If we ever have a war here or any sort of invasion, it is just such places that may be dangerous.

Even in my own case it is much too near the Castle to be neglected.
The indications were meagre--only where a fire had been on a little shelf of rock; and it was not possible, through the results of burning vegetation or scorched grass, to tell how long before the fire had been alight.

I could only guess.

Perhaps the mountaineers might be able to tell or even to guess better than I could.

But I am not so sure of this.
I am a mountaineer myself, and with larger and more varied experience than any of them.