9. Cox asked Thomas Jones to help the fugitives across the river
Thomas Jones was a Confederate sympathizer and sometimes spy for the Confederacy. Throughout the war years, he aided the Confederate cause by moving infiltrators, spies, smugglers, and contraband across the Potomac in both directions. His knowledge of the river, and of the underground network of southern supporters in Maryland made him the logical person for Cox to contact. Jones agreed to help, but was aware that he was being watched closely by the Union troops hunting Booth and Herold. He directed them to wait until he contacted them, and to be ready to move when he did. Why he delayed several days is unknown, but the announcement of the large reward for Booth’s capture seemed to compel him to move.
The amount of money offered for Booth and Herold was large enough to cause all but the most loyal Confederate sympathizers to change their mind, a fact no doubt considered by Stanton when he authorized the reward. Capturing Booth would reveal the identities of those who had helped him, leading to their arrests as well. On the night of April 21 (some say April 20) Jones went to the thicket in which the fugitives were hidden and provided them with directions to a small boat he had hidden in the river. They were to cross the Potomac and make contact with a colleague of Jones’s once they were on the Virginia side. Booth and Herold, neither of them experienced with boats, made their way to the banks of the Potomac.