The armies were not near enough to each other for rifles; in truth not near enough yet to be seen.

John, even with his glasses, could only discern the gray line advancing, he could make little of its form or order or of what it was trying to do.
But a light wind was now bringing smoke from one flank where the battle was far heavier than in the center, and the concussion of the artillery at that point became so frightful that the air seemed to come in waves of the utmost violence and to beat upon the drum of the ear with the force of a hammer.

Owing to the wind John could not hear the battle on the other flank so well, but he believed that it was being fought there with equal fury and determination.
He was watching with such intentness that he did not hear the sweep of an aeroplane behind him, but he did see Lannes run to General Vaugirard's car and give him a note.
While the general read and pondered, Lannes turned toward the wheel on which John sat.

Although he tried to preserve calm, John knew that he was tremendously excited.

He had taken off his heavy glasses and his wonderful gray eyes were flashing.