Beyond the moat, a glacis sloped down to another ditch.
The cannon were placed in casemates.

Some of them had been withdrawn, the casemates fitted with massive shutters, and converted into prisons for the use of officers.

Two captains were lodged in the same casemate with Fergus.

No light came from without, but there was a low semicircular window over the door.
This was very strongly barred, but admitted sufficient light, in the daytime.
"Not such bad quarters," Fergus said, as he looked round.

"When the cold weather comes, we shall only have to stuff straw through those bars, leaving one square open for light, and manage to hang a thick curtain across it at night.