"Yes, I see it now," replied his comrade, bringing his glasses to bear on the object for which he had been keenly searching for some minutes.
"Straight road now. Give her a few more points eastward."
Dastral altered the controls a little, and, banking slightly, the hornet came round smartly upon her new course, which, for the rest of the journey to the coast, was almost due east.
The continuous roar of the engines and the whir-r-r of the propeller made conversation almost impossible, except for a few short, jerky sentences, uttered in a loud, shrill voice, and accompanied by corresponding gestures.
The world beneath them was waking up now, for the two aviators could see the smoke ascending from the chimneys of a few scattered farmhouses and cottages. The birds, too, were astir, and the larks, mounting up towards the sun, made sweet music which was drowned in the whir-r-r of that strange-looking bird of prey, which sailed serenely above them. Instinct, however, made the songsters shrink and flee away from that hawk-like menace with stretched-out wings, for they evidently feared that it might swoop down upon and destroy them.
"Dover!" shouted the observer suddenly, as the Cinque Port came into view.
"Yes, by Jove! So it is. I hope they won't turn the guns of the fort upon us."
"No fear. They'll have been warned of our coming by now."
A minute later, they opened out the sea, the forts, and Shakespeare's Cliff, and within another three minutes they had crossed the boundary of sea and land, and at a tremendous altitude were gliding over the Channel.
"Nine thousand!" yelled Dastral, turning his head towards Jock, after casting a brief glance at his indicator.
"Now let her rip," cried the other, for in climbing to get the required height to rush the Channel, the machine had lost speed.
"Right-o!" came the answer.
So, in order to get speed quickly, Dastral did a little nose dive of about three hundred feet, then flattened out again, intending to rush the Channel at one hundred and twenty miles an hour, lest they should slip unconsciously into an air-pocket.
As he did so, he noticed a flash of fire followed by a puff of white smoke down at the Castle.
"A signal!" shouted Jock, who had noticed the occurrence at the same instant.
"Yes, they want to speak to us," and with a circling sweep the machine came round as Dastral pulled the joy-stick hard over, and swept back again until he hung right over Dover Castle.
"Can you make it out, old man?" asked the pilot.
"Yes, I have it," cried Fisker, whose eyes had been glued to a spot on the Castle grounds just at the top of the hill overlooking the naval harbour.
"What is it? Do they want us to go down?"
"No. The Commander of the fort says there are several enemy submarines in the Channel, and requests us to keep a sharp look-out for them as we cross over."
"Cheery-o, Jock! That's good news. I'm going to drop down a bit, then. There's a D.S.O. for you if you spot one. Here goes!" And with that, Dastral jammed over the controls again, and did a neat nose dive of two thousand feet, looping the loop once or twice just to express his joy, and give vent to his feelings.
Jock had picked up this information from a few white strips of calico, which had been stretched out in a curious fashion within the Castle grounds. To a trained observer like Fisker, it was mere child's play to read a code signal like that.
And now the daring joy-riders, keenly watched by hundreds of eyes far down below, left the shore once again, and the naval harbour with its shipping, and headed for the French coast, watching the surface of the sea as though they would read its secret.
"East-south-east, Dastral! That's the course till we sight the opposite shore," shouted Jock to his comrade, who, he thought, in his excitement and eagerness to spot a submarine lurking in the depths, might miss his way, as many a brave aviator before him had done.
"Right-o!" came the answer to this reminder, for the French coast was hid as yet in the morning mist. Then the course was altered slightly once again, in order to make a proper landfall on the other side.
They were flying low now, much lower than the usual regulations permitted, for it is necessary to keep a good altitude in crossing the Channel, not only because of the chance of running into a stray air-pocket, but to enable one to 'plane to safety should anything go wrong with the engines, for only a seaplane can ride the waves like a ship; and this was no seaplane they were riding to-day.
Far down below them they could see the patrol boats hunting for their prey. They could also see the mine-sweepers at work, clearing the fairway from those foul nests of floating mines which the crafty foe had been busy laying with their submarines. Once or twice they thought they could make out some dark-grey object like a mine or sunken vessel beneath the surface of the water.
A string of mine-sweepers were stretched out below them now. They could see them distinctly, could see even the long nets that trailed between them, for the sun was gaining power and the morning mists were rolling away. The grey expanse of water took on another hue, changing from a dull grey to a greenish tint, with patches here and there of deep blue, where the water deepened, or the surface of the mirror reflected a corresponding patch of the azure above.
Keenly now they searched the face of the deep for any dark speck, for, from an aeroplane, it is possible to look far down, often even to the bed of the sea; but as yet they saw nothing, save an occasional piece of wreckage, which had probably detached itself and floated from the treacherous Goodwins, away to the eastward and the northward–those treacherous shoals which hold the remains of so many gallant barques and vessels, from the Roman galley to the modern liner.
They had not long left the mine-sweepers on their port quarter when Jock, through his glasses, noted something like a string of porpoises, which, owing to the motion of the waves, appeared to be travelling along. They seemed so regular and orderly in their movement, however, that he was about to pass them over. Thinking, however, that he would like to call Dastral's attention to them, he shouted:–
"Starboard bow, Dastral! Look at 'em! What are they? Not mines, surely. Look like porpoises, only they're not dark enough, and they don't tumble about much."
Dastral peered over the side of the cockpit and looked down.
"Can't say," he ejaculated.
"Let's go down a bit lower, old man," said Fisker.
"Aye, aye. Hold tight!" cried the pilot, for he noticed that Jock was standing up and leaning over, unstrapped.
"Right away! I'm all right," replied the observer, squatting down, and pressing his knees against the knee-board, which is the life-line of the aeroplane.
And down they went in a graceful nose-dive till they were within five hundred feet of the surface of the water, with the engines shut off. Then, as they flattened out, both men peered over the side again, and Dastral was the first to exclaim:–
"Porpoises be hanged! They're German mines. A whole string of them floating about in the fairway, ready for the first ship that comes along. The dirty Huns!"
"Snakes alive! So they are. Now I can make them out quite plainly; I can even see the horns and contacts through my glasses. Phew! There'll be a deuce of a mess shortly unless they're cleared up."
"Look alive, old man, or there'll be trouble!" shouted the pilot.
"How so?"
"See that ocean tramp coming up Channel. She's a seven thousand tonner, and her cargo's worth a couple of hundred thousand. She'll be right on the string of mines directly, and then–gee whiz!–there'll be fireworks, and another valuable cargo will have gone to Davy Jones' locker."
The mine-sweepers were about a couple of miles away by this time, but the Commodore of the little fleet had seen the rapid nose-dive of the hornet, and knew that something unusual was happening.
He