How did Mrs. Clonkers punish the children at the orphanage in The BFG?

Before Sophie is kidnapped by the BFG, she lives at an orphanage run by a mean old lady named Mrs. Clonkers. She had very strict rules that included folding your clothes and not getting out of bed at night, even if you had to use the bathroom. Sophie tells the BFG that she hated living there because Mrs. Clonkers punished them if they broke any of her rules. For breaking a rule, the punishment was being locked in the cellar.

'It was horrid,' Sophie said. 'We used to dread it. There were rats down there. We could hear them creeping about.'

As bad as the orphanage was, though, when she first gets to giant country Sophie thinks it is even worse! The BFG feels terrible about how Sophie was treated, and even worse for bringing her to giant country. Of course it all turns out well in the end, and Sophie and the BFG get to live next-door to one another in London.