When waves are first formed they are short and steep, but if the wind continues to blow in the same direction across a considerable stretch of sea, their length and height increases, and their crests, on which the wind has the greatest effect, tend to drive faster than the main body of the waves and so break forward in a smother of white foam.
In deep water waves have no motion of translation—that is, the particles, of water do not move horizontally, but merely up and down vertically. It is only the waves of force, born of the energy of the wind, that move across the sea. In shallow water the troughs of the waves are retarded, with the result that they become steep, the crests break, and the water rushes forward with great violence.
Water in mass played upon by the wind is not the tractable element it appears when running through our pipes, contained in shaving-mugs, or filling baths. Thus, while a land-machine pilot, down safely with engine failure, has all his worries behind him, the pilot of a seaplane or flying-boat, down at sea, has all his troubles to come, unless the weather be fine, help near at hand, or his craft very seaworthy.
Everything seemed to be set fair for a fine day on the 24th of May when Flight Sub-Lieutenant Morris and his wireless observer went down to the slipway at Westgate, a seaplane station on the East Coast south of Felixstowe.
At the top of the slipway, on its wheeled beach trolley, stood their machine, a float-seaplane with a single engine. It had wings which folded back along the fuselage, when it was living on shore, in order to economise shed space. A party of men were swinging the wings into place and locking them in flying position. The two large flat-bottomed floats were made of brightly varnished wood. The bombs were slung on the fore-and-aft centre line beneath the fuselage, above and between the floats. There was a third small float under the tip of the tail, and behind this float was a water rudder, a rudder operated with the air rudder, but which was used for steering the seaplane when it was down on the water. It looked very ship-shape; a small stock anchor, with line neatly coiled, which was shackled to one of the floats, giving the right sea-going touch.
When the machine was ready the wireless operator stepped up on the port float, climbed up a little wire ladder, and settled himself into his cockpit, where he had his wireless apparatus, bomb-sight, and machine-gun on a ring. By standing up he could fire forward over the top plane. Morris climbed up after him into the control cockpit. He was in front of the wireless observer, for the crew of two in a float-seaplane sit tandem.
Morris, looking over the side, saw that everybody was clear. He switched on the magnetos and opened a cock in an air-bottle. A stream of compressed air hissed into the cylinders of the engine and turned it over, the pistons sucked in the petrol mixture, a spark fired it, and the high-speed engine began to run smoothly. He warmed up the oil, tested the engine full out, and then gave the signal for the chocks to be knocked away. The working party ran the seaplane down into the water. It floated clear of the trolley.
When the engine was opened out the tail of the seaplane came up to the horizontal. It leaped forward, planing along the top of the water on the two floats. As the pilot pulled back the controls it skipped along with only the rear edges of the floats touching, taking little jumps off the surface as it encountered the tiny waves. And then it was in the air.
After spending some hours over the North Sea, Morris started for home. He was feeling very hungry, and began thinking about his dinner with pleasure. In half an hour he would have his legs tucked under the table in the mess. Suddenly he heard the noise of his engine and knew that something was wrong, for a pilot is not conscious of the roar of his engine when it is running properly. It began to miss. The revolutions dropped. And within a minute it stopped and the machine had been landed on the water.
They were down thirty miles out to sea in one of our deep mine-fields. It was a very big mine-field. It started from an east and west line a short distance south of the North Hinder and continued to a line running east just above the North Foreland. Of course there were no ships in sight and no chance of any appearing.