We read again and again in the Histories of the Martyrs how, after being suspended aloft, they were, among other torments, loaded with weights, of which some were of lead or iron (as we shall describe elsewhere), others again of stone. Of the latter we have evidence in sundry such, that are preserved to this day here in Rome in the Churches of the Holy Apostles, as also in those of St. Apollinaris and St. Anastasius not far from the City. They were stones of great weight, black in colour, round or oval in shape, having an iron ring imbedded in the stone, through which a rope for binding and hanging could be passed and so attached to the feet or hands of those suspended.
Another thing we would not have the reader ignorant of, that certain authorities have maintained the opinion that the aforesaid stone balls, called by Josephus (Maccabees) Orbicularia, or Round Stones, were not designed specially for purposes of inflicting torture, but for weighing. This cannot possibly be so, as is proved in the notes appended to the Roman Martyrology; for stones of this kind always had (as Isidore and Alciatus, On Weights, state) the figure of the weight inscribed on them, which these evidently have not.
These weights were entirely different from those to which debtors were condemned in Law XII. of the “Twelve Tables,” these latter being nothing more than fetters. Of them Aulus Gellius speaks, saying thus, “Bind him either with a thong, or else with fetters of not less than fifteen pounds’ weight; or if a greater weight be desired, with heavier still.”