"There are six motor rooms, three on each side," observed the baronet. "I’m taking twelve motor-mechanics to be on the safe side. When we are running free, one man will look after two engines, but in any case half the number will be off-duty at a time. Now, this is your cabin." He opened a sliding-door on the port side, corresponding with the officers’ dining-room on the starboard side. It was a compartment 20 feet by 6 feet 6 inches, with a bunk at each end running athwartships, and as plainly furnished as the owner’s quarters. "Heaps of room," declared Bramsdean, "and warming apparatus, too." "Yes," replied Fosterdyke, "we had the exhausts led under the cabins. Nothing like keeping warm at high altitudes. Warmth and good food--that’s more than half the battle. See this ladder?" He indicated a metal ladder in the alley-way, clamped vertically to the outer wall of the cabin. "Leads through that hatchway," he continued, "right to the upper surface of the envelope. There’s an observation platform--useful to take stellar observations and all that sort of thing. But you won’t find a machine-gun there," he added with a laugh. Passing between the ’midship pair of motor-rooms, Fosterdyke halted in a door-way on the port side. "Pantry and kitchen," he remarked. "I’m taking a couple of good cooks. All the stoves are electrically heated. There’s a dynamo working off the main shaft of each of the ’midship motors. The starboard one provides ’juice’ for the kitchen; that on the port generates electricity for the searchlights and internal lighting. Underneath are fresh water tanks and dry provision stores." On the port side corresponding to the kitchen were the air-mechanics’ quarters; while beyond the for’ard motor room the alley-way terminated, opening into a triangular space 30 feet long and 12 feet at its greatest breadth. "The crew’s quarters," explained Fosterdyke. "Ample accommodation for eight deck-hands and the two cooks. You’ll notice that the head-room is less than elsewhere. That’s because of the navigation-room overhead." The chums looked upwards at the ceiling. There was no indication of a hatchway of any description. "You gain the navigation-room from the alley-way," explained Sir Reginald, noting their puzzled glances. "Saves the inconvenience of disturbing the ’watch below’ by having to pass through their quarters. Up with you, Kenyon. Thank your lucky stars you’re not a bulky fellow. Mind your head against that girder." Bramsdean followed his chum, the baronet bringing up the rear.