The cell was used for two purposes: to give people who had learned Jackson and Sarah's secret time to adjust before being set loose or influenced to forget, and to hold newly turned vampires until they could be trusted to not wipe out the population of a small city.
As he approached the door, Jackson thought about the last time he used this room. Cassandra Davis was a vampire groupie who desperately wanted to be turned. He agreed, since she was pretty enough, and he hadn't turned anyone for decades. The life force would be welcomed and the Exemplars would grant permission easily. Jackson enjoyed the surge of power a vampire garnered from turning a human, but having to snack carefully on one person for days on end, always running the risk of killing them, took all the fun out of feeding for him. Sarah offered a great deal of help here. She would set up transfusions if there was danger the human might die, and had to twice for Cassandra.
Sarah rarely fed on humans anymore. Sometime in the 40s she got it in her head that they were violating people, and developed a guilty conscience. Jackson would argue, "When all is said and done, if you handle them properly, you know they love it too."
"That's just it, we're handling them, and it feels wrong to me now." These days, she only fed on lovers when they had accepted her vampirism and wanted to share that intimacy. Sarah obtained her blood by paying people to let her draw it the old fashion way. She would claim to be a research scientist. You hand a bum or junkie $500 for a pint of blood, they do not ask too many questions. A pint here, a pint there and before you knew it she had her own little blood bank. She drank blood from a glass, just like scotch.
Jackson would smirk. "Not the same as fresh."
It took a full two weeks to turn Cassandra and it ended in disaster. Usually, when a person is turned, he or she is anxious to take off and explore their new power, so you keep them a while, carefully feeding and teaching them how to control the bloodlust. Then off the newborn goes to start a life of vampirism, just like a bird leaving the nest. Unfortunately, Jackson realized too late that Cassandra was a crazy bitch, and needy as hell. She followed him like a lost sheep. In the end, he finally lost her somewhere in Russia. God! What a pest. The power ended up to be hardly worth the aggravation.