put in their proper positions, tools were placed
conveniently, and, soon after the crossing was made, the men commenced
to work.

In raising these intrenchments, drilling and organizing, the army passed
about a month--varied only by alarms two or three times a week at night
that the rebels were coming, whereupon the troops turned out and stood
in line till daylight. It was shrewdly suspected that these alarms were
purposely propagated from headquarters to accustom the men to form
themselves quickly at night without panic. In after times, in front of
Richmond, we had such duty to perform, without any factitious reasons.
It was a matter of necessary precaution to stand to our arms nightly for
two or three hours before daybreak.

Until just previous to the disastrous Bull Run campaign, no higher
organization than that of brigades was adopted; but a day or two before
the march commenced, General McDowell organized the brigades into
divisions. These were reorganized by General McClellan as the two and
three years volunteers joined the army. The organization of corps was
made in the spring of 1862, just before the commencement of the
Peninsula campaign, and is now the organization of the army.

The complete organization is now as follows:

_Regiments_, generally of ten companies.
_Brigades_, of four or more regiments.
_Divisions_, generally of three brigades.
_Corps_, generally of three divisions.

The various staffs have gradually been organized, until they now stand
(in the Army of the Potomac) as follows:

At the headquarters of the army:

_A Chief of Staff._
_An Assistant Adjutant-General._
_A Chief Quartermaster._
_A Chief Commissary._
_A Chief of Artillery._
_An Assistant Inspector-General._
_A Medical Director._
_A Judge Advocate-General._
_An Ordnance Officer._
_A Provost Marshal-General._
_A Chief Engineer._
_A Signal Officer._
_Aides-de-Camp._

The rank of these officers, as the staff is now composed, is as follows:
The chief of staff, a major-general; the assistant adjutant-general,
chief of artillery, and provost marshal, brigadier-generals; assistant
inspector-general, a colonel; medical director, chief engineer, judge
advocate-general, majors; the signal officer, chief commissary, and
ordnance officer, captains; the aides, of various ranks, lieutenants,
captains, and majors. Most of these officers do not derive their rank
from their position on the staff, but