Level 7

MARCH 27

I am trying to divert myself by learning what I can about the technical arrangements on Level 7. In their way they are pretty remarkable. This is a very small world, but it seems to be quite self-sufficient. Although it lies so deep underground it has its own supply of energy, food and all the other essential commodities needed by its crew. We might be on a ship, equipped for an endless voyage.

For one thing, we shall never run out of fuel. Everything here works by electricity from dynamos powered by an atomic reactor which can supply all the energy we want for a thousand years. There is nothing new in this principle, but when you think of all the gadgets which are using up electricity twenty-four hours a day down here you appreciate how impossible life would be without an atomic reactor.

The problem of storing nourishment must have been more complicated; but at dinner today somebody provided some interesting information about that. (People have started to be more talkative lately.) He said—and he appeared to know what he was talking about—that dehydrated food in enormous quantities is stored in a huge deep-freeze. At each meal the necessary amount is automatically taken out of the freeze, warmed, mixed with water and served on our plates. Being dehydrated, it takes up very little space. Even so, the storage of enough to feed 500 people for 500 years is no simple matter.

The man’s mention of 500 years made everybody fall silent for a few moments. I expect the others were thinking the same as I was. I sometimes feel as if I have been down here months already, not just days; and to think of Level 7 in terms of centuries is beyond my imagination.

One of the women made it her task to break the silence by asking how enough water could be stored underground. “There is no dehydrated water,” she added, and was rewarded by a few bleak smiles from the rest of us.

However, we gathered from the expert that there is no need to store water, and that the supply is unlimited. In fact it is the only commodity which can never run short. It reaches us from deep underground sources, inexhaustible because of precipitation.

“At first,” the expert said, “it was feared that the water might become contaminated in the event of an atomic war. Then it was found that the thick layers of earth through which the water has to pass on its way down act as excellent filters. We stand no risk of drinking impure water.”

Our meal was nearly over, when somebody raised the question of refuse. The disposal of sewage and other rubbish on Level 7 was surely as big a problem as the storage of food.

But this problem too has been solved with great ingenuity. All the refuse is led through an ordinary drainage system into a special machine which separates off the fluids. These are pumped out of Level 7 to an earth level where they are absorbed, and the dehydrated solids are compressed and transferred to a special storage space. Logically enough—though the idea struck me with a rather chilly surprise when I heard it—this space is the space left by the food we have consumed. The planners of Level 7 could not afford to waste an inch; so the deep-freeze which contains the food also holds, on the other side of a sealed but moving wall, the sewage. As the stock of food decreases and the bulk of refuse increases, so the moving wall is pushed along by the difference in pressure and one substance takes up the space left by the other. This is a very slow process; but in 500 years what is now a filled food-storage room will have become a large sewage pit.

All this is quite interesting, but I find the idea that it will take 500 years to fill that pit rather oppressive.