Some of the inscriptions preserve a record of the occupation or trade of the dead, sometimes in words, more often by the representation of the implements of labor.  Here, for instance, is one which seems like the advertisement of a surviving partner:—­

  DE BIANOBA
  POLLECLA QVE ORDEV BENDET DE
  BIANOBA

  From New Street.  Pollecla, who sold barley
  on New Street.

Others often bear a figure which refers to the name of the deceased, an armoirie parlante as it were, which might be read by those too ignorant to read the letters on the stone.  Thus, a lion is scratched on the grave of a man named Leo; a little pig on the grave of the little child Porcella, who had lived not quite four years; on the tomb of Dracontius is a dragon; and by the side of the following charming inscription is found the figure of a ship:—­

  NABIRA IN PACE ANIMA DULCIS
  QVI BIXIT ANOS XVI M V
  ANIMA MELEIEA
  TITVLV FACTV
  APARENTES SIGNVM NABE

Navira in peace.  Sweet soul, who lived sixteen years, five months.  Soul honey-sweet.  This inscription made by her parents.  The sign a ship.

The figures that are most frequent upon the sepulchral slabs are, however, not such as bear relation to a name or profession, but the commonly adopted symbols of the faith, similar in design and character to those exhibited in the paintings of the catacombs.  The Good Shepherd is thus often rudely represented; the figure of Jonah is naturally, from its reference to the Resurrection, also frequently found; and the figure of a man or woman with arms outstretched, in the attitude of prayer, occurs on many of the sepulchral slabs.  The anchor, the palm, the crown, and the dove, as being simpler in character and more easily represented, are still more frequently found.  The varying use of symbols at different periods has been one of the means which have assisted in determining approximate dates for the inscriptions upon which they are met with.  It is a matter of importance, in many instances, to fix a date to an inscription.  Historical and theological controversies hang on such trifles.  Most of the early gravestones bear no date; and it was not till the fourth century, that, with many other changes, the custom of carving a date upon them became general.  The century to which an inscription belongs may generally be determined with some confidence, either by the style of expression and the nature of the language, or by the engraved character, or some other external indications.  Among these latter are the symbols.  It has, for instance, been recently satisfactorily proved by the Cavaliere de Rossi that the use of the emblem of the fish in the catacombs extended only to the fourth century, so that the monuments upon which it is found may, with scarcely an exception, be referred to the preceding period.  As this emblem went out of use, owing perhaps to the fact that the Christians were no longer forced to seek concealment