Then, as Fuller had foretold, came the first of a succession of terrific explosions, as a large bomb from the leading seaplane crashed into a shell store.
Although the prisoners could not see the actual damage done to the building, they knew that it no longer existed. A dense black cloud thrown skywards by the detonation threw such a dark shadow that sunlight gave place to a gloom resembling twilight. Thousands of projectiles, hurled far and wide, burst with dire results. Scorched and maimed bodies of victims were projected in unrecognisable masses for nearly two hundred yards from the actual scene of the disaster.
For some moments bombs fell like rain. Several of the gun emplacements in the dunes were utterly wrecked. In others the guns were temporarily disabled by quantities of sand that, hurled right and left by the bombs, choked the bore and clogged the delicate mechanism of the sights and training gear.
The torpedo-boats in the basin also had a rough handling. Several, to escape destruction, put out to sea, but in the confusion many collided in the narrow, intricate channel. Others were sunk alongside the quays. Of the forty naval vessels belonging to the port, twenty-two only escaped.
Expecting every moment to find the building collapse over their heads, Tressidar and his companion stuck to their posts at the window, Presently they saw one of the huge armoured cars proceeding at a furious pace down the military road behind the dunes. As it tore along, its obliquely-pointed quick-firer spat venomously at the British seaplanes until a bomb, falling quite a hundred feet from the car, tore a deep hole in the roadway. At the same time a flying fragment of metal found its way through the narrow slit in the steel plating behind which sat the driver. The man was either killed or seriously wounded, for the powerfully engined vehicle was no longer under control. Gradually, at a speed of approximately forty miles an hour, it described a curve in a right-handed direction, while the gunners, their attention fixed upon the elusive targets a thousand feet or more above their heads, were in ignorance of the danger that threatened them.
"Dash it all!" exclaimed Tressidar excitedly. "That car will barge into something in half a shake."
Already the vehicle had left the broad road and was ploughing with no apparent effort through the sand. It was heading towards the prison buildings.
Through the outer palisade it came, hurtling the steel rods right and left. Then, without checking its headlong career, the car wrenched its way through the double lines of barbed wire, carrying away yards of fencing as it did so.
The anti-aircraft gun had now ceased firing. The gunners, aware of the fact that the car was a derelict, but unable to gain the steering compartment, were helpless.
"Stand by!" exclaimed Tressidar.