The next morning saw the resumption of the advance toward the Weldon Railroad. A Union patrol succeeded in reaching the tracks on the 23d and promptly started the work of destruction. Alarmed by the threat to this important supply line, the Confederates launched a sharp attack that forced the withdrawal of the Union forces from the vicinity of the railroad. However, the Union lines confronting Petersburg had been extended across the Jerusalem Plank Road, thus cutting off its use to the city. In itself, the Battle of Jerusalem Plank Road on June 22-24 was not too important militarily. The North could quickly replace the loss of 2,300 men. The Weldon Railroad, although its days were numbered, was still able to deliver supplies to Petersburg. But as an indication of Grant’s tactics, it pointed the course of the campaign ahead. It marked the first of several attempts to encircle Petersburg, and the others to follow would not all be as disappointing to Northern hopes. In these repeated drives to the west lay the essence of the basic plan to capture Petersburg. On July 9, the plan of operations decided upon by the Union high command was revealed in an order from Meade’s headquarters giving detailed instructions for the building of fortifications and the development of siege tactics. It thus became apparent that the Union plan was to reduce Petersburg by a process of attrition—a process that was to last for 9 months. There were still those in the attacking forces, however, who felt that, with a little imagination, the city could be taken by direct assault. While most of the troops were digging siege lines, another smaller group had already begun work on a unique plan which would, if successful, make further encirclement unnecessary. [Illustration: _The Federal cavalry saw little battle action during the siege, but it did its share in destroying Lee’s lines of communication. Combat artist Alfred R. Waud of Harper’s Weekly made this sketch of Brig. Gen. James H. Wilson’s troopers tearing up part of the Weldon Railroad, south of Petersburg, during their June 1864 raid._] [Illustration: _The “Dictator,” also called “The Petersburg Express,” was a 17,000-pound, 13-inch Federal seacoast mortar mounted on a reinforced railroad car. During the early part of the siege, this huge weapon fired 200-pound explosive shells into Petersburg, 2½ miles away, from a curved section of the Petersburg and City Point Railroad. On July 30, 1864, it was part of the artillery support for Union troops during the Battle of the Crater._] [Illustration: _The men who commanded the “Dictator”—Col. H. L. Abbot (the man on the left in front) and officers of the 1st Connecticut Heavy Artillery. Next to Abbot is Maj. Gen. Henry J. Hunt, in charge of all artillery operations on the Petersburg front._]