There came a day when Brica’s womb dried.

“But I am content,” Regina said to Leda, her half sister. They were sitting in the peristylium, the strange underground garden of the Crypt, where the mushrooms seemed to glow like lanterns. The three most senior women of the inner family were here: Regina herself, Leda, and Venus, granddaughter of Regina’s aunt Helena. “Brica has given me eight grandchildren—three boys, who have already started their apprenticeships in the world beyond, and five fine and beautiful workers for the Order. Nobody could do more.”

“Yes, Regina.”

“We are healthy stock—and our lives are long, in the shelter of the Crypt.”

It was true. It was six years after the visit of Ambrosius Aurelianus. Regina was now in her seventies, and Brica herself was over fifty. Even at Rome’s height, few people had lived beyond forty, fewer still past fifty; and in the current times of turmoil, with rampant disease, poor supplies of food and water, and assaults from barbarians, that average was dropping steadily. But not in the Crypt.

“And, as we live long, we stay fertile. But I am concerned for Brica herself.” Now that she was barren, Brica seemed exhausted, worn out by the relentless demands of childbirth; she drifted around the Crypt purposelessly. “We must make her comfortable, reassure her . . .”

“But,” Venus said delicately, “there is the question of the nursery.”

Regina said vaguely, “The nursery?”

“The youngest child is already three,” said Leda. “We need more babies. We must maintain—” She gestured.

“A flow.” Regina opened her gummy mouth and cackled. “Like the great sewers. We need to push babies in at one end of the system, to ensure a nice smooth flow of effluent at the other.”

“Not quite the way I would have put it,” said Venus. Since being elected to the Council she had grown in confidence, and had developed a dry wit. “But, yes, you’re right.” She added delicately, “We need to decide on a—replacement—for Brica.”

Leda nodded.

Of course they were right; this was the logic of how they had been running the Order, already for more than twenty years.

It was the slow unfolding of the instinctive vision Regina had always held in her head. Space would always be limited here. If all the female members of the family proved as fecund as Brica, there would soon be no room left. So, just as Regina had ordered with Agrippina, only a handful of women were encouraged to have children at any one time. Their siblings and growing daughters were expected to assist these central mothers to bear more young, to raise more sisters, even at the expense of families of their own. They should stay childless through the use of contraceptives, or abstinence—or best of all by simply delaying their menarche through the mysterious workings of their bodies, as had happened to Brica’s second daughter Julia, and a number of other girls since.