Let us look again at the sixty-mile stretch of country from Arras to the North Sea, the great danger zone during the month of October and for many months afterwards. An enemy advancing from Belgium and North France, desirous of capturing the coast of the Channel, and making himself master of the Strait of Dover, must cross this stretch of country in order to attain his object. You already know that a most determined effort was made by the Germans to push through the gap at Arras, from which the railways give access not only to the Channel ports but to Paris. As you are aware, General Maud'huy was able to say to the Germans, "No road this way." Seventeen miles north of Arras we find the second passage by which the Channel ports may be reached by an army advancing westwards. You have already heard more than once of the town of La Bassée, which stands on the canal uniting Béthune with Lille. A great thrust through La Bassée would serve almost as well as a thrust through the Arras gap, for Béthune, which lies seven miles to the west, is the junction of two diverging railways, both of which lead to Boulogne. The more northerly of these lines has a branch which runs through the important railway centre of Hazebrouck[39] to Ypres. At Hazebrouck the St. Omer[40]-Ypres line meets the railway which comes westwards from Lille through Armentières to the coast. A little west of Hazebrouck this line subdivides: one route goes through St. Omer to Boulogne; the other runs north to Dunkirk, from which Calais and Boulogne may be reached by a line along the coast. Examine this little railway map carefully, and you will see that if the Germans could make a thrust through the Allied lines at La Bassée they would soon be in possession of the two railway junctions of Béthune and Hazebrouck, which would give them no fewer than four lines of railway for their advance on the sea-coast. Had the Germans broken through at this point, the Allied forces to the north would have been overwhelmed. We shall soon learn that the sally-port at La Bassée was the scene of long and desperate struggles. [Illustration] The third passage by which the enemy might capture the coast of North France and outflank the Allies at the same time is by way of the Yser Canal and the Ypres Canal. You have already learnt how Rawlinson's army tried to block the road to Ypres and how the Belgians withdrew to the line of the Yser in order to contest its passage. Rawlinson's force was far too small to resist the numbers which were hurled against it on and after the 18th of October, and the much-battered Belgians were far too exhausted to offer more than a feeble resistance to the forces of the enemy following hard on their heels. They were strengthened by some French Territorials, but even with this support they had to fall back behind the line of the Yser on the 16th. [Illustration: Weary Belgian Soldiers resting on the Banks of the Yser River after their Retreat from Antwerp.