This point of Maubeuge and of its fall must be discussed later; for the moment all we need note is that the fortress afforded for a few hours—that is, during the night of Monday to Tuesday, the 24th-25th August—support to the British line during its first halt upon the rapid and perilous retirement from Mons.

Meanwhile the whole of the French 5th Army had been falling back with equal rapidity, and upon its right the 4th Army had followed soon; and as this French retirement had preceded the retirement of the British, its general line lay farther south.

On the other hand, from the nature of the topography in this section of the Franco-Belgian border, the units of the French command had to fall back farther and more rapidly in proportion as they stretched eastward. The attack of the enemy in forces of rather more than two to one had come, as we have seen, not only from across the line of the Sambre, but, once Namur had fallen, from across the line of the Meuse at right angles to the line of the Sambre. Therefore the 5th and the 4th Armies, contained within the triangle bounded by the Sambre and Meuse, retiring from blows struck from the direction of the arrows 1-5 over all that hilly and wooded country known as the Thiérache, were, as to the extreme salient of them at A, compelled to a very rapid retirement indeed; and on this Sunday night the French line was deflected southward, not without heavy losses, until either on that night or on the Monday morning it joined up with the forces which stretched northward through and from Mézières. An attempt to counter-attack through the precipitous ravines and deep woods on to the valley of the Semois had failed, and the line as a whole ran, upon this night between the Sunday and the Monday, much as is indicated upon the accompanying sketch.

Sketch 53.

From this it will be seen that the British contingent away upon the extreme left was in very grave peril, not only because the turning movement was wholly directed round their exposed flank, but also because, their retirement having come late, they stood too far forward in the general scheme at this moment, and therefore more exposed to the enemy's blow than the rest of the line. With this it must be remembered Tournai had already fallen. It was very imperfectly held by a French Territorial brigade, accompanied by one battery of English guns; and the entering German force, in a superiority of anything you like—two, three, or four to one—easily swept away the resistance proffered in this quarter.

These German forces from Tournai had not yet, by the nightfall of Monday, come up eastward against the British, but they were on the way, and they might appear at any moment. The corps next to them, the 4th of von Kluck's five, was already operating upon that flank, and the next day, Wednesday, 26th of August, was to be the chief day of trial for this exposed British wing of the army.

So far the operations of the British Army had not differed greatly from the expected or at least one of the expected developments of the campaign.

The operative corner, if it should not have the luck, through losses or blunders on the part of the enemy, to take the counter-offensive after receiving the third shock, is intended to retire, and to draw upon itself a maximum of the enemy's efforts.

But between what had been intended as the most probable, and in any case perilous, task of this body (which comprised, it will be remembered, six French and ultimately two British army corps) turned out, within twenty-four hours of the retreat, and within forty-eight of the fall of Namur, to be an operation of a difficulty so extreme as to imperil the whole campaign, and in this operation it was the British force upon the outer left edge of the line—the unsupported extremity round which the enemy made every effort to get—which was bound to receive the severest treatment. This peculiar burden laid upon the Expeditionary Force from this country was, of course, gravely increased by the delay in beginning its retreat, which we have seen to be due to the delay in the communication to it by the French of the news of the fall of Namur. On account of this delay not only was the extreme of the line which the British held immediately threatened with outflanking, but it still lay somewhat forward of the rest of the force. It was in danger of being turned round its exposed edge C, not only because it lay on the extreme of the line, but also because, instead of occupying its normal position, AB, which it would have occupied had the retreat begun with all the rest, it actually occupied the position CD, which made it far more likely to be surrounded than if it had been a day's march farther back, as it would have been if the French Staff work had suffered no delays.