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ÍÁ×ÉUÌ.
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195
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hood, Naxos, with the smallest expenditure of labour, and in any quantity required.
The
process known to the most barbarous tribes of primeval times, that of
drilling holes through stones by the long-continued turning of a stick,
constantly supplied with sharp sand and water, upon the same point, has
left us many memorials in the Celtic axe and hammer-heads, where the
shape of the widely-splayed helve-holes plainly indicates the agents
brought into play. These are abundant in regions which do not produce
Emery ; but sharp sand, aided by the unlimited expenditure of time,
effects the same result.*
The
Assyrian gem-engravor soon perceived the advantage to be derived from
an instrument that could hollow out his figures in hemispherical
indentations, exactly formed to the size required, in addition to the
simple straight cuts which alone he could produce by the original
method of filing with the fractured Emery. The perforations traversing
the length of all these cylinders prove that already, as soon as they
were invented as signets, the principle of the drill was well known.
These holes are bored so truly that we discover not merely that they
were done with a metal wire, instead of a stick, charged with Emery and
oil, but that this wire must have been turned by means of a bow, in
order to work thus evenly, and not to run the risk of splitting the
cylinder. It could not have been long before
*
The Mexicans had no iron, the New Zoalanders no metal whatever, yet the
former cut the Amazon-stone, the latter the Jade, both amongst the
hardest stones known to the lapidary, into the most elaborate and
highly-finished monsters. La Chaux mentions a very instructive case of
a return to a soft medium for the application of the cutting par-iieles
amidst the most elaborate appliances of the art : Guay gave the
finishing touches to his chef-d'œuvre the bust of Louis XV. in cameo, by working the diamond-powder with tho point of a quill into lines otherwise inaccessible. Intagli also are polished internally by means of a leaden point similarly charged.
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