or is covered to some extent by a thin, dry, reddish crust adhering to it. This crust or film is all that is left of the blood the vase originally contained. Vials, or ampullæ, in the interior of the tombs are of course perfectly preserved. It is indeed interesting to look on one of them, and to mark exactly the line to which the liquid blood once reached, and the purple hue of the sediment or crust now left, with its brighter or darker shades of color, perhaps from the character of the blood, more probably from the thickness or thinness of the crust itself. Under all the accumulated evidence, one scarcely needs to read the rude inscription found and still legible, although only scratched in the mortar when it was soft: SANGUIS, or SANG: SATURNINI, _The blood of Saturninus_. We know that this is blood which once flowed from a martyr’s veins, in testimony of his faith in Christ our Lord. In the 17th century, when Bosio, Boldetti, and others brought out such vases from the catacombs, and special attention was directed to them, the nature of this dry reddish crust adhering to the interior was examined chemically. There was no discordance in the results obtained. Among those who made such an examination was the celebrated Leibnitz, a Protestant, among the ablest and most learned men of that age. He gives an account of his process, and the decision at which he arrived: _This coloring matter on the glass is sanguineous_. Some years ago, the present Pontiff, Pius IX., had a new analysis made according to the fullest and most accurate tests of modern chemistry. The answer was still the same: This substance is, so far as chemistry can decide, precisely what ought to remain as the residuum of human blood. It is clear that, both as to the custom of the early Christians of carefully gathering up the blood of their martyrs, of placing it in ampullæ, or vases, and religiously preserving it, and likewise as to the identification of the ampullæ themselves, the testimony is all that can be desired. Bosio, Aringhi, Boldetti, Mamachi, Gaume, Marchi, Raoul-Rochette, De Rossi, Perret--all who have studied the question, are unanimous in recognizing these numerous old Roman vials, or ampullæ, still found in the catacombs and tombs or preserved in the churches, as the identical vials, or ampullæ, so used by the ancient Christians. On this point, there remains not the slightest room for doubt.