Here are just two days of entries in the work log of the Peninsular Campaign*
May 19 and 20.—Laid corduroy and graded about 150 feet of road near the first crossing of the
turnpike road and the railroad after leaving White House; also built four small bridges and laid
corduroy at various points on the road along which General Franklin's command passed from the
crossing of Black Creek to a point half a mile beyond the blacksmith's shop; in all, about 1,000
feet of road corduroyed, and much ditching and grading. Finding the road crossing the valley
about a mile and a half beyond the last point mentioned (about half a mile beyond the White
Church) impassable at midnight, built two bridges across streams about 8 feet wide and 5 feet
deep; used in each nine or ten stringers, of from 10 to 15 inches in diameter, laid on crib
abutments; also laid corduroy over about 800 feet of road in manner as follows:
Longitudinal stringers were first laid over these sticks averaging 7 inches in (diameter, the
interstices again filled with smaller sticks, and the whole covered with brush and dirt. A large
portion of the force was kept constantly employed in ditching and grading, and the work thus
performed was not less valuable than that before described.
May 20 - Corduroyed 1,000 feet of road about 1 mile west of Black Creek. The same afternoon took up
and rebuilt bridge over Mill Creek at the grist-mill. Two spans 18 and 20 feet; roadway, 12 feet;
four pine stringers, 9 inches; covering, 2-inch oak plank.
* Taken from my work on the Army of the Potomac Engineers