In advancing from the Chattahoochee, the arrangements Sherman made for the supply of his army provided separate lines for the trains of the three columns. McPherson' s wagons would reach him from Marietta by way of Roswell and the bridge which General Dodge built there. Schofield's had their depot at Smyrna and came by the wooden bridge which we built at the mouth of Soap Creek to replace the pontoons. The latter were of canvas, and whilst unequalled for field use, were unfit for a bridge of any permanence, because the canvas would be destroyed by long continuance in the water. As soon as they could be replaced by a pier or trestle-bridge of timber, they were taken up, cleaned and dried, and then packed on their special wagons for transport. This train was in charge of a permanent detachment of troops who became experts in the handling and care of the material and in laying the bridge. The brigade of dismounted cavalry in my division was left at the river as a guard for the wooden bridge which was kept up till the railway bridge was built and opened for use. [Footnote: Official Records, vol. xxxviii. pt. v. p. 163.] Thomas's troops, who were more than half the army, drew their supplies from Vining's Station byway of bridges at Power's Ferry (mouth of Rottenwood Creek) and Pace's Ferry, a mile below. Grant sent warning of rumors afloat that reinforcements would be sent Johnston from the east, and in advancing from the Chattahoochee by a great wheel to the right, Sherman extended his left so that McPherson should move to the east of Decatur and break the Georgia Railroad there, whilst Garrard with his division of cavalry should continue the destruction toward Stone Mountain and make the gap as wide as possible. [Footnote: _Id_., p. 158.] This movement made the distance travelled by McPherson and Schofield a long one, and extended their front largely, whilst Thomas was much more compact. But when once the railway should be so broken that Johnston's direct communication with the east would be interrupted, McPherson and Schofield would both move toward their right, and in closing in upon Atlanta, come into close touch with Thomas. [Footnote: _Id_., p. 167.]