Who is THIS man?!

[Gene C]

Who is this?

His fondness for reflective pursuits soon resulted in an embarrassing incident.

"XXXXXXXXXX's favorite resort for meditation was
Lafayette Square. Here, every fair night, he could
be seen wandering under the pines, either alone,
meditating, or arm in arm with XXXXXXXXXXX,
talking over the affairs of the army.

One night, as he thus sauntered alone, the keeper
of the gates, as usual, locked the gates at ten
o'clock, but XXXXXXXX meditated and strolled on,
unconscious of time. When he came to one gate it
was locked. He hurried to the other. It was
locked also. Not a soul on the street. What was
to be done? To scream would be ridiculous. To
climb over the fence impossible. To sleep on a
bench what a position for XXXXXXXXXXXXXX!
Luckily a private of a Massachusetts regiment on
duty in came along, and was in the same
predicament. XXXXXXX let the private mount
on his back and scale the iron palings. He was
over, succeeded in waking the keeper, and
XXXXXXXXX was again free.

Who is XXXXXXX ?