As it stood on August 25 the situation was that the Belgians held all the country to the north of the Scheldt and the Dyle, and the Germans all the country to the south of these rivers. From Turcoing on the French frontier to Antwerp, the Scheldt follows a course roughly parallel to the coast. At Antwerp its bed describes a sharp bend to seaward. Some ten miles south of this bend, the main waterway receives the Rupel, formed by the junction to the eastward of the Dyle and the Nethe. Taken together, the Scheldt and the Dyle, both deep, sluggish watercourses, offer a natural defence of the seaboard provinces. From behind this natural line of defence the Belgians, ceaselessly on the watch, sallied forth at every chance offered, to harass and entrap the enemy. Sudden dashes were made upon his communications by armed motor-cars; attacks were made upon railway lines and bridges; his convoys were unexpectedly attacked and cut up by superior forces; in a word, he was kept in perpetual hot water. The military effect of this was more important than may at first sight appear. In the first place, it was made necessary for the Germans, not only to keep heavy forces afoot in Belgium, but to disperse those forces. Hence though the forces, taken together, were large, the Belgians concentrated on Antwerp were in a position to deliver in superior strength a blow at any one of these bodies, and thus to worst the whole of them in detail. In the second place, these Parthian tactics made the transport of munitions and supplies to the German armies in France by the line through Brussels a business calling for vigilance and caution. That greatly lessened the value of the line to the enemy. On this supply line the German right wing in France mainly depended. The Belgians, therefore, were not merely defending their own country, but indirectly were aiding the French and British operations on the farther side of the French frontier. Now the weakness of the Belgian position was that, while they could hold the line of the Dyle and that of the Scheldt as far as Termonde, their force was too small to bar the passage of the Scheldt farther west. It was open to the Germans, by seizing Ghent, to turn the defensive position in a manner that would speedily have become dangerous. Well aware of this, the Germans advanced upon Ghent. Coincidently, however, the Belgian operations farther east became more active and threatening. To meet them, the Germans were obliged to withdraw most of the troops sent to Ghent. Just at that juncture (August 27) a body of British marines was landed at Ostend. From Ghent the enemy had hastily to withdraw. British troops advanced to Ghent, and the whole line of the Scheldt was secured.