Smith was ordered to move about the 1st of February.
While Sherman was waiting at Vicksburg for the arrival of Hurlbut with his surplus men, he sent out scouts to ascertain the position and strength of the enemy and to bring back all the information they could gather.

When these scouts returned it was through them that he got the information of General Polk's being at Meridian, and of the strength and disposition of his command.
Forrest had about 4,000 cavalry with him, composed of thoroughly well-disciplined men, who under so able a leader were very effective.
Smith's command was nearly double that of Forrest, but not equal, man to man, for the lack of a successful experience such as Forrest's men had had.

The fact is, troops who have fought a few battles and won, and followed up their victories, improve upon what they were before to an extent that can hardly be counted by percentage.

The difference in result is often decisive victory instead of inglorious defeat.

This same difference, too, is often due to the way troops are officered, and for the particular kind of warfare which Forrest had carried on neither army could present a more effective officer than he was.
Sherman got off on the 3d of February and moved out on his expedition, meeting with no opposition whatever until he crossed the Big Black, and with no great deal of opposition after that until he reached Jackson, Mississippi.