Part 2 (2/2)

'Very pretty,' announced Algy cynically. 'Do they think we possess some means of making our-selves invisible ?'

'That 's all right, old boy, you needn't come,' murmured Biggles casually.

Algy started forward belligerently. 'What do you mean-I needn't come ? You can't leave me out of a show like this-'

'I'm sorry,' broke in Biggles blandly, 'but I rather gathered from your remark that you'd prefer to stay at home.'

'Well, think again,' snorted Algy.

'And that's no way to talk to your commanding officer,' returned Biggles. 'All right. We'

ll tell Roy to send the acknowledgement and then, with the map in front of us, think of ways and means. As a matter of fact, I did a job like this once before,' he added, as they went to the radio room and gave Roy instructions concerning acknowledgement of the orders.

Roy, with earphones clamped on his head, made a note on his pad. 'By the way, sir, I'm picking up a lot of Morse,' he said. 'I think it 's being sent out from somewhere not very far away. It 's in code, of course.'

'By jingo, if we could read it, it would be useful!' exclaimed Ginger. 'Do you think we could decode it ?'

'Not a hope,' answered Biggles promptly. 'What point would there be in using a code that could be deciphered by the enemy ? The only way official messages can be deciphered in war-time is with the official key, and that 's something we're not likely to get hold of. I imagine the British government would be only too pleased to pay a million pounds for the German secret code at this moment. All the same, Roy, you can keep a record of any Morse you pick up-one never knows. Get that acknow-ledgement off right away.'

'Very good, sir.'

Biggles led the way back to the office and spread the map on the table. 'All we can do is memorize the spot,' he said, pointing with his forefinger, 'and work out the best way of getting to it. We shan't need three machines; two should be enough, one to do the job and the other to act as a reserve-and possibly a decoy. I'll think about that. If the weather is O.K. we may as well go to-night and get it over. Algy, go and dig out that box marked W.D. 6. I'll go and have a look at the sky. No,' he added as an afterthought, 'there 's no need for me to go. You go, Ginger, while I have a look at the map.'

Leaving Biggles pondering over the map, Ginger made his way along the catwalk. He stopped for a few minutes to speak to the Flight-Sergeant, who was still working on the Dingo, and then went on towards the mouth of the cave.

Even before he pulled the tarpaulin aside he was aware, from the shrill cries of the gulls, that some-thing unusual was happening outside. Thinking that possibly the cause was a coming change in the weather, for he knew that gulls often get excited at such times, he m0ved the heavy tarpaulin and looked out. Instinctively his eyes turned upwards to the birds. Normally the majority sat placidly on the ledges on the face of the cliff, but now they all appeared to be on the wing, and he was amazed at the number of them. The air was full of whirling white forms, thousands of them, wheeling and at the same time uttering discordant cries of alarm.

At first Ginger could see nothing on account of the birds, but as he stared he became aware that they seemed to be concentrating at two places, not very far apart. Focusing his eyes on the spot, he caught his breath sharply as he perceived the reason for the uproar. Two men in dark uniforms were creeping along a ledge ; in their ha.nds they carried baskets in which they were putting something which they were picking up from the rocks.

It did not take Ginger long to realize that they were collecting the eggs of the gulls, which were protesting at the outrage in the manner already described. For a full minute he stared at the two men as his brain strove to grasp the significance of their presence.

Unprepared for anything of the sort, he was for the moment completely taken aback ; but as his composure returned he realized that a boat of some sort must have brought them, and he looked along the foot of the cliffs to locate it. It was not hard to find. It was a small collapsible canoe. Sitting beside it, calmly- smoking a pipe, was a third man.

Again Ginger's eyes moved, for he knew that such a frail craft could not have made its way to the rock across the open sea, and what he saw turned him stiff with shock. Lying just off the entrance to the cove, not two hundred yards away, was a sub-marine, its grey conning-tower rising like a monu-ment above the deck. There was no need to question its nationality, for on the side of the tower was painted, in white, the single letter U. Below it was the number 159.

How long the submarine had been there, Ginger, of course, did not know, but it had evidently been there for some time, for several members of the crew were disposed about the deck, sunning them-selves in the autumn suns.h.i.+ne, while a line of was.h.i.+ng hung between the conning-tower and a circular gun turret.

Ginger was still staring, half stunned by shock, when he heard a noise inside the cave that galvan-ized him into frantic activity. It was the swish-swish of an engine as its propeller was turned preparatory to starting, and he knew that Smyth was about to test the Dingo. Releasing the tarpaulin which he was still holding, he tore back along the catwalk and nearly knocked the Flight-Sergeant into the water with the violence of his approach. He was just in time, for the Flight-Sergeant's hand was already on the starter.

'Stop !' he gasped. 'Don't make a sound.' Leav-ing the mechanic gazing after him, as if he had lost his reason, he dashed along to the records room, where he found Biggles and Algy still poring over the map.

Their eyes opened wide at the expression on his face. 'What 's wrong ?' snapped Biggles.

Ginger pointed down the cave. 'There 's a U-boat in the cove,' he panted.

There was dead silence for a moment. Then Biggles sprang to his feet. 'The d.i.c.kens there is,' he said tersely. 'What's it doing ?'

Briefly, Ginger described the situation.

'I'd better have a look,' muttered Biggles. 'There seems to be nothing we can do except sit quiet in the hope that it will soon clear off.'

'Suppose these bird-nesters find the cave ?' asked Ginger.

'It'll be the last birds'-nesting they do for a long time,' promised Biggles grimly.

'It's the U 159,' Ginger informed him.

Biggles clenched his fists. 'By thunder,' he swore, 'here's a chance. It was the U 159 that sank the liner Arthurnia without warning, so it would be just retribution if we handed it a basinful of the same medicine. It must be on its way back to its depot. Come on.'

He dashed off down the catwalk closely followed by the others, but nearing the tarpaulin he slowed down and peered cautiously round the end of it.

The U-boat was still in the same positi0n, but the men who had been ash.o.r.e, evidently having filled their baskets, were making their way back in the canoe. Reaching the submarine, they climbed leisurely on board.

'They seem to be in no hurry,' observed Biggles anxiously. 'I'm afraid we're going to have them hanging about for some time. Ginger, send the Flight-Sergeant to me.'

Presently the Flight-Sergeant came at the double, and Biggles gave him orders in a low voice. 'Get an armour-piercing bomb on each machine and cast off ready for instant action.' He turned to the others. 'If she finds the cave we shall have to go for her,' he explained. 'There are probably forty or fifty men on board, so if they once got ash.o.r.e we shouldn't have a chance. They'd radio our position to Germany, anyway, and probably plaster us with that heavy gun on the bows. Our machine-guns wouldn't be much use against that. I'm still hoping they'll go without finding us.'

An hour pa.s.sed, and still the submarine gave no indication of departure. Another hour went by ; the was.h.i.+ng was taken in and the deck cleared, but not until mid-afternoon did the sinister craft begin to turn slowly towards the open sea.

Biggles breathed a sigh of relief. 'She 's going,' he said. 'That 's the best thing that could happen for everybody.'

With her steel deck awash, the submarine ploughed its way slowly towards the south, the air-men watching it with mixed feelings of relief and regret, for such a mark might never again present itself.

Ginger, who had fetched a pair of binoculars, steadied himself against the rock and brought them into focus. 'How far is it away do you think ?' he asked Biggles.

'About a couple of miles-why ?'

'It 's stopped-at least, I think so. Yes, it has,' declared Ginger. 'There seem to be some officers on deck-they're looking at something on the water. By gosh 1 It 's coming back.'

Biggles grabbed the gla.s.ses-not that they were really necessary, for what Ginger had said was obviously correct. The submarine had swung round in a wide circle and was returning over its course.

'What's the idea ?' asked Algy. 'What could they have seen to bring them back ?'

Biggles snapped his fingers. 'I've got it,' he cried. 'Look!' He pointed at an iridescent stain that drifted from the mouth of the cave and spread in a long wavy line towards the southern horizon. 'They've spotted that oil,' he added sharply. 'They're on their way back to see where it's coming from. It'll bring them straight to the cave. Quick! The machines!

We've got to get that sub. or it 's all up with us. Pull that tarpaulin out of the way, Smyth.'

There was a rush for the machines. Biggles was away first, as he was bound to be, for the Willie-Willie was nearest the entrance and blocked the way of the others. The roar of its engine drowned all other sounds. Leaving a wake of churning water behind it, the machine shot through the entrance to the cave and raced on over the cove.

It b.u.mped once or twice as it struck the swell of the open sea, and then, after climbing for a moment or two at a steep angle, made straight for the U-boat.

Biggles knew that there was no time for tactics. In the first place the members of the submarine crew must have heard his engine start, and no doubt they could now see him.

That was not all. He knew that he had got to send the U-boat to the bottom before a wireless message could be sent to the sh.o.r.e, or a flotilla of destroyers would be round the islet like a pack of wolves round a wounded deer. It was in an attempt to prevent this happen-ing that Biggles roared straight at the submarine.

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