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parts where these felspathic groups occur in the centre of a rocky mass, a cavity 
or rude basin is formed by their crumbling away. In fact, in some instances I 
have removed handsfulof the loose felspar from rock-basins in course of formation. 
When the felspar superabounds at the side of a rocky mass, its decomposition 
merely forms an inequality or indent more or less deep, which never attracts atten- 
tion. When the felspar is more abundant on the under surface of a projecting 
mass which is exposed to the weather, a rock-basin is formed by the same process, 
but no water can lodge in the cavity, and unless the Druids possessed the mira- 
culous power of making basins and pitchers hold water with their mouths down- 
wards, such inverted basins would have been of no use to them in collecting the 
dew and rain for the ablutions and purifications prescribed by their religion. It 
has also been conjectured that rock-basins were not only made for preserving 
lustral water, but for containing the blood of victims used as sacrifices. These 
are pure speculations, unsupported by a single fact. That the Druids used them 
for purposes of superstition is highly probable, but even this is mere conjecture. 
Then as for the two kinds of rock-basins, one with channels of communication 
between the several cavities on the same stone, and the other with a single cavity 
only, the explanation already offered equally applies to them all, and there can be 
little doubt that the Arch-Druid Time, aided by the atmosphere, is the grand exca- 
vator of all rock-basins past, present, and to come. The fact that these cavities are 
frequently found near rocking stones in no way strengthens the supposition that 
the Druids formed them to contain their libations, because the same natural cause 
which produced one, gave rise to the other. 
The sketch of the celebrated rock-basin at Carnbre, Cornwall, and known as 
the Carnbre Quoit, as well as the smaller one I saw at Treryn, will convey no idea 
of either being a work of art. Even men with stone implements could have made 
better shaped basins than these rudely formed depressions. The Carnbre Quoit 
has been figured in some antiquarian publications. 
Besides the Cornish rock-basins, others occur amongst the Bradley rocks in 
Derbyshire, at Dartmoor, Devonshire, and some other localities. These rude 
basins may occur in other rocks than granite, but they were probably produced in 
a similar manner — by the unequal weathering of the stone, or by the surging 
waters on the sea shore, or the eddying currents of a river. 
The author then minutely described a visit to the Rocking stone of 
St. Levan, 70 tons in weight, which could be set in motion by one 
man, and which had once been displaced and set up again by Lieut. 
Goldsmith many years previously. 
Rocking stones in Cornwall are called logan rocks, from u log," a provincial 
term, " to rock, or vibrate." Logan rocks, like rock-basins, are produced by 
natural causes incessantly in operation — by the gradual decomposition of the two 
surfaces of compound masses in juxtaposition with each other, which are composed 
of ingredients of unequal durability, and which arc separated by natural joints 
