Upon our return from the battle field to Pleasant Valley, we heard that orders to McClellan to advance had come from Washington. The only answers to inquiries when the advance would take place, were ominous shakings of the head or shrugs of the shoulders, which were indicative of anything but belief in a speedy movement. We also heard of the appointment of General Burnside to the command of three army corps, the precursor of a greater command yet to come. We have in our new commander-in-chief a general who has an implicit belief that our cause is just, and a trust in Providence that he will make the just cause victorious. In General McClellan we had also a general who believed in Providence, and who has always shown great reverence in his writings. General McClellan is reticent. You can, however, tell somewhat of the opinion of the head of the house from his children; and judging from the tone of belief among the General's military family, from that long delay after Antietam, it was pretty evident that in his opinion the South cannot be subdued, and that the question between us was a matter of boundary. With General Burnside we have no such belief. His faults, if they are faults, are those of the bold general, not of the Fabian order. At Newbern he brought at once into the fight every soldier he had, not keeping one in reserve; and he gained the battle by his audacious policy. And it is the wonder to this day of every one who has been over the battle field, that the enemy should have been beaten. With all this boldness, he is a modest man; twice before having refused the chief command: once when it was offered to him at the time Pope was appointed; again when McClellan took it before Washington. Of a commanding figure, every inch a soldier, one cannot look upon him and his kindly eye without instant admiration. His modest way of riding among the men, alone or attended by a single orderly, will make him beloved by our republican soldiers. He was so then, and 'Old Burn,' as they familiarly called him, was everywhere heartily received. By the way, McClellan's nickname on the Peninsula was 'George,' and not 'Little Mac,' as is generally supposed. General Burnside, we believe, is a good judge of men. The generals he selected for his North Carolina expedition, though previously unknown, and but captains in the service, have already distinguished themselves and justified his choice. General Foster, now commanding the department of North Carolina, has shown himself an able, active general. All who have been connected with him, speak highly of him. Though not a Massachusetts man, he has a peculiar penchant for Massachusetts troops: he was first at Annapolis, and picked out for the first brigade the Massachusetts soldiers. Recently, through the Governor, he has obtained some eight or ten more regiments, and in some way or other he has the crack ones.