| Major Hooper had been detailed as inspector on the staff of the division commander, and was therefore away from the regiment. He was directed to stop at a house along the line of march (in White Plains, Virginia on 26 July 1863) to protect some ladies while the troopers were passing. He was so gallant that he delayed even after the corps had gone by, and then some of Mosby’s men came from a piece of woods near by and captured him. He had just been detailed to go to the North to bring back drafted men, and was joyfully anticipating his return to his home. He was obliged to go to Richmond instead, while Lieutenant Colonel Joslin was detailed to go after the drafted me.
Colonel Joslin was captured at Brandy Station in early December 1863. Upon arrival in Richmond, he found Major Hooper of his own regiment. Major Hooper who had been some four months a prison, had been fortunate in receiving from his relatives at home some food supplies and necessary articles of clothing, and he at once took Colonel Joslin into his mess and shared with him these luxuries so that in a couple of hours’ time he had been introduced to many and made to feel as much at home as was possible in a rebel prison.
During the winter many schemes for escape were conceived and partially carried out, but none successfully, except the digging of the famous tunnel from the cellar of the building, some fifty-nine feet under the street to an opening in a vacant lot the other side, through which one hundred and ten of the prisoners passed out in one night. (He escaped from Libby Prison with 118 other officers through a tunnel on 9 Feb 1864, returning to his regiment 28 Mar 1864. ) As this was discovered on the following day, it could not be again made use of. But a limited number, and those by luck and chance, could avail themselves of this opportunity to escape, Major Hooper being one of this number, but Colonel Joslin being forced to remain. About half of the men who escaped were captured and brought back during the next few days. (Note: Major Hooper was not recaptured.)
Major Hooper's first-person account of his escape from Libby Prison in The Overland Monthly>, Vol. 5, Sept. 1870, No. 3, entitled Twelve Days "Absence Without Leave"..