Natas had formed an entirely accurate estimate of the policy of the leaders of the League when he told Tremayne, in the library at Alanmere, that they would concentrate all their efforts on the reduction of London. The rest of the kingdom had been for the present entirely ignored. London was the heart of the British Empire and of the English-speaking world, for the matter of that, and therefore it had been determined to strike one deadly blow at the vital centre of the whole huge organism. That paralysed, the rest must fall to pieces of necessity. The fleet was destroyed, and every soldier that Britain could put into the field had been mustered for the defence of London. Therefore the fall of London meant the conquest of Britain. After the battles of Dover and Harwich the invading forces advanced upon London in the following order: The Army of the South had landed at Deal, Dover, and Folkestone in three divisions, and after a series of terrific conflicts had fought its way _viâ_ Chatham, Maidstone, and Tunbridge to the banks of the Thames, and occupied all the commanding positions from Shooter's Hill to Richmond. These three forces were composed entirely of French and Italian army corps, and numbered from first to last nearly four million men. On the north the invading force was almost wholly Russian, and was under the command of the Tzar in person, in whom the supreme command of the armies of the League had by common consent been now vested. A constant service of transports, plying day and night between Antwerp and Harwich, had placed at his disposal a force about equal to that of the Army of the South, although he had lost over seven hundred thousand men before he was able to occupy the line of heights from Hornsey to Hampstead, with flanking positions at Brondesbury and Harlesden to the west, and at Tottenham, Stratford, and Barking to the east. By the 29th of November all the railways were in the hands of the invaders. A chain of war-balloons between Barking and Shooter's Hill closed the Thames. The forts at Tilbury had been destroyed by an aërial bombardment. A flotilla of submarine torpedo-vessels had blown up the defences of the estuary of the Thames and Medway, and led to the fall of Sheerness and Chatham, and had then been docked at Sheerness, there being no further present use for them. The other half of the squadron, supported by a few battleships and cruisers which had survived the battle of Dover, had proceeded to Portsmouth, destroyed the booms and submarine defences, while a detachment of aerostats shelled the land defences, and then in a moment of wanton revenge had blown up the venerable hulk of the _Victory_, which had gone down at her moorings with her flag still flying as it had done a hundred years before at the fight of Trafalgar. After this inglorious achievement they had been laid up in dock to wait for their next opportunity of destruction, should it ever occur.