We've got to shoot under there so fast that they won't have a chance to find out too much about us.

The headlight will help us, too.
It ought to dazzle them so that they won't be able to see into the car at all.

As soon as we're close to them, I'm going to sound the bugle pretty steadily." They rushed on toward the culvert faster and faster.

The powerful headlight illuminated the scene before them, and they could see a dozen or more dark figures.

And as they came closer, they saw that several men were looking at them, trying to shade their eyes with their hands.
Fred sounded the bugle steadily now, and saw that this seemed to relieve the watchers.