OF CORNWALL. 73 
from thofe ftrata. Hence the hands at Ch’andour creek, near Pen- 
zance, and thence to Marazion, are of a pale-blue colour, like the 
rocks at Ch’andour, and the fhingle on the ftrand ; and on the 
illands of Scilly, it is a bright-coloured fhining hand, made for the 
moft part of the talc and cryftals of that granite, commonly called 
Moorftone, which edges all thefe illands ; and the fame may be faid 
of moft other parts of Cornwall, where we have hands, reddifh, 
yellow, bright and blue, according as ftones of each particular hue 
prevail in the lands adjoining. This factitious fand is fo like the na- 
tural, that it is extremely difficult to diftinguilh them one from an- 
other ; and it is very likely, that they may have been fo mixed at 
the time of the Deluge, that the factitious is often taken for the 
natural at land, and the natural as erroneoufly reckoned among the 
factitious on the banks of rivers, and on the fhores of the fea. 
In fands there is no uniformity of fhape : every fort conftfts of 
particular fands of various fhapes; fome round, fome angular, 
home nodulous ; nay, what is more extraordinary, the fea-fand, 
which may be faid to be in perpetual motion, has, notwithftanding 
this, innumerable little angular points, as if it had never been 
in the fea at all ; and the fands about London, and in Northampton- 
fhire, Oxfordftiire, and the midland counties, have abundance of 
particles almoft globular, which would make one believe, that they 
had buffered the agitation of the fea. Having compared a fmall kind 
of moorftone fand, found among the white clay of Amalebreh u , 
three miles from any fea, with the fea-fand of Scilly, I rather 
thought the land- fand more angular than that of the fea, and it 
felt rougher ; but the difference in the microfcope was inconfidera- 
ble ; fo that the difference in fhape, betwixt fands of the fame fize, 
is not decifive or charaCteriftic : the truth is, the fmaller the fand, 
the more it efcapes the trituration of the waters, and the purer and 
harder the cryftal is of which the parts are compofed, the lefs is the 
attrition, and vice verfa. Upon viewing the larger fort of Amale- 
breh fands, I find them full of little angular proceffes forming gritts, 
which do not appear to have undergone any diminution ; but upon 
viewing the larger fea-fands, their extremities are all obtufe, plainly 
manifefting, that they have been rounded by the force of waters. 
As to the oval and globular fands, found at land, whatever caufe it 
was that formed flints and pebbles into a round or nodulous figure 
(which, in the chapter of the formation of ftones, we fhall more 
properly enquire into) formed alfo the fame figure of thofe fands 
which we find at a great diftance from the fea and rivers. 
SECT. 
Shap 
* Mentioned before, page 63. 
u 
But 
