There are other kinds of courser Sands, which are browner, and have their
particles much bigger; these, view'd with a _Microscope_, seem much courser
and more _opacous_ substances, and most of them are of some irregularly
rounded Figures; and though they seem not so _opacous_ as to the naked eye,
yet they seem very foul and cloudy, but neither do these want curiously
transparent, no more than they do regularly figur'd and well colour'd
particles, as I have often found.

There are multitudes of other kinds of Sands, which in many particulars,
plainly enough discoverable by the _Microscope_, differ both from these
last mention'd kinds of Sands, and from one another: there seeming to be as
great variety of Sands, as there is of Stones. And as amongst Stones some
are call'd precious from their excellency, so also are there Sands which
deserve the same Epithite for their beauty; for viewing a small parcel of
_East-India_ Sand (which was given me by my highly honoured friend, Mr.
_Daniel Colwall_) and, since that, another parcel, much of the same kind, I
found several of them, both very transparent like precious Stones, and
regularly figur'd like Crystal, _Cornish_ Diamants, some Rubies, &c. and
also ting'd with very lively and deep colours, like _Rubys_, _Saphyrs_,
_Emeralds_, &c. These kinds of granuls I have often found also in _English_
Sand. And 'tis easie to make such a counterfeit Sand with deeply ting'd
Glass, Enamels and Painters colours.

It were endless to describe the multitudes of Figures I have met with in
these kind of minute bodies, such as _Spherical_, _Oval_, _Pyramidal_,
_Conical_, _Prismatical_, of each of which kinds I have taken notice.

But amongst many others, I met with none more observable than this pretty
Shell (described in the _Figure_ X. of the fifth _Scheme_) which, though as