The chips are still bright and the earth fresh turned, in the foreground where are the Confederate earthworks such at General Joseph E. Johnston had caused to be thrown up by the Negro laborers all along his line of possible retreat. McPherson, sent by Sherman to strike the railroad in Johnston's rear, got his head of column through Snake Creek Gap on May 9th, and drove off a Confederate cavalry brigade which retreated toward Dalton, bringing to Johnston the first news that a heavy force of Federals was already in his rear. McPherson, within a mile and a half of Resaca, could have walked into the town with his twenty-three thousand men, but concluded that the Confederate entrenchments were too strongly held to assault. When Sherman arrived he found that Johnston, having the shorter route, was there ahead of him with his entire army strongly posted. On May 15th, "without attempting to assault the fortified works," says Sherman, "we pressed at all points, and the sound of cannon and musketry rose all day to the dignity of a battle." Its havoc is seen in the shattered trees and torn ground in the lower picture. [Illustration: THE WORK OF THE FIRING AT RESACA COPYRIGHT, 1911, REVIEW OF REVIEWS CO.] [Illustration: ANOTHER RETROGRADE MOVEMENT OVER THE ETOWAH BRIDGE COPYRIGHT, 1911, REVIEW OF REVIEWS CO.] The strong works in the pictures, commanding the railroad bridge over the Etowah River, were the fourth fortified position to be abandoned by Johnston within a month. Pursued by Thomas from Resaca, he had made a brief stand at Kingston and then fallen back steadily and in superb order into Cassville. There he issued an address to his army announcing his purpose to retreat no more but to accept battle. His troops were all drawn up in preparation for a struggle, but that night at supper with Generals Hood and Polk he was convinced by them that the ground occupied by their troops was untenable, being enfiladed by the Federal artillery. Johnston, therefore, gave up his purpose of battle, and on the night of May 20th put the Etowah River between himself and Sherman and retreated to Allatoona Pass, shown in the lower picture. [Illustration: ALLATOONA PASS IN THE DISTANCE]