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From Chapter 6: Talons and Tea Leaves
Silvanus Kettleburn was the Care of Magical Creatures teacher at Hogwarts until Harry’s third year, when he was replaced by Rubeus Hagrid.
Kettleburn was an enthusiastic and occasionally reckless man whose great love of the often dangerous creatures he studied and looked after led to serious injuries to himself and, occasionally, others. This fact led to no fewer than sixty-two periods of probation during his time of employment at the school (a record that still stands). Like Hagrid after him, he was prone to underestimating the risks involved in caring for creatures such as Occamys, Grindylows and Fire Crabs, and once famously caused the Great Hall to catch fire after enchanting an Ashwinder to play the Worm in a play of ‘The Fountain of Fair Fortune’.
Kettleburn was a loveable if eccentric man and his continuing employment at the school was evidence of the great affection in which staff and students held him. He finished his career with only one arm and half a leg. Albus Dumbledore presented him with a full set of enchanted wooden limbs on his retirement, a gift that had to be replaced regularly since, because Kettleburn’s habit of visiting dragon sanctuaries in his spare time meant that his prosthetics were frequently set on fire.