‘Ass!’ said the Director, breaking a long silence. ‘Hasn’t it occurred to you that an Epsilon embryo must have an Epsilon environment as well as an Epsilon heredity?’

It evidently hadn’t occurred to him. He was covered with confusion.

‘The lower the caste,’ said Mr. Foster, ‘the shorter the oxygen.’ The first organ affected was the brain. After that the skeleton. At seventy per cent. of normal oxygen you got dwarfs. At less than seventy, eyeless monsters.

‘Who are no use at all,’ concluded Mr. Foster.

Whereas (his voice became confidential and eager), if they could discover a technique for shortening the period of maturation what a triumph, what a benefaction to Society!

‘Consider the horse.’

They considered it.

Mature at six; the elephant at ten. While at thirteen a man is not yet sexually mature; and is only full grown at twenty. Hence, of course, that fruit of delayed development, the human intelligence.

‘But in Epsilons,’ said Mr. Foster very justly, ‘we don’t need human intelligence.’

Didn’t need and didn’t get it. But though the Epsilon mind was mature at ten, the Epsilon body was not fit to work till eighteen. Long years of superfluous and wasted immaturity. If the physical development could be speeded up till it was as quick, say, as a cow’s, what an enormous saving to the Community!

‘Enormous!’ murmured the students. Mr. Foster’s enthusiasm was infectious.

He became rather technical; spoke of the abnormal endocrine co-ordination which made men grow so slowly; postulated a germinal mutation to account for it. Could the effects of this germinal mutation be undone? Could the individual Epsilon embryo be made to revert, by a suitable technique, to the normality of dogs and cows? That was the problem. And it was all but solved.

Pilkington, at Mombasa, had produced individuals who were sexually mature at four and full grown at six and a half. A scientific triumph. But socially useless. Six-year-old men and women were too stupid to do even Epsilon work. And the process was an all-or-nothing one; either you failed to modify at all, or else you modified the whole way. They were still trying to find the ideal compromise between adults of twenty and adults of six. So far without success. Mr. Foster sighed and shook his head.

Their wanderings through the crimson twilight had brought them to the neighbourhood of Metre 170 on Rack 9. From this point onwards Rack 9 was enclosed and the bottles performed the remainder of their journey in a kind of tunnel, interrupted here and there by openings two or three metres wide.

‘Heat conditioning,’ said Mr. Foster.

Hot tunnels alternated with cool tunnels. Coolness was wedded to discomfort in the form of hard X-rays. By the time they were decanted the embryos had a horror of cold. They were predestined to emigrate to the tropics, to be miners and acetate silk spinners and steel workers. Later on their minds would be made to endorse the judgment of their bodies. ‘We condition them to thrive on heat,’ concluded Mr. Foster. ‘Our colleagues upstairs will teach them to love it.’

‘And that,’ put in the Director sententiously, ‘that is the secret of happiness and virtue—liking what you’ve got to do. All conditioning aims at that: making people like their unescapable social destiny.’