally observed them of large dimensions perhaps fourteen or sixteen inches in diameter. But as these did not consist of firm stone, but were formed of a kind of terra lapidosa, or hardened clay, as soon as they were exposed to the rains and frost they mouldered away. These seemed as if they were a very recent production. In
* This path, or bostol, as it is locally called, is an oblique cutting, running up the north-east side of the hill, but the path more commonly used is formed by a series of zigzag steps, commencing at the south-east extremity of the village, Mr. White's house being on the right hand. This is a moderate-sized country mansion, surrounded by a field, and enclosed by a ha-ha, which abuts on the wooded slopes of the Hanger. The east end of the hill, up which this path ascends through stunted bushes, is only occupied by a few straggling trees.-ED.
the chalk-pit, at the north-west end of the Hanger, large nautili are sometimes observed.
In the very thickest strata of our freestone, and at considerable depths, well-diggers often find large scallops or pectines, having both shells deeply striated, and ridged and furrowed alternately. They are highly impregnated with, if not wholly composed of the, stone of the quarry.
S in a former letter the freestone of this A place has been only mentioned inciden1968 tally, I shall here become more particular.
This stone is in great request for hearthstones, and the beds of ovens : and in lining of limekilns it turns to good account; for the workmen use sandy loam instead of mortar; the sand of which fluxes, and runs by the intense heat, and so cases over the whole face of the kiln with a strong vitrified coat like glass, that it is well preserved from injuries of weather, and endures thirty or forty years. When chiselled smooth, it makes elegant fronts for houses, equal in colour and grain to the Bath stone; and superior in one respect, that, when seasoned, it does not scale. Decent chimney-pieces are worked from it of much closer and finer grain than Portland; and rooms are floored with it; but it proves rather too soft for this purpose. It is a freestone, cutting in all directions; yet has something of a grain parallel with the horizon, and therefore should not be surbedded—that is, set edgewise, contrary to its position in the quarry—but laid in the same position that it occupies there. On the ground abroad this firestone will not succeed for pavements, because, probably, some degree of saltness prevailing within it, the rain tears the slabs to pieces.* Though this stone is too hard to be acted on by vinegar; yet both the white part, and even the blue rag, ferments strongly in mineral acids. Though the white stone will not bear wet, yet in every quarry at intervals there are thin strata of blue rag, which resist rain and frost; and are excellent for pitching of stables, paths, and courts, and for building of dry walls against banks; a valuable species of fencing, much in use in this village, and for mending of roads. This rag is rugged and stubborn, and will not hew to a smooth face; but is very durable: yet, as these strata are shallow and lie deep, large quantities cannot be procured but at considerable expense. Among the blue rags turn up some blocks tinged with a stain of yellow or rust colour, which seem to be nearly as lasting as the blue; and every now and then balls of a friable substance, like rust of iron, called rust balls.t
In Wolmer-forest I see but one sort of stone, called by the workmen sand, or forest-stone. This is generally of the colour of rusty iron, and might probably be worked as iron ore; is very hard and heavy, and of a firm, compact texture, and composed of a small roundish crystalline grit, cemented together by a brown, terrene, ferruginous matter; will not cut without difficulty, nor easily strike fire with steel. Being often found in broad flat pieces, it makes good pavement for paths about houses, never becoming slippery in frost or rain; is excellent for dry walls, and is sometimes used in buildings. In many parts of that waste it lies scattered on the surface of the ground; but is dug on Weaver's Down, a vast hill on the eastern verge of that forest, where the pits are shallow, and the stratum thin. This stone is imperishable.
* “Firestone is full of salts, and has no sulphur: it must be close grained, and have no interstices. Nothing supports fire like salts; saltstone perishes when exposed to wet and frost."-PLOT's Staff. p. 152.
† Supposed to be decomposed iron pyrites. Ragstone is a earbonate of lime, with a little magnesia, earthy matter, oxide, and carbonaceous matter.--Ep.
From a notion of rendering their work the more elegant, and giving it a finish, masons chip this stone into small fragments about the size of the head of a large nail; and then stick the pieces into the wet mortar along the joints of their freestone walls : this embellishment carries an odd appearance, and has occasioned strangers sometimes to ask us pleasantly, “whether we fastened our walls together with tenpenny nails."