Twice means comes quickly.

Three times means come--danger!" In one corner of the cabin was a platform of poles, covered with straw.
I threw the sleeping-bag on this, and was soon stretched out.
Misgivings as to my strength worried me before I closed my eyes.

Once on my back, I felt I could not rise; my chest was sore; my cough deep and rasping.

It seemed I had scarcely closed my eyes when Jones's impatient voice recalled me from sweet oblivion.
"Frank, Frank, it's daylight.

Jim--boys!" he called.
I tumbled out in a gray, wan twilight.