notes to letter iii.
e1 ↑ This fossil is not what White supposes, but is a different species, belonging to the upper greensand, known as Ostrea carinata.
e2 ↑ The Ammonite is a very striking-looking fossil, and a common one. When I was a small boy I used to delight in playing with a very large one belonging to my father's collection, which would take to pieces, each section of the shell being loose, showing the formation admirably.
LETTER IV.
As in a former letter the freestone of this place has been only mentioned incidentally, I shall here become more particular.
This stone is in great request for hearth-stones, and the beds of ovens: and in lining of lime-kilns it turns to good account; for the workmen use sandy loam instead of mortar; the sand of which fluxes,[1] 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 chiseled smooth, it makes elegant fronts for houses, equal in colour and grain to 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, but laid in the same position that it grows in the quarry.[2] On the ground abroad this firestone will not succeed for pavements, because,
- ↑ There may probably be also in the chalk itself that is burnt for lime a proportion of sand: for few chalks are so pure as to have none.
- ↑ To surbed stone is to set it edgewise, contrary to the posture it had in the quarry, says Dr. Plot, "Oxfordshire," p. 77. But surbedding does not succeed in our dry walls; neither do we use it so in ovens, though he says it is best for Teynton stone.
