SHOWING HOW THE GENERAL OF THE MACKEREL BRIGADE ISSUED AN AFFECTING GENERAL ORDER; EXEMPLIFYING THE BEAUTIES OF A SPADE-CAMPAIGN AS EXHIBITED IN STRATEGY HALL, AND CELEBRATING A NOTABLE CASE OF NAVAL STRATEGY. WASHINGTON, D. C., July 26th, 1862. The high-minded and chivalrous Confederacy having refused to consider itself worsted in our recent great strategic victory near Paris, my boy, it only remained for the General of the Mackerel Brigade to commence undermining the Confederacy, after the manner of a civil engineer; and when last I visited the lines, I found a select assortment of Mackerels engaged in the balmy summer pastime of digging holes, and dying natural deaths in them. There was one chap with an illuminated nose, who attracted my particular attention by landing a spade-full of sacred soil very neatly in my bosom, and says I to him: "Well, my gallant sexton, how do the obsequies progress?" "Beautiful," says he, pausing long enough to take a powder which the surgeon had left with him. "We've just struck a large vein of typhoid fever, and them air Peninsula veterans, which, you see in them holes yonder, are already delirious with it. Really," says the chap, with an air of quiet enjoyment, as he climbed into the hospital litter, just sent after him--"really, there's a smart chance of pushing on our cemetery to Richmond before the roads become impassable again." I was looking after him, as the bearers carried him off, my boy, when I saw Captain Villiam Brown ambling leisurely toward me on his geometrical steed, Euclid, alternately perusing a paper which he held in his right hand, and discussing a canteen in his left. The countenance of the warrior was thoughtful, and his shovel swung listlessly against the charger's flank. "How now, my Jack of Spades?" says I, sportively. "Ah!" says Villiam, slowly descending from the roof of his stallion, and suffering the latter to lean against a tree, "here is a new Proclamation for the moral refreshment of the United States of America. Read this impartial edick," says Villiam impressively, "and you will find it worthy of the Union Track Society." I took the official parchment, my boy, and found inscribed upon it the following affecting GENERAL ORDER.