596 
APPENDIX. 
[c.- 
Where a large surface is covered with a calcareous sand, 
that becomes agglutinated into a stone, which he con- 
siders as analogous to the rocks of Guadaloupe; and of 
which the specimens that I have seen, resemble those pre- 
sented by Captain Beaufort to the Geological Society, from 
the shore at Rhodes. — Dr. Paris ascribes this concretion, 
not to the agency of the sea, nor to an excess of carbonic 
acid, but to the solution of carbonate of lime itself in 
water, and subsequent percolation through calcareous sand; 
the great hardness of the stone arising from the very 
sparing solubility of this carbonate, and the consequently 
very gradual formation of the deposit- — Dr. Mac Culloch 
describes calcareous concretions, found in banks of sand 
in Perthshire, which “ present a great variety of stalactitic 
forms, generally more or less complicated, and often ex- 
ceedingly intricate and strange*',” and which appear to 
be analogous to those of King George’s Sound and Sweer’s 
Island : — And he mentions, as not unfrequently occurring in 
sand, in different parts of England, (the sand above the 
fossile bones of Norfolk is given as an example,) long 
cylinders or tubes, composed of sand agglutinated by car- 
bonate of lime, or ‘ calcareous stalactites entangling sand,’ 
which, like the concretions of Madeira, and those taken for 
corals at Bald-Head, “ have been ranked improperly, with 
organic remains.” 
The stone which forms the fragments in the breccia of 
New Holland, is very nearly the same with that of the 
cement by which they are united ; — the difference consisting 
only in the greater proportion of sand which the fragments 
contain; — and it would seem, that after the consolidation of 
* “ On an arenaceo-calcareous substance,” &c.^ — Quarterly Jour- 
nal, (Royal Institution), Oct. 1823, vol. xvi. p. 79-83, 
