But whoever it was that first invented the art of thus cutting
marble, and so multiplying the appliances of luxury, he displayed
considerable ingenuity, though to little purpose. This
The[1] sand of Æthiopia is the most highly esteemed for this purpose; for, to add to the trouble that is entailed, we have to send to Æthiopia for the purpose of preparing our marble—aye, and as far as India even; whereas in former times, the severity of the Roman manners thought it beneath them to repair thither in search of such costly things even as pearls! This Indian sand is held in the next highest degree of estimation, the Æthiopian being of a softer nature, and better adapted for dividing the stone without leaving any roughness on the surface; whereas the sand from India does not leave so smooth a face upon it. Still, however, for polishing marble, we find it recommended[2] to rub it with Indian sand calcined. The sand of Naxos has the same defect; as also that from Coptos, generally known as "Egyptian" sand.
The above were the several varieties of sand used by the
ancients in dividing marble. More recently, a sand has been
discovered that is equally approved of for this purpose; in a
certain creek of the Adriatic Sea, which is left dry at low
water only; a thing that renders it not very easy to be found.
At the present day, however, the fraudulent tendencies of our
workers in marble have emboldened them to use any kind of
river-sand for the purpose; a mischief which very few employers
rightly appreciate. For, the coarser the sand, the
wider is the division made in the stone, the greater the quantity
of material consumed, and the more extensive the labour
required for polishing the rough surface that is left; a result
of which is that the slabs lose so much more in thickness.
For giving the last polish to marble,[3] Thebaic stone[4] is considered
well adapted, as also porous stone, or pumice, powdered
fine.
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