"One hundred power."

The green flecks were larger now, very clear.

"We think that's our organism. We have observed it growing; it turns purple, apparently at the point of mitotic division."

"Spectrum shift?"

"Of some kind."

"One thousand power," Leavitt said.

The screen was filled with a single green spot, nestled down in the jagged hollows of the rock. Hall noticed the surface of the green, which was smooth and glistening, almost oily.

"You think that's a single bacterial colony?"

"We can't be sure it's a colony in the conventional sense," Stone said. "Until we heard Burton's experiments, we didn't think it was a colony at all. We thought it might be a single organism. But obviously the single units have to be a micron or less in size; this is much too big. Therefore it is probably a larger structure—perhaps a colony, perhaps something else."

As they watched, the spot turned purple, and green again.

"It's dividing now," Stone said. "Excellent."

Leavitt switched on the cameras.

"Now watch closely."

The spot turned purple and held the color. It seemed to expand slightly, and for a moment, the surface broke into fragments, hexagonal in shape, like a tile floor.

"Did you see that?"

"It seemed to break up."

"Into six-sided figures."

"I wonder," Stone said, "whether those figures represent single units."

"Or whether they are regular geometric shapes all the time, or just during division?"

"We'll know more," Stone said, "after the EM." He turned to Burton. "Have you finished your autopsies?"

"Yes."

"Can you work the spectrometer?"

"I think so."

"Then do that. It's computerized, anyway. We'll want an analysis of samples of both the rock and the green organism."

"You'll get me a piece?"

"Yes." Stone said to Leavitt: "Can you handle the AA analyzer?"

"Yes."

"Same tests on that."

"And a fractionation?"

"I think so," Stone said. "But you'll have to do that by hand."

Leavitt nodded; Stone turned back to the isolation chamber and removed a glass dish from the light microscope. He set it to one side, beneath a small device that looked like a miniature scaffolding. This was the microsurgical unit.

Microsurgery was a relatively new skill in biology—the ability to perform delicate operations on a single cell. Using microsurgical techniques, it was possible to remove the nucleus from a cell, or part of the cytoplasm, as neatly and cleanly as a surgeon performed an amputation.

The device was constructed to scale down human hand movements into fine, precise miniature motions. A series of gears and servomechanisms carried out the reduction; the movement of a thumb was translated into a shift of a knife blade millionths of an inch.

Using a high magnification viewer, Stone began to chip away delicately at the black rock, until he had two tiny fragments. He set them aside in separate glass dishes and proceeded to scrape away two small fragments from the green area.

Immediately, the green turned purple, and expanded.

"It doesn't like you," Leavitt said, and laughed.