To come up abruptly within the lagoons and interior waterways of Arron. Perhaps then, on the windward side of the city, to loose their deadly lethal gas.
Two hours, at least, for them to reach Arron. The lights crawled under us; and a vagrant ocean current drifted us away, so that presently we dared fling on our rocket-stream power and speed back to Peters. He was ready now, and his hundred men embarked in the fifty little cylinders. And the five hundred girls were ready, too. I saw them on the ocean surface, from the turret of our cylinder as we bobbed to the top. An amazing army of green-clad nymphs. Each of them had a ray-cylinder of our fifty foot projector. They lay, each of them on a six-foot little sub-sea sled, powered, like our cylinders, with the oxo-hydro gas-streams. In effect, a narrow, six foot long raft, with a hooded bow that housed the control mechanisms and protected the girls' faces from the rush of water. The girls' bodies had a weight of about the same as water. Specific gravity of 1. And the sled with its mechanisms was adjusted to be the same. Girl and sled—neither to float nor sink, but approximately to hang poised. And thus, with little tilting fins on the sled's sides, and lateral and vertical bow and stern rudders, the power would thrust them down into the depths and up again at will.
We started. Running at first on the surface, the largest of our little cylinders with Peters and two of his skilled men led us in a line. And behind us came the girls, in squads of twenty, each with a leader. They had often practiced it, for sport and for the possibility of such a time as this.
As we passed the Water City, we submerged to fifty feet. I turned to look back through our turret. Like darting fishes the girls came down, still holding their formation as we swept on through the green-black depths to battle.
VII
For a time we ran with short-range headlight beams preceding us, then, as we neared the area where we knew Tollgamo's ships should now be, we ran dark. But still there were the glowing, bubbling rocket-stream tails of our fifty little cylinder boats; and the rocket-streams of the girls' diving sleds. And our swift passage through the water left a phosphorescent wake so that the area all around us glowed, opalescent with a pallid, eerie light.
Leh and his father had arranged the tactics of battle which we hoped we could employ. He explained them to us now. Peters' larger cylinder was banded with white alumite stripes so as to be easily distinguishable. Its light signals would give us orders.
"There is a ridge," Leh was saying. "It crosses from the promontory head of the metal mountains across to the Arron forests. We think Tollgamo will follow it as his best method of approach."
It was a transverse ridge, lying at an average of not much more than fifty feet beneath the surface. A submarine plateau, in main extent some ten miles long and a quarter of a mile wide, with deeps on both sides of it where the bottom dropped sharply away, in places to unfathomable depths. If we could catch the Tollgamo vehicles in that area it was our best chance for a shallow attack. And that, we needed. The girls especially, could not dive into the lower, higher pressures.