fortress of Verdun the actual battlefield contained no feature, the capture or retention of which would have vitally affected the battle, but it was of a very diversified nature. The western strip is, generally speaking, a large cultivated plain, in which the Marne, flowing through a well-marked valley, receives as tributaries the Ourcq and the two Morins. Like the parent river, the tributaries are slow-moving and unfordable, but well provided with stone bridges and lined with woods and country houses. This sector of the battlefield is fairly open; but an exception must be made of the forests of Villers-Cotterets and Compiegne, where the paths are intricate and blind, and where a force losing direction might find itself in serious difficulties if attacked. East of this sector is a strip bounded generally by N. and S. lines through Soissons and Reims, and roughly bisected by the course of the river Marne. Generally speaking, the terrain here is a plateau cut by the well-marked river valley and marked by copses and plantations which increase in size and frequency towards the east. The eastern edge of the plateau, running from the Montagne de Reims to the Aisne, and thence to Laon and beyond, forms the line of heights known as Les Falaises de Champagne. A tactical feature of some importance is the marshland near Sezanne called Les Marais de Saint Gond, formed by a pocket of clay and extending for about 10-12 m. from E. to W., and 1-2 m. broad. The marshes have been to a large extent reclaimed, and between the acres of grassland the streams which unite to form the Petit Morin run in deep ditches. In fine weather the ground is fairly dry, but in heavy rains the slopes N. and S. drain down to the pocket, the canalized streams overflow, and the clay soil becomes one vast quagmire. Some narrow causeways have been constructed, but these can be brought under artillery fire, particularly from a round-topped hill at Mondement, which is a valuable tactical feature; and since the causeways are neither engineered nor metalled they are all likely in flood time to become as deep in mud as the adjoining marshes. Passing eastward, the third strip of the battlefield is the wide plain of Champagne Pouilleuse. Here are long undulating ridges covered with heath and crowned on top with small fir plantations, moorlands with patches of cultivation, and two large permanent training camps N. and S. of Chalons, the whole forming a fine arena for a conventional battle of the three arms.
East of this immense plain the woods become more frequent and dense, meriting in many cases the larger designation of forests. Chief among these is the Forest of Argonne, a long, densely wooded low ridge running almost N. and S., traversed only by a few paths and by two gaps, through which run two high roads and the St. Menehould-Verdun railway. Between the ridge and the valley of the Meuse lies an upland country, chiefly of pasture-land intersected by numerous narrow ravines; and on the right bank of the Meuse are the abrupt Hauts-de-Meuse (or C6tes de la Meuse), looking down on the plain of the Woevre. In this sector of the battlefield is situated the fortress of Verdun, which, although it formed a very sharp salient in the French line, yet by its projection served the useful purpose of dividing the Crown Prince's army into two parts. Unlike Namur and Liege, the fortress had been kept in readiness to resist a sudden attack and contained an adequate garrison, including mobile troops distinct from the field armies. Further, the forts of the perimeter had been supplemented by a network of trenches and outworks pushed well out, which greatly minimized the chance of the fortress being quickly crushed by a concentrated storm of heavy artillery fire. In spite of the great use which the Germans made of mechanical transport, the retention of Verdun in French hands was a serious handicap to the invaders, for it prevented their making use of the main line of railway running thence to Germany; and the difficulty of communication was aggravated by the fact that when the battle began Maubeuge was still untaken and the main line of railway from Cologne through Liege and Namur was in consequence blocked. Practically the only line of rail available to supply the 1¼ to 1½ million Germans deployed along the general line of the Marne was that which ran N. from Reims to Mezieres and thence by the valley of the Meuse to Dinant and Namur. In lateral communications, however, the Germans were admirably served, the Meaux-Reims-Verdun and Meaux-Chalons-Verdun railways affording them the means of transferring troops from one portion of the battlefield to another at will. The suddenness and impetuosity of the Allies' attack, however, was to render the advantage a theoretical rather than an actual benefit.
The new "limited envelopment" scheme of the German General Staff held the field for just four days; and, to carry it out, Supreme Headquarters sent out orders on Sept. 3 to the effect that the I. Army was to follow in echelon behind the II. and to be responsible for the protection of the right flank of the whole German front. But at the moment when the orders were issued the situation was far different from that envisaged by Supreme Headquarters. So far from being echeloned behind the II. Army, Gen. von Kluck's columns were hurrying over the Marne, with the II. Army more than a day's march behind upon the Aisne. It has been suggested that Gen. von Kluck was fired by the recollection of Prince Frederick Charles at Mars-la-Tour, in which battle the former had served as a young officer of artillery. Be this as it may, in spite of the orders issued he continued his advance, and Supreme Headquarters quickly came to the conclusion that even the limited envelopment, which had been substituted for the original plan, must be curtailed.
It was during the evening of Sept. 4 that the new directive was brought to the I. Army. The essential point in it was the announcement that the attempt to force the whole French army back in a south-easterly direction, towards the Swiss frontier, was no longer practicable. Intelligence had reached the Germans about movements of French troops westward from Toul and Belfort, which pointed to a concentration on the French left; and further, there was an ominous reference to a collection of troops in the neighbourhood of Paris to threaten the right flank of the German I. Army. How far the initiative had passed from the Germans is revealed by a study of these orders of the evening of Sept. 4. The whole German plan broke down, and the invaders had to reshape their scheme to cope with that of Gen. Joffre. The I. and II. Armies were now to face E. towards Paris, the former between the Oise and the Marne and the latter between the Marne and the Seine; on the left the IV. and V. Armies by a determined advance S.E. were to open a passage across the Moselle for the VI. and VII. Armies, in which region a pianissimo Sedan might still take place, although Supreme Headquarters cautiously stated that "success could not yet be foreseen." The III. Army in the centre was to push S. ready to help either wing as required. Thus Gen. von Moltke was forced to throw to the winds the hopes founded on the great massive wheel of five armies pivoting on Thionville, and, instead, was compelled hurriedly to assign to his armies three divergent axes of march towards the W., S., and S.E.
Gen. von Kluck's contribution towards solving the difficult problem with which Supreme Headquarters were confronted was to disregard his orders. Instead of remaining between the Oise and the Marne he continued to push on over the latter river, increasing at every step his lead over the II. Army, behind which he should have been following. As the French VI. Army had orders to be in a position of readiness N.E. of Paris so as to be able to cross the Ourcq between Lizy and May-en-Multien in the general direction of Chateau-Thierry, early collision between it and the flank guard of the German I. Army was now but a matter of hours. Gen. Joffre had ordered that the offensive was to be begun by the VI., British, and V. Armies on the morning of Sept. 6, but as a matter of fact the battle was brought on earlier by the preliminary movements of the VI. Army.
In view of the forthcoming offensive the French VI. Army, during Sept: 5, began to fill in to its right so as to deploy generally on the line St. Mesmes-Foret d'Ermonville facing north-east. Opposite the right wing of this position and commanding all the neighbouring terrain runs a well-marked ridge which, starting from the high ground of Dammartin, is prolonged towards the S.E. by the hill at Montge, and thence by a succession of isolated knolls, of which the more pronounced are those of Monthyon