The battle of Resaca began near the southern part of the battlefield on 7 May. On the previous day, Col. J.W. Sprague's Brigade of Brig. Gen. Dodge's XVI Corps secured Shipp's Gap in Taylor's Ridge, allowing the Army of the Tennessee to enter Snake Creek Gap. On 9 May, Major Gen. McPherson ordered Dodge to advance toward Resaca, about 8 miles to the east. Reinforced by the 66th Illinois, Birge's Western Sharpshooters, the Federal line drove Confederate forces back toward the town for some 7 miles, bringing the lightly defended railroad into view, but McPherson then ordered Dodge back to the gap. During the next rainy days, marching and skirmishing continued along Rocky Face Ridge while Johnston moved troops to Resaca and reinforced positions there. On 13 May, Dodge and Logan's XV Corps established their line near the Lafayette-Resaca Road west of Camp Creek, about a mile from Resaca, with the Oostanaula River in view, while the rest of Sherman's forces remained to the north. Across Camp Creek, about halfway to Resaca, Leonidas Polk's Corps, including Scott's Brigade of Loring's Division and a two-gun battery, held an advanced skirmish line. At about 1:00 p.m., supported by artillery, Wood's Brigade countered the attack, and the 66th Illinois, armed with Henry 16-shot repeating rifles, again took part. After several hours of heavy fighting, Scott's Brigade retired across Camp Creek and rejoined Polk's line. Heavy fighting resumed at about 5:00 p.m. on 14 May, when, encouraged by Logan's XV Corps on the hills to the rear, Wood's and Smith's brigades led an advance across the creek and low ground, using a small bridge and fallen logs, and captured the entrenchments, forcing the Confederates back toward Resaca. Polk then reformed west of the railroad on the outskirts of the town, and although Johnston ordered him to retake the hills, three Confederate assaults continuing until about 10:00 p.m. failed. Logan's losses exceeded 600 men killed, wounded, or missing.