354 
Mr. Webster on the Reygate Stone . 
rather than by actual knowledge, and as this arrangement has been 
quoted and followed by several persons who have since published 
elementary books on geology, and descriptions of the English strata, 
it appeared incumbent on me to bring to a test the accuracy of my 
statement. 
Two circumstances were chiefly attended to in the subsequent 
examination : 
1st. The nature of the constituents of the bed in question, and 
of the subordinate beds which it contained. 
2dly. The relative place of these beds, and also of those above 
and below them, with which they are connected. 
The soft Reygate stone is essentially composed of fine grains of 
siliceous sand and of mica, cemented by earthy carbonate of lime, 
and it contains also a small quantity of dark green particles usually 
called green earth : this latter substance is not so abundant as is 
generally the case in the green sand formation, a glass being neces- 
sary to observe it, but it is never totally wanting. 
The earthy state in which the carbonate of lime exists occasions 
the stone to have little durability when exposed to the weather i 
accordingly, although it has been much employed in ancient build- 
ings, (particularly where carving was used,) it is a bad material, as 
may be seen from its state of decay. When fresh quarried it is 
extremely soft ; and it is the practice to keep it in the dry for several 
months, by which it acquires some hardness ; a neglect of this pre- 
caution has sometimes occasioned its speedy decomposition. Its use 
is now restricted to filling in walls, and to the construction of hearths 
and covings for fire places, a purpose for which it is extremely well 
adapted, being easily worked, and resisting better than any of our 
stones, the heat of the fire. 
The town of Reygate stands upon the ferruginous sand, a bed 
