Samuel
Heintzelman was born in Pennsylvania
in 1805. He served in the Seminole War and the Mexican
War and in 1861 had reached the rank of colonel.
On the outbreak of the American Civil War
Heintzelman joined the Union Army. He
was wounded at Bull Run (July, 1861)
but recovered to join the Army of the Potomac. During the Peninsular
campaign he commanded the III Corps. In May, 1862, Heintzelman was
promoted to the rank of major general and placed in command of the
Military District of Washington.
After the war Heintzelman remained in the army until retiring in 1869.
Samuel Heintzelman died in 1880.

(1)
In his autobiography Oliver
Howard
described fighting at Bull Run on 21st
July, 1861.
I
saw Burnside's men, who had come back from the field with their muskets
gleaming in the sunshine. They had some appearance of formation and
were resting on their arms. I noticed other troops more scattered;
ambulances in long columns leaving the field with the wounded. There
were men with broken arms; faces with bandages stained with blood;
bodies pierced; many were walking or limping to the rear; meanwhile
shells were shrieking and breaking in the heated air. I was sorry,
indeed, that those left of my men had to pass that ordeal.
When forming, I so stationed myself, mounted, that the men, marching
in twos, should pass me. I closely observed them. They were pale and
thoughtful. Many looked up into my face and smiled. As soon as it
was ready the first line swept up the slope, through a sprinkling
of trees, out into an open space on high ground. An enemy's battery
toward our front and some musketry shots with no enemy plainly in
sight caused the first annoyance. Soon another battery off to our
right coming into position increased the danger. And, worse than the
batteries, showers of musket balls from the wood, two hundred yards
away.
Many officers labored to keep their men together, but I saw could
effect nothing under fire. At last I ordered all to fall back to the
valley and reform behind the thicket. Before many minutes, however,
it was evident that a panic had seized all the troops within sight.
Some experienced veteran officers, like Heintzelman, entreated and
commanded their subordinates, by turns, to rally their men; but nothing
could stop the drift and eddies of the masses that were faster and
faster flowing toward the rear.
Captain Heath, of the Third Maine, who, promoted subsequently to lieutenant
colonel and fell in the battle of Gaines Mills, walked for some time
by my horse and shed tears as he talked to me: "My men will not
stay together, Colonel, they will not obey me," he said. Other
brave officers pleaded and threatened. Surgeons staying back pointed
to their wounded and cried: "for God's sake, stop; don't leave
us!" Nothing could at that time reach and influence the fleeing
crowds except panicky cries like: "The enemy is upon us! We shall
be taken!" These cries gave increase to confusion and speed to
flight.
Heintzelman, with his wounded arm in a sling, rode up and down and
made a last effort to restore order. He sharply reprimanded every
officer he encountered. He swore at me. From time to time I renewed
my attempts. My brother, C. H. Howard, if he saw me relax for a moment,
sang out: "Oh, do try again!" Part of the Fourteenth New
York from Brooklyn rallied north of Bull Run and were moving on in
fine shape. "See them," said my brother; "let us try
to form like that!" So we were trying, gathering a few, but in
vain. Then I stopped all efforts, but sent out this message and kept
repeating it to every Maine and Vermont man within reach: "To
the old camp at Centreville. Rally at the Centreville camp."

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