"Yes. If I were you, I'd be more concerned about the circumvention of your locks and wards than about the chair itself. The readings I've been able to take from the benches suggest, rather than any dark magic, a vibrating and a self-masking charm, very likely accomplished through enchantment--I think arithmancy the most likely base--set on each affected item rather than from afar on the set as a whole. But perhaps you'll be able to learn more," he knows he doesn't need more than a tenth of a drop, the merest fraction of a scruple of acid here, "when you remember you've been a Defense teacher."