The Seed of Empire by Fred M. White

It was an annoying incident, one of those little things that happen in war, and for a second or two the Musketeers hung back before the deadly concentration of that fire. Another minute, and they might have been wiped out altogether, for the experience of the war shows that one machine gun well served may hold a whole brigade, as indeed has happened more than once in the present campaign. There was not a man amongst the Musketeers who failed to recognise the fine work those two German officers were doing. But even the finest feeling of chivalry has to give way at moments such as these.

"We shall have to shoot them," Bentley murmured. "Can't they see that it is quite hopeless? Why, good Lord, they're all by themselves!"