As a protection from the sudden fury of the summer and winter gales, the buildings were all low, thick-walled, and provided with steel doors and window-shutters which were electrically operated and centrally controlled. These slammed shut in every occupied building. The contragravity which had been sent to support the ground-defense at the south side of the Reservation turned to meet this new threat, and everything else available, including the four heavy airtanks, lifted up. Meanwhile, guns began firing from the ground and from rooftops. There had been four aircars, ordinary passenger vehicles equipped with machine-guns on improvised mounts, and ten big lorries converted into bombers, in the attack. All the lorries, and all but one of the makeshift fighter-escort, were shot down, but not before explosive and thermoconcentrate bombs were dumped all over the place. One lorry emptied its load of thermoconcentrate-bombs on the control-building at the airport, starting a raging fire and putting the radar out of commission. A repair-shop at the ordnance-depot was set on fire, and a quantity of small-arms and machine-gun ammunition piled outside for transportation to the outer defenses blew up. An explosive bomb landed on the roof of the building between Company House and the telecast station, blowing a hole in the roof and demolishing the upper floor. And another load of thermoconcentrate, missing the power-plant, set fire to the dry grass between it and the ruins of the native-troops barracks. Before the air-attack had been broken up, the soldiers of King Firkked and their irregular supporters were swarming through the dead section of wire. They had four or five big farm-tractors, nuclear-powered but unequipped with contragravity-generators, which they were using like ground-tanks of the First Century. This attack penetrated to the middle of the Reservation before it was stopped and the attackers either killed or driven out; for the first time since daybreak, the red-and-yellow lights came on around the power-plant. As soon as the combined air and ground attack was beaten off, von Schlichten ordered all his available contragravity up, flying patrols around the Reservation and retaliatory bombing missions against Skilk, and began bombarding the city with his 90-mm guns. A number of fires broke out, and at about 0200 a huge expanding globe of orange-red flame soared up from the city. "There goes Firkked's thermoconcentrate stock," he said to Paula, who was standing beside him in front of the screen.