"Why not?" she demanded.
"I just took readings on the grid, here. The voltage and the
conductivity of the layer we draw power from, both depend on
ionization. When the intensity of sunlight drops, the voltage drops and
the conductivity drops, too. It's harder for less power to flow to the
area the grid can tap--and the voltage-pressure is lower to drive it."
"Don't say any more!" cried Riki. "Not another word!"
Massy was silent. They went down the last small slope. They passed the
opening of the mine--the great drift which bored straight into the
mountain. They could look into it. They saw the twin rows of brilliant
roof-lights going toward the heart of the stony monster.
They had almost reached the village when Riki said in a stifled voice:
"How bad is it?"
"Very," admitted Massy. "We have here the conditions the home planet
will have in two hundred days. Originally we could draw less than a
fifth the power they count on from a grid on Lani II."
Riki ground her teeth.
"Go on!" she said challengingly.
"Ionization here is down ten per cent," said Massy. "That means the
voltage is down--somewhat more. A great deal more. And the resistance
of the layer is greater. Very much greater. When they need power most,
on the home planet, they won't draw more from a grid than we do now. It
won't be enough."
They reached the village. There were steps to the cold-lock of
Herndon's office-hull. They were ice-free, because like the village
walkways they were warmed to keep frost from depositing on them. Massy
made a mental note.
In the cold-lock, the warm air pouring in was almost stifling. Riki
said defiantly:
"You might as well tell me now!"
"We could draw one-fifth as much power, here, as the same sized grid
would yield on your home world," he said grimly. "We are drawing--call
it sixty per cent of normal. A shade over one-tenth of what they must
expect to draw when the real cold hits them. But their estimates are
nine times too high." He said heavily, "One grid won't warm three
square miles of city. About a third of one is closer. But--"
"That won't be the worst!" said Riki in a choked voice. "Is that right?
How much good will a grid do?"
Massy did not answer.
The inner cold-lock door opened. Herndon sat at his desk, even paler
than before, listening to the hash of noises that came out of the
speaker. He tapped on the desktop, quite unconscious of the action. He
looked almost desperately at Massy.
"Did she ... tell you?" he asked in a numb voice. "They hope to save
maybe half the population. All the children anyhow--"
"They won't," said Riki bitterly.
"Better go transcribe the new stuff that's come in," said her brother
dully. "We might as well know what it says."
Riki went out of the office. Massy laboriously shed his cold-garments.
He said uncomfortably:
"The rest of the colony doesn't know what's up yet. The operator at the
grid didn't, certainly. But they have to know."
"We'll post the messages on the bulletin board," said Herndon
apathetically. "I wish I could keep it from them. It's not fun to live
with. I ... might as well not tell them just yet."
"To the contrary," insisted Massy. "They've got to know right away!
You're going to issue orders and they'll need to understand how urgent
they are!"
Herndon looked absolutely hopeless.
"What's the good of doing anything?" When Massy frowned, he added as
if exhausted: "Seriously, is there any use? You're all right. A Survey
ship's due to take you away. It's not coming because they know there's
something wrong, but because your job should be finished about now.
But it can't do any good! It would be insane for it to land at home.
It couldn't carry away more than a few dozen refugees, and there are
twenty million people who're going to die. It might offer to take some
of us. But ... I don't think many of us would go. I wouldn't. I don't
think Riki would."
"I don't see--"
"What we've got right here," said Herndon, "is what they're going
to have back home. And worse. But there's no chance for us to keep
alive here! You are the one who pointed it out! I've been figuring,
and the way the solar-constant curve is going--I plotted it from the
figures they gave us--it couldn't possibly level out until the oxygen,
anyhow, is frozen out of the atmosphere here. We aren't equipped to
stand anything like that, and we can't get equipped. There couldn't
be equipment to let us stand it indefinitely! Anyhow the maximum cold
conditions will last two thousand days back home--six Earth-years.
And there'll be storage of cold in frozen oceans and piled-up
glaciers--It'll be twenty years before home will be back to normal
in temperature, and the same here. Is there any point in trying to
live--just barely to survive--for twenty years before there'll be a
habitable planet to go back to?"
Massy said irritably:
"Don't be a fool! Doesn't it occur to you that this planet is a perfect
experiment-station, two hundred days ahead of the home world, where
ways to beat the whole business can be tried? If we can beat it here,
they can beat it there!"
Herndon said detachedly:
"Can you name one thing to try here?"
"Yes," snapped Massy. "I want the walk-heaters and the step-heaters
outside turned off. They use power to keep walkways clear of frost and
doorsteps not slippery. I want to save that heat!"
Herndon said without interest:
"And when you've saved it, what will you do with it?"
"Put it underground to be used as needed!" Massy said angrily. "Store
it in the mine! I want to put every heating-device we can contrive
to work in the mine! To heat the rock! I want to draw every watt the
grid will yield and warm up the inside of the mountain while we can
draw power to do it with! I want the deepest part of the mine too hot
to enter! We'll lose a lot of heat, of course. It's not like storing
electric power! But we can store heat now, and the more we store the
more will be left when we need it!"
* * * * *
Herndon thought heavily. Presently he stirred slightly.
"Do you know, that is an idea--" He looked up. "Back home there was a
shale-oil deposit up near the icecaps. It wasn't economical to mine it.
So they put heaters down in bore-holes and heated up the whole shale
deposit! Drill-holes let out the hot oil vapors to be condensed. They
got out every bit of oil without disturbing the shale! And then ...
why ... the shale stayed warm for years. Farmers bulldozed soil over
it and raised crops with glaciers all around them! That could be done
again. They could be storing up heat back home!"
Then he drooped.
"But they can't spare power to warm up the ground under cities. They
need all the power they've got to build roofs. And it takes time to
build grids."
Massy snapped:
"Yes, if they're building regulation ones! By the time they were
finished they'd be useless! The ionization here is dropping already.
But they don't need to build grids that will be useless later! They
can weave cables together on the ground and hang them in the air by
helicopters! They wouldn't hold up a landing ship for an instant, but
they'll draw power right away! They'll even power the helis that hold
them up! Of course they've defects! They'll have to come down in high
winds. They won't be dependable. But they can put heat in the ground
to come out under roofs, to grow food by, to save lives by. What's the
matter with them?"
Herndon stirred again. His eyes ceased to be dull and lifeless.
"I'll give the orders for turning off the sidewalks. And I'll send what
you just said back home. They ... should like it."
He looked very respectfully at Massy.
"I guess you know what I'm thinking right now," he said awkwardly.
Massy flushed. It was not dignified for a Colonial Survey officer to
show off. He felt that Herndon was unduly impressed. But Herndon didn't
see that the device wouldn't solve anything. It would merely postpone
the effects of a disaster. It could not possibly prevent them.
"It ought to be done," he said curtly. "There'll be other things to be
done, too."
"When you tell them to me," said Herndon warmly, "they'll get done!
I'll have Riki put this into that pulse-code you explained to us and
she'll get it off right away!"
He stood up.
"I didn't explain the code to her!" insisted Massy. "She was already
translating it when you gave her my suggestion!"
"All right," said Herndon. "I'll get this sent back at once!"
He hurried out of the office. _This_, thought Massy irritably, _is how
reputations are made, I suppose. I'm getting one._ But his own reaction
was extremely inappropriate. If the people of Lani II did suspend
helicopter-supported grids of wire in the atmosphere, they could warm
masses of underground rock and stone and earth. They could establish
what were practically reservoirs of life-giving heat under their
cities. They could contrive that the warmth from below would rise only
as it was needed. But--
* * * * *
Two hundred days to conditions corresponding to the colony-planet.
Then two thousand days of minimum-heat conditions. Then very, very
slow return to normal temperature, long after the sun was back to its
previous brilliance. They couldn't store enough heat for so long. It
couldn't be done. It was ironic that in the freezing of ice and the
making of glaciers the planet itself could store cold.
And there would be monstrous storms and blizzards on Lani II as it
cooled. As cold conditions got worse the wire grids could be held aloft
for shorter and shorter periods, and each time they would pull down
less power than before. Their effectiveness would diminish even faster
than the need for effectiveness increased.
Massy felt even deeper depression as he worked out the facts. His
proposal was essentially futile. It would be encouraging, and to a
very slight degree and for a certain short time it would palliate the
situation on the inner planet. But in the long run its effect would be
zero.
He was embarrassed, too, that Herndon was so admiring. Herndon would
tell Riki that he was marvelous. She might--though cagily--be inclined
to agree. But he wasn't marvelous. This trick of a flier-supported
grid was not new. It had been used on Saril to supply power for giant
peristaltic pumps emptying a polder that had been formed inside a ring
of indifferently upraised islands.
_All I know_, thought Massy bitterly, _is what somebody's showed me
or I've read in books. And nobody's showed or written how to handle a
thing like this!_
He went to Herndon's desk. Herndon had made a new graph on the
solar-constant observations forwarded from home. It was a strictly
typical curve of the results of coinciding cyclic changes. It was
the curve of a series of frequencies at the moment when they were all
precisely in phase. From this much one could extrapolate and compute--
Massy took a pencil, frowning unhappily. His fingers clumsily formed
equations and solved them. The result was just about as bad as it
could be. The change in brightness of the sun Lani would not be enough
to be observed on Kent IV--the nearest other inhabited world--when
the light reached there four years from now. Lani would never be
classed as a variable star, because the total change in light and heat
would be relatively minute. But the formula for computing planetary
temperatures is not simple. Among its factors are squares and cubes of
the variables. Worse, the heat radiated from a sun's photosphere varies
not as the square or cube, but as the fourth power of its absolute
temperature. A very small change in the sun's effective temperature,
producible by sunspots, could make an altogether disproportionate
difference in the warmth its worlds received.
Massy's computations were not pure theory. The data came from Sol
itself, where alone in the galaxy there had been daily solar-constant
measurements for three hundred years. The rest of his deductions were
based ultimately on Earth observations, too. Most scientific data had
to refer back to Earth to get an adequate continuity. But there was no
possible doubt about the sunspot data, because Sol and Lani were of the
same type and nearly equal size.
Using the figures on the present situation, Massy reluctantly arrived
at the fact that here, on this already-frozen world, the temperature
would drop until CO_{2}, froze out of the atmosphere. When that
happened, the temperature would plummet until there was no really
significant difference between it and that of empty space. It is carbon
dioxide which is responsible for the greenhouse effect, by which a
planet is in thermal equilibrium only at a temperature above its
surroundings--as a greenhouse in sunlight is warmer than the outside
air.
The greenhouse effect would vanish soon on the colony-world. When it
vanished on the mother planet--
Massy found himself thinking, _If Riki won't leave when the Survey ship
comes, I'll resign from the Service. I'll have to if I'm to stay. And I
won't go unless she does._