The engineer organization for the march to Savannah was as follows:

First. Engineer troops and troops of the line on engineer duty: (1) First Regiment Michigan Engineers and Mechanics, Colonel J. B. Yates, unassigned, receiving orders direct from headquarters Military Division of the Mississippi, ten companies, 1,500 men. (2) First Missouri Engineers, Lieutenant Colonel William Tweeddale, in charge of pontoon train with Right Wing (Army of the Tennessee), five companies, 500 men. (3) Fifty-eighth Regiment Indiana Volunteer Infantry, Colonel George P. Buell, in charge of pontoon train of Left Wing, ten companies, 775 men. Total, 2,775 men.

Second. Pioneers: Left Wing, six divisions, each having a pioneer corps of the average strength of 100 men, 600 men; Right Wing, seven divisions, each having a pioneer corps of the average strength of 100 whites and 70 negroes, 1,200 men; total, 1,800 men.

Recapitulation: Engineer troops and troops of the line doing engineer duty, 2,775 men; pioneers, 1,800 men; aggregate for engineer duty, 4,575 men.

Third. Tools and tool trains: Each of the pioneer corps carried a sufficient number of tools to work their full strength, and in the Right Wing they were supplied with a duplicate set, which were carried in wagons. In the Left Wing each brigade was provided with a tool wagon, loaded with about 350 intrenching tools. A great many axes and shovels were in the hands of the troops, but always within reach in case of emergency. The Michigan Engineers and Mechanics had a train of fifty wagons, of which twenty were loaded with tools, as follows: 1,500 axes and halves, 1,500 shovels, 700 picks and halves, 200 hatchets, and an ample supply of carpenters' and bridge building tools, and extra saws and augers; also, 100 hooks which I had devised for twisting railroad iron. The remainder of the wagons carried subsistence and quartermaster's stores. The Missouri Engineers had a much smaller train, which was somewhat mixed up with pontoon train of which they had charge. They carried the following intrenching tools: 500 shovels, 500 axes; also, an assortment of carpenters' and black-smiths' tools.

Fourth. Pontoon trains: Left Wing-pontoniers, Fifty-eighth Regiment Indiana Volunteer Infantry, Colonel George P. Buell commanding, 775 men. Materials: 51 canvas pontoon-boats, complete, 15 extra covers, 10 anchors, 2,000 pounds rope, 37 horses, 505 mules, 94 wagons, 3 ambulances, 2 tool wagons, 3 forces, 850 chesses, 196 balks, and the necessary harness, &c., to make the outfit complete. This regiment carried its own supplies of subsistence and forage on the wagons in the above list. The length of bridge which could be built from this train by cutting small timber for the balk was 850 feet. Right Wing-pontoniers, First Missouri Engineers, Lieutenant Colonel William Tweeddale commanding; strength, 530 men. Materials: 28 canvas pontoon-boats complete, 28 boat wagons, 600 chesses, 15 chess-wagons, 196 claw balks, 1 force, 1 battery wagon, 2 tool wagons (a general assortment), 7 forage wagons, and a sufficient quantity of harness, rope, &c. Length bridge, 580 feet; total length of bridges, 1,430 feet.

The foregoing was the engineer organization and equipment which was considered sufficient to make the campaign which I knew would be made to Savannah.

On the 7th of November I received a telegram from General Sherman directing me to take charge of the destruction of the railroads, depots, steam machinery, &c., in the city of Atlanta. On the 9th I telegraphed as follows: "I am all ready to do the work