the recent discoveries of the Cavaliere de Rossi) the paths of this
cemetery, crossing and recrossing in three, four, and five stages, are
all limited to a definite and confined area,--and this area is not
determined by the quality of the ground, but apparently by the limits of
the field overhead. There can be no other probable explanation of this
but that Christians would not extend their burial-place under land that
was not in their possession. Many other facts, as we shall see in other
connections, go to establish beyond the slightest doubt the Christian
origin and occupation of the catacombs.

Descending from the level of the ground by a flight of steps into one of
the narrow underground passages, one sees on either side, by the light
of the taper with which he is provided, range upon range of tombs cut,
as has been described, in the walls that border the pathway. Usually the
arrangement is careful, but with an indiscriminate mingling of larger
and smaller graves, as if they had been made one after another for young
and old, according as they might be brought for burial. Now and then a
system of regularity is introduced, as if the _fossor_, or digger, who
was a recognized officer of the early Church, had had the leisure for
preparing graves before they were needed. Here, there is a range of
little graves for the youngest children, so that all infants should be
laid together, then a range for older children, and then one for the
grown up. Sometimes, instead of a grave suitable for a single body, the
excavation is made deep enough into the rock to admit of two, three, or
four bodies being placed side by side,--family graves. And sometimes,
instead of the simple _loculus_, or coffin-like excavation, there is
an arch cut out of the tufa, and sunk back over the whole depth of the
grave, the outer side of which is not cut away, so that, instead of
being closed in front by a perpendicular slab of marble or by tiles, it
is covered on the top by a horizontal slab. Such a grave is called an