A layer of ashes and charcoal on the top of the vault showed that the house above had perished by fire.

The vault itself was perfectly intact, the cement being as good as when first applied.

It had a door, but this we could not force, and found entrance by removing one of the flagstones which formed the roof.

The air which came up was stagnant but pure, dry and not cold.

Descending with a lantern, I found myself in an apartment fitted up as a bedroom in the style of the nineteenth century.