"One drops asleep after dinner, and then wakes up ready to go for any length of time.

It's being a good comrade to the poor fellow," I thought; and, picking up his rifle, I took over his duty just as if it were my own, keeping my eyes wandering over the dark grey stones in front, and sweeping the whole space.

Then my breath suddenly felt as if checked in my surprise, for about thirty yards away, as near as I could guess, there was a dark shadow passing one of the great blocks.
"Fancy," I said to myself as soon as I could recover from my surprise; and, treating myself as I had treated my fellow-trooper, I mentally declared I had thought about it till I seemed to see it.
"It's all imagination," I said again; and then I lowered the rifle I held, a thrill running through me as I distinctly saw the dark shadow again, but nearer than before.

This time I was certain it was not imagination.

A figure--enemy or no--was cautiously stealing towards our lines! My first impulse was to fire at the figure and give the alarm; but on second thoughts I hesitated to go to such an extreme.