They had thrown away their weapons and were running for home with eyes distended and nothing in mind but to put distance between there and the enemy.

I jumped out of the car and seized one man.
"What are you running from?
What has happened ?" I demanded, holding him harder the more he struggled.
"Poison gas!" he gasped, and I let him go.
I thought I caught a whiff of the darned stuff then, but that may have been imagination.
"Poison gas!" I said, returning to the car, and Rene made a fine exhibition of himself, smothering his head under the foxlined overcoat and screaming.
He got right down on the floor of the car and lay there huddled and gasping--which may have been a sensible precaution; I don't know.
There was no time just then to bother with him.
The flukey morning breeze shifted several points.

The mist curled suddenly and began to flow diagonally across our line of cars instead of toward us, and from one moment to the next you could see straight along the road for maybe a mile or more.

There was a sight worth seeing-- Feisul's cavalry in full rout--running away from ghosts by the look of it--their formation hardly yet broken, horse and man racing with the wind and a scattering of unhorsed fugitives streaming behind like a comet's tail.
According to Grim, who should know, that cavalry division was the kingpin of Feisul's plan.

He had intended to lead a raid in person, swooping down the French flank to their rear; but the three staff traitors, Daulch, Hattin and Aubck, sent forward the previous evening to place the division and hold it ready, had simply tipped the French off to the whole plan and at the critical moment of Feisul's arrival on the scene had ordered the sauve-qui-peut.