When the last vessel had alighted on the summit of the mountain it was found that out of a fleet numbering two hundred and fifty warships only a hundred and eighty remained--the rest were scattered in undistinguishable fragments along the Russian frontier. As for the amount of damage that had been done to the enemy as a set-off to this heavy loss, the Aerian commanders could form no even approximate estimate of it. All they knew was that the six frontier cities, and a score or so of smaller towns and villages, were now mere heaps of ruins, vast charnel-houses choked with unnumbered corpses. The Russian army of invasion must have been practically annihilated, and certainly its remnants would be too hopelessly demoralised by the unspeakable horrors it had survived to be of the slightest use for further fighting. As soon as the roll had been called, the fleet, in two squadrons of ninety vessels each, took the air and crossed the mountains to Gorlitz, which had been selected a year before as a convenient spot for the establishment of an arsenal and power-station, standing as it does at the angle of intersection of two great mountains which form the natural bulwarks of Bohemia. Here the stock of motive-power and the ammunition of all the vessels were renewed, and at daybreak the squadrons were just about to take the air when a telephonic message was received from Paris that a large fleet of air-ships had appeared above the city and had begun to bombard it. This message had been sent in compliance with a system of intercommunication which Alan had instituted between all the great cities of Europe, and all the power-stations and rendezvous throughout the Continent. The moment an enemy appeared over any town messages were to be sent to all the stations simultaneously, and detachments of warships were to be despatched to the threatened point as soon as the warning was received. It will be seen that this system would enable a very large force to be concentrated upon any threatened point, and, in fact, before the sun was two degrees above the horizon of Paris, eight squadrons of Federation warships, including the two under the command of Alan and Alexis, were flying at full speed from all four points of the compass towards the city which for over half a century had been the acknowledged capital of the Continent. Little more than an hour sufficed for the _Avenger_ and the _Isma_ to pass over the six hundred miles which separated Gorlitz from Paris. Flying at their utmost speed they left their squadrons to follow the two admirals, knowing that every captain could be implicitly trusted to do the work allotted to his ship without further orders. The object of Alan and Alexis was to get first to the scene of action, and to avail themselves of the superior soaring powers of their two vessels to deliver an assault upon the Moslems which they could not reply to.