, employed by Hadrian
in his villa, and which appears to have been brought from Terni, where
it still exists in abundance. From the quarry near Volterra the
Etruscans obtained the alabaster for their cinerary urns. The European
alabasters are accumulated masses of stalactite and stalagmite, formed
by the slow dropping of water charged with sulphate of lime, to which
circumstance they owe the parallel stripes or concentric circles with
which they are marked, while the rich and delicate varieties of
colouring are produced by the oxides of iron which the water carries
with it in its infiltration through the intervening strata. They are
very soft and perishable, and consequently are very rarely found among
the ruins of ancient Rome. The Oriental alabasters, on the other hand,
which are distinguished from the European by their superior hardness
and durability, are in reality not sulphates, but carbonates of lime.
Their hardness is quite equal to that of the best statuary marbles.
The ancient quarries on the hill--the modern Mount St. Anthony--near
the town of Alabastron, in Middle Egypt, from which the material got
its name, have only recently been re-opened, but blocks of large size
and perfect beauty have been obtained. Owing to the facility with
which alabaster can be reduced by fire to lime, very few large
examples of it in Rome have escaped the ruthless kilns of the middle
ages. The most interesting specimens of ancient alabaster are the very
beautiful vase of Alabastro cotognino, prolate in form, and in colour
white, streaked with very light pink, which contained the ashes of
Augustus, found in the ruins of his mausoleum, and now in the Vatican;
the bust of Julius Caesar, made of the variety _tartaruga_, from the
resemblance of its brownish-yellow markings to tortoise-shell, in the
Museum of the Capitol; and the two large blocks of _alabastro a
pecorella_, brought from the Villa of Hadrian, in the fourth portico
of the Vatican, the largest and most beautiful specimens of this very
rare alabaster in Rome, distinguished by white circular blotches, like
a flock of sheep huddled together, on a deep blood-red ground. In the
churches there are numerous specimens of all the varieties, forming
the columns and sheathings of altars, memorial chapels, and monuments;
the incrustations of alabaster on the walls of the Borghese chapel, in
Santa Maria Maggiore, being conspicuous for their splendid effect. The
baldacchino above the hig