"As I recall, the men of Portlock's regiment left to guard the guns at St. Charles "skedalled" at the yankee approach."
A minor point of correction here. When Arkansas Post was attacked on January 10th '63, Portlock's regiment were called on for reenforcements. Their original mission had been to support the two 8 inch Columbiad smoothbore guns emplaced at St. Charles.
These were different guns than the two 32 pd rifled guns that were used in the Mound City engagement of June 17, 1862. Those two guns had not been recovered from the White River by the Confederates. And were not recovered until they were dredged out of the White River in the 1960's by the Corp of Engineers and are now on disply in the town of St Charles today.
When the 150 men marched for Arkansas Post the 200 men left behind dismantled these two gun loaded them on a steamer and transported them to De Val's Bluff and where in the process of loading them onto flatcars to be sent to little Rock to keep them from being captured.
They had almost completed this task when the Union Ironclad Gunboat Baron De Kalb (St Louis) and another pulled into sight. They were unable to move the guns. The Union reports do not record the captured of an engine. And there is no report that there was ever an engine available. But, if there was it and its crew left at the first sight of the approaching gunboats to avoid being captured.
Having no other way of defending against these two Ironclad reportedly these men left and took shelter in the woods. The only Confederates captured at De Val's Bluff according to Union Naval reports were those in the hospital there and these were paroled.
Those 200 men are the one who did return to Camp White Sulphur where along with those that were there for various reasons, mostly those sick in the hospital of the 19th Ark. and Crawfords Batt. were organized into a "holding regiment" under Col Charles Dawson's command until those men of these commands were exchanged and returned to Arkansas to reform these regiments.
Grant however didn't want those men captured at Arkansas Post exchanged back into the Mississippi River theater of operations to oppose his plans. Hence they were exchnged at City Point, Virginia instead of the normal exchange point for Trans-Mississippi POW's at Vicksburg.
So I wouldn't slight the honor of those 200 men who stayed behind to move those guns. It would seem that they did their assigned duty until there was nothing else they could have done. So I wouldn't say that they "skeddalled" exactly.