Next came the 'midship compartment, over which was the conning-tower. Here the officers "messed", each officer having a small separate cabin, while a large "ward-room" afforded comfortable quarters for meals and recreation. Here, too, was the wireless-room. A steel ladder communicated with the conning-tower, which, when necessary, could be hermetically cut off from the rest of the interior by means of sliding panels working in indiarubber-shod grooves. Underneath the officers' quarters was the 'midships torpedo-room. This was an innovation in the "R" Class. It enabled a torpedo to be discharged broadside, this obviating the necessity of keeping the submarine "bows-on" to her prey. Fore and aft were two tubes--mounted on "racers" or quadrants of a circle consisting of toothed gun-metal rails. The combined length of this torpedo and its tube was too great to allow the weapon to be "launched in" when the latter was trained athwartships. Consequently the tubes were loaded in a fore-and-aft position and swung round until the mouths engaged with a corresponding pair of flanged, water-tight tubes through either side of the hull. From the broadside tubes torpedoes could be trained through an arc of 30 degrees. Compartment 4 was devoted almost entirely to machinery--propelling, pumping, and steering--while the aftermost subdivision contained the oil-fuel tanks and electrical storage batteries. In each compartment were water-ballast, trimming-tanks, and air-locks for life-saving purposes in the event of the vessel being sunk in comparatively shallow water. R19 had refilled and replenished stores and provisions. She was ready to "sail" at a moment's notice, directly the Lieutenant-Commander received orders from the Commander-in-Chief's office and had obtained the latest charts of the Baltic from the dockyard chart-room. In the absence of the Hon. Derek Stockdale, the Sub reported himself to Donald Macquare, the senior lieutenant, who specialized in torpedo-gunnery, a tall, big-boned Scot whose abruptness of manner was apt to form a temporary disguise to a large-hearted nature. Macquare was still a young man--the submarine service had no need for middle-aged officers--and, without professing any claim to being a "Popularity Jack", was well liked by his brother officers and fearlessly respected by the crew. "Good time?" he asked laconically. "Rather!" replied the Sub. "And now I'm ready for anything--even another hand at bridge. I won the princely sum of one and eightpence from you last time, do you remember?"