tive Aztec type of the human head issuing from
the mouth of an animal. (_See cut_, p. 101.) Beyond this there is in
the stone blade the curious fact of a people which had attained to so
complex a design and such an elaborate ornamentation remaining in the
Stone-age; and, somewhat curiously, the locality of that stone blade is
fixed, by its being of that semi-transparent opalescent calcedony which
Humboldt describes as occurring in the volcanic districts of
Mexico--the concretionary silex of the trachytic lavas.

The second Mask is yet more distinctive. The incrustation of
turquoise-mosaic is placed on the forehead, face, and jaws of a human
skull, the back part of which has been cut away to allow of its being
hung, by the leather thongs which still remain, over the face of an
idol, as was the custom in Mexico thus to mask their gods on
state-occasions. The mosaic of turquoise is interrupted by three broad
transverse bands, on the forehead, face, and chin, of a mosaic of
obsidian, similarly cut (but in larger pieces) and highly polished,--a
very unusual treatment of this difficult and intractable material, the
use of which in any artistic way appears to have been confined to the
Aztecs (with the exception, perhaps, of the Egyptians).

The eye-balls are nodules of iron-pyrites, cut hemispherically and
highly polished, and are surrounded by circles of hard white shell,
similar to that forming the teeth of the wooden mask.

The Aztecs made their mirrors of iron-pyrites polished, and are the
only people who are known to have put this material to ornamental use.

The mixture of art, civilization, and barbarism which the hideous
aspect of this green and black skull-mask presents accords with the
condition of Mexico at the time of the Conquest, under which human
sacrifices on a gigantic scale were coincident with much refinement in
arts and manners.

The European history of these three specimens is somewhat curious. With
the exception of two in the Museum at Copenhagen, obtained many years
ago by Professor Thomsen from a convent in Rome, and, though greatly
dilapidated, presenting some traces of the game kind of ornamentation,
they are believed to be unique.

The Wooden Mask and the Knife were long known in a collection at
Florence. Thirty years ago the mask was brought into England from that
city, as Egyptian: and, somewhat later, the knife was obtained from
Venice.

Subsequently the Skull-mask, with a wig of hair said