"Maybe Father's worse."
They tried to conserve their breath after that for running and climbing. Once Jon broke the silence. "Turn your oxygen a little higher, Jak," he said as he twisted the small lever at his own shoulder to increase the flow of the strength-giving energy.
They were panting and winded by the time they reached the top of the hill. But they disregarded fatigue in the face of their mother's probable danger—or their father's.
Jon looked quickly to one side and then the other. As Jak topped the ridge he saw his brother run some twenty feet or so to where he had spotted a fairly smooth downward slope. Down this the younger boy launched himself feet first, sliding on his suit's back. Jak instantly realized the reason, and threw himself after his brother.
In less than a tenth of the time it would have taken them to climb down, the boys were at the foot of the hill. They struggled to their feet and started off toward the ship. Both were again shaken and sorely bruised from their rough slide, but they trotted on. Mother had called—nothing else mattered.
As they came closer to the ship they saw her reason for summoning them.
All about the outer lockdoor were those strange crystalline structures, growing swiftly. As the two boys came still closer, they could see that streamers of the crystals had already reached the lower edge and were trying to force their way through the almost imperceptible crack.
"They'll never get ... through there," Jon panted as he raced the last few feet.
"Don't see ... how they can ... but watch 'em." Jak waded into the alien, growing things. His gloved fists smashed right and left as he spoke. Jon was already doing the same.
But whether these crystal-beings were of a different type from those that Jak had broken in the distant valley, or just what was the reason, the boys now found it more difficult to break these crystals down.