Elements of Military Art and Science / Or, Course Of Instruction In Strategy, Fortification, Tactics Of Battles, &C.; Embracing The Duties Of Staff, Infantry, Cavalry, Artillery, And Engineers; Adapted To The Use Of Volunteers And Militia; Third Edition; With Critical Notes On The Mexican And Crimean Wars.

by H. W. Halleck

But the march of the English cavalry under Lord Lake, before the battle of Furruckabad, is, if we can trust the English accounts, still more extraordinary than any thing recorded of the Romans or the French—it is said that he marched seventy miles in twenty-four hours!!!

As a general rule, troops marching for many days in succession will move at the rate of from fifteen to twenty miles per day. In forced marches, or in pursuit of a flying enemy, they will average from twenty to twenty-five miles per day. And for only two or three days in succession, with favorable roads, thirty miles per day may be calculated on. Marches beyond this are unusual, and, when they do occur, are the result of extraordinary circumstances.

Convoy.—A convoy consists of provisions, military munitions, &c., sent from one point to another, under the charge of a detachment of troops, called an escort. When regular dépôts and magazines are established, with proper relations to the line of operations, convoys requiring particular escorts are seldom necessary, because the position of the army will cover the space over which the magazines are to be moved. But in the immediate vicinity of the enemy, or in a country whose inhabitants are hostile or insurrectionary, precautions of this kind should always be resorted to.

The size and composition of the escort must depend upon the nature of the country and the imminence of the danger. The ground to be passed over should be previously reconnoitred, and the line of march be taken up only after the most satisfactory reports. When once put in motion, the convoy should be thoroughly hemmed in by flankers, to give warning to the escort of the approach of the enemy. Small parties of cavalry are detached on all sides, but particularly in advance. The main body of the escort is concentrated on the most exposed point of the convoy while the other sides are guarded by subdivisions. In case of an attack by a large party, the baggage wagons may be formed into a kind of defensive field-work, which, with one or two pieces of light artillery, can in this way resist a pretty strong effort to destroy or carry away the convoy.

As a general rule, it is better to supply the wants of an army by small successive convoys than by periodical and large ones. Even should some of the former be captured their loss would not be materially felt; but a large periodical convoy offers so great a temptation to the enterprise of the enemy, and is so difficult to escort, that he will venture much to destroy it, and its loss may frustrate our plans of a siege or of an important military operation. If the Prussian army, when besieging Olmutz, had observed this rule, the capture of a convoy would not have forced them to raise the siege and to retreat.

Napoleon estimates that an army of 100,000 men in position will require the daily arrival of from four to five hundred wagon loads of provisions.

The difficulty of moving provisions, baggage, &c., in a retreat, is always very great, and the very best generals have frequently failed on this point. Indeed, the best concerted measures will sometimes fail, amid the confusion and disorder consequent upon a retreat with an able and active enemy in pursuit. In such a case, the loss of the provision-trains in a sterile or unfriendly country may lead to the most terrible disasters. We will allude to two examples of this kind: the retreat of the English from Spain in 1809, and that of the French from Russia in 1812.

When Sir John Moore saw that a retreat had become necessary to save his army from entire destruction, he directed all the baggage and stores to be taken to the rear, and every possible arrangement to be made for their preservation and for the regular supplies of the army. But the want of discipline in his troops, and more especially the want of a proper engineer organization to prepare the requisite means for facilitating his own marches, and impeding the enemy's pursuit, prevented his plans from being fully carried into execution. Much suffering and great losses were consequently inflicted upon his troops; a large portion of his baggage and military stores was captured, and even the treasure of his army, amounting to some 200,000 dollars, was abandoned through the ignorance and carelessness of the escorting officer.

In Napoleon's march into Russia, his plans had been so admirably combined, that from Mentz to Moscow not a single estafette or convoy, it is said, was carried off in this campaign; nor was there a day passed without his receiving intelligence from France. When the retreat was begun, (after the burning of Moscow,) he had six lines of magazines in his rear; the 1st, at Smolensk, ten days' march from Moscow; those of the 2d line at Minsk and Wilna, eight marches from Smolensk; those of the 3d line at Kowno, Grodno, and Bialystok; those of the 4th line at Elbing, Marienwerder, Thorn, Plock, Modlin, and Warsaw; those of the 5th line at Dantzic, Bamberg, and Posen; those of the 6th line at Stettin, Custrin, and Glogau. When the army left Moscow it carried with it provisions sufficient for twenty days, and an abundance of ammunition, each piece of artillery being supplied with three hundred and fifty rounds; but the premature cold weather destroyed thirty thousand horses in less than three days, thus leaving the trains without the means of transportation or suitable escorts for their protection: the horrible sufferings of the returning army now surpassed all description.

The officer selected to escort convoys should be a man of great prudence, activity, and energy, for frequently very much depends upon the safe and timely arrival of the provisions and military stores which he may have in charge.