8 NATURAL HISTORY OP SELBORNE. 
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 Wall-head, 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 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. 
LETTEE ly. 
TO THE SAME. 
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,* 
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 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, but laid in the 
same position that it grows in the quarry .f On the ground abroad this 
of Selborne, refers it to the Ostrea carinata of Lamarck, a species peculiar to the 
green-sand formation, iipon which the village of Selborne is built^ and which 
from its white colour would be easily confounded with the chalk, especially at 
a time when geology was much less attended to than at present. 
* 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. 
t To surhed stone is to set it edgewise, contrary to the posture it had in the 
quarry, says Dr Plot, " Oxfordshire," p. 77. But surbeddi7ig does not succeed in 
our dry walls ; neither do we use it so in ovens, though he says it is beat for 
Teynton stoue. ^ 
