The Catacombs are an obscure Argument. I have seen those of _Rome_, I have seen those of _Naples_, and as they say there are Catacombs in the Neighbourhood of all the great Towns of that part of _Italy_, I had been glad to have seen them where-ever they are. They are an obscure argument indeed; but perhaps the greatest obscurity about them is, that a Matter that has so much exercis'd the Pens of the Moderns, shou'd be totally neglected by the Ancients: Neither the name nor the thing is found in the latter, whereas among the former, Antiquaries and Travellers are full of them. All they into whose way they come, think they do nothing if they do not exhaust them before they leave them; they take all their dimensions, and measure their height, their breadth and their length; they survey all the little Rooms, search every hole and corner, Criticize nicely on the quality, and calculate the Age of the poor Painting and Inscriptions, and make excursions into other Arguments, to find out the end for which they were made. The Catacombs are a narrow Gallery dug and carried a vast way under Ground, with an infinite number of others going off it on all hands, and an infinite number of little Rooms going off the Principal, and them too. Those commonly shew'd Strangers are those of _San Sebastiano_, those of _San Lorenzo_, those of _San Agnese_, and the others in the Fields a little off of _Sant Agnese_. They take their Names from the Churches in their Neighbourhood, and seem to divide the circumference of the City without the Walls between them, extending their Galleries every where under, and a vast way from it, so that all the Ground under, and for many Miles about it, is said to be hollow. Now there are two sorts of Authors that run into extravagance on this subject; the one will have them made by the Primitive Christians, adding, that in the times of Persecution they liv'd, held their Assemblies, and laid up the Bodies of their Martyrs and Confessors in them. This is the Account that prevails at _Rome_, and consequent to it there are Men kept constantly at Work in them. As soon as these Labourers discover a Repository, with any of the marks of a Saint about it, Intimation is given to the Cardinal Treasurer, who immediately sends Men of Probity and Reputation to the place, where they find a Palm painted or ingraven, or the Cypher XP, which is commonly read _pro Christo_, or a small round projection in the side of the Gallery, a little below the Repository; what is within it is carried to the Palace. Many of these Projections we have seen open, with pieces of the Vials in them; the Glass indeed was tinctur'd, and 'tis pretended that in these Vials was conserved the Blood of the Martyrs, which was thus laid up nigh their Bodies, towards the Head, to distinguish them from those of the others that were not called to the Honour of laying down their Lives for the Faith of the Gospel. After the Labourers have survey'd a Gallery, they do up the