Down below, slightly to his rear, there flashed through the fog a short
series of vari-colored lights, which to Blaine's active mind spelled
forth:

"Boches 'bout to get me. Big drive on hand. Yonder they go -- watch
out!"

That was all, but it was enough. Blaine knew that it must come from
another of the raiding scouts who had somehow gone down in
No-Man's-Land. It might come from a shell hole. Anyway, it was being
sent up by some one risking almost certain death in order to let the
Allies know that big things were already under way.

"Where are the Boche planes?" Blaine had more than once asked himself.
The balloons were gone. The few enemy planes left to guard the
gasbags had been put to flight by the daring raiders. Blaine himself
had sent one down in flames. Others had followed the retreating
raiders. Now that a night drive was on, other planes would be
converging towards the salient thus suddenly selected for a night
assault. In another instant Blaine's mind was made up.

"Here's at you, my friend," he said to himself. "I'll try to find out
who and what you are. Damn the risk!"

With the thought he turned the nose of the triplane downward, so that
it was almost at a perpendicular angle. Before this he had noted that
around the point whence had risen that telltale signal there seemed to
be a foggy void. This meant to Lafe that, for the present at least,
there was nothing doing at this particular spot. Of course those