"Because in my judgment the flow is far more likely to be lava than mud, and if I must be wrong I'd rather my error were one that left us alive. I have no time at the moment to explain the basis of my judgment. I will be reporting our activities quite steadily from now on, and would prefer that you not interrupt unless a serious emergency demands it, or you get a call from Eileen.

"We are about three hundred yards away now. The front is moving about as fast as before, which suggests that the flow is coming only along this valley. It's only three or four feet high, so viscosity is very low or density very high. Probably the former, considering where we are. It's as black as the smoke column."

"Not glowing?" cut in Zaino thoughtlessly.

"Black, I said. Temperature will be easier to measure when we get closer. The front is nearly straight across the valley, with just a few lobes projecting ten or twelve yards and one notch where a small spine is being surrounded. By the way, I trust you're taping all this?" Again Zaino was reminded of the afternoon after school.

"Yes, Ma'am," he replied. "On my one and only monitor tape."

"Very well. We're stopping near the middle of the valley one hundred yards from the front. I am getting out, and will walk as close as I can with a sampler and a radiometer. I assume that the radio equipment will continue to relay my suit broadcast back to you." Zaino cringed a little, certain as he was that the tractor's electronic apparatus was in perfect order.

It struck him that Dr. Burkett was being more snappish than usual. It never crossed his mind that the woman might be afraid.

"Ren, don't get any closer with the tractor unless I call. I'll get a set of temperature readings as soon as I'm close enough. Then I'll try to get a sample. Then I'll come back with that to the tractor, leave it and the radiometer and get the markers to set out."

"Couldn't I be putting out the markers while you get the sample, Doctor?"

"You could, but I'd rather you stayed at the wheel." Hargedon made no answer, and Burkett resumed her description for the record.

"I'm walking toward the front, a good deal faster than it's flowing toward me. I am now about twenty yards away, and am going to take a set of radiation-temperature measures." A brief pause. "Readings coming. Nine 

 Prev. P 15/22 next