-officer reported that by
studying the enemy's signals he had learned the key, and that he
could read their signals. He explained to me that he had
translated a signal about noon, from Pine Mountain to Marietta,
"Send an ambulance for General Polk's body;" and later in the day
another, "Why don't you send an ambulance for General Polk?" From
this we inferred that General Polk had been killed, but how or
where we knew not; and this inference was confirmed later in the
same day by the report of some prisoners who had been captured.

On the 15th we advanced our general lines, intending to attack at
any weak point discovered between Kenesaw and Pine Mountain; but
Pine Mountain was found to be abandoned, and Johnston had
contracted his front somewhat, on a direct line, connecting Kenesaw
with Lost Mountain. Thomas and Schofield thereby gained about two
miles of most difficult, country, and McPherson's left lapped well
around the north end of Kenesaw. We captured a good many
prisoners, among them a whole infantry regiment, the Fourteenth
Alabama, three hundred and twenty strong.

On the 16th the general movement was continued, when Lost Mountain
was abandoned by the enemy. Our right naturally swung round, so as
to threaten the railroad below Marietta, but Johnston had still
further contracted and strengthened his lines, covering Marietta
and all the roads below.

On the 17th and 18th the rain again fell in torrents, making army
movements impossible, but we devoted the time to strengthening our
positions, more especially the left and centre, with a view
gradually to draw from the left to add to the right; and we had to
hold our lines on the left extremely strong, to guard against a
sally from Kenesaw against our depot at Big Shanty. Garrard's
division of cavalry was kept busy on our left, McPherson had
gradually extended to his right, enabling Thomas to do the same
still farther; but the enemy's position was so very strong, and
everywhere it was covered by intrenchments, that we found it as
dangerous to assault as a permanent fort. We in like manner
covered our lines of battle by similar works, and even our
skirmishers learned to cover their bodies by the simplest and best
forms of defensive works, such as rails or logs, piled in the form
of a simple lunette, covered on the outside with earth thrown up at
night.

The enemy and ourselves used the same form of rifle-trench, varied
according to the nature of the gro