The order of the Tsar was obeyed in part only, for by the time that the word to recommence the bombardment had been flashed round the circuit of the entrenchments, more than half the batteries had been put out of action. The twelve air-ships stationed at equal intervals round the vast ellipse, and discharging their No. 3 shell from their four guns ahead and astern, from an elevation of four thousand feet, had simultaneously wrecked half the batteries of the besiegers before their occupants had any clear idea of what was really happening. Wherever one of those shells fell and exploded, earth and stone and iron melted into dust under the terrific force of the exploding gases, and the air-ships, moving with a velocity compared with which the utmost speed of the aerostats was as a snail's pace, flitted hither and thither wherever a battery got into action, and destroyed it before the second round had been fired. There were still twenty-five aerostats at the command of the Tsar which had not been sent against the relieving forces, and as soon as it was realised that the aërial bombardment of the batteries came from the air-ships of the Terrorist fleet, they were sent into the air to engage them at all hazards. They outnumbered them two to one, but there was no comparison between the manœuvring powers of the two aërial squadrons. As soon as the aerostats rose into the air, the Terrorist fleet receded northward and southward from the batteries. Their guns had a six-mile range, and it did not matter to them which side of the assailed area they lay. They could still hurl their explosives with the same deadly precision on the appointed mark. But with the aerostats it was a very different matter. They could only drop their shells vertically, and where they were not exactly above the object of attack their shells exploded with comparative harmlessness. As a natural consequence they had to follow the air-ships, not only away from London, but over their own encampments, in order to bring them to anything like close quarters. The aerostats possessed one advantage, and one only, over the air-ships. They were able to rise to a much greater height. But this advantage the air-ships very soon turned into a disadvantage by reason of their immensely superior speed and ease of handling. They darted about at such a speed over the heads of the massed forces of the League on either side of London, that it was impossible to drop shells upon them without running the inevitable risk of missing the small and swiftly-moving air-ship, and so causing the shell to burst amidst friends instead of foes. Thus the Terrorist fleet, sweeping hither and thither, in wide and ever changing curves, lured the most dangerous assailants of the beleaguered city farther and farther away from the real scene of action, at the very time when they were most urgently needed to support the attacking forces which at that moment were being poured into London.