‘Now, now, you mustn’t get in a state, dearie,’ replied Boyd. ‘Too much work is making you peevish. Here’s lunch. Just try to pick a bit of chicken, cold one, and you’ll rise from the table like a lion refreshed.’ ‘At one time,’ said Raymond, sitting down, ‘we didn’t get much at sea, but in these new boats I always look forward to the trip on account of the change of grub.’ ‘And yet we growl,’ put in Boyd. ‘I never met any one at sea yet who hadn’t a moan about the food.’ The meal was eaten in shirt sleeves, as the boat was getting rather hot now that the sun was well up, and after the fruit and custard had disappeared Raymond leant back with a yawn. ‘Pity we can’t smoke,’ he said. ‘I’m feeling damn tired. You keep a watch on the “perisher”[7] this afternoon, Seagrave.’ ‘All right. Turn in and trust me to let you know if we bump a “mouldy.”[8] I won’t forget.’ In the after compartment the mess tables were down and the men were getting outside their meal seated on stools, the deck, or anything that came to hand. The gyro buzzed on one side of them, and the rattle of the steering-gear formed an accompaniment, which, however, did not seem to upset their appetites. Young men mostly, with here and there a grizzled petty officer for leavening, they moved about with that deftness which men acquire who are accustomed to live in confined spaces. By-and-by, Seagrave went up the control room shaft and unscrewed one of the brass ports, disclosing a small circle of thick glass. Through this the water could be seen looking intensely blue, while on glancing up he could see the surface thirty feet above, which appeared like a blue ceiling or a large sheet stretched over the boat. Occasionally the under side of a piece of driftwood could be seen floating on the surface and the fore-deck, and the gun stood out sharply defined. The atmosphere was bad up here, as all the foul air drifted upwards, and Seagrave soon screwed back the post and returned to his book in the fore compartment. Every ten minutes came the monotonous order, ‘Eighteen feet,’ the periscope was hoisted and lowered, and the boat descended to the thirty-foot level. Nearly every one was asleep, the heavy atmosphere making them drowsy, and it was very quiet and peaceful, when the second coxswain, who was at the hydroplanes, called out sharply,-- ‘Getting ’eavy, sir! I can’t ’ol ’er up!’ Now, no submarine can descend to an unlimited depth, because the external pressure becomes too great, and below two hundred feet or so they are liable to crush and flatten in like pancakes. Also if she begins to leak owing to excessive depth, water may get to the batteries, whereupon chlorine gas will form and suffocate all hands. Therefore a decent haste is necessary if at any time, owing to an increase of water in the bilges, the boat becomes heavy and has what is known as ‘negative buoyancy.’ Raymond and Seagrave hurried into the control room, the captain giving his orders as he came.