"It's called a Time-Turner ...and I got it from Professor McGonagall on our first day back. I've been using it all year to get to all my lessons. Professor McGonagall made me swear I wouldn't tell anyone. She had to write all sorts of letters to the Ministry of Magic so I could have one. She had to tell them that I was a model student, and that I'd never, ever use it for anything except my studies.... I've been turning it back so I could do hours over again ..."
-- Hermione Granger (PS21)
The Time-Turner is a small silver hourglass worn on a chain around the neck. It is a very powerful and dangerous magical item which literally turns back time for the user, one hour per inversion of the glass, thanks to the Hour-Reversal Charm contained within it (Pm).
- The use of Time-Turners is regulated by hundreds of laws (Pm) and controlled by the Ministry of Magic (PA21).
- Time-Turners are mainly used for mundane matters of time-management because of the catastrophic consequences time travel can have (Pm).
- Hermione Granger used a Time-Turner for the 1992-1993 school year to allow her to take multiple classes at the same time (PA21).
- Hermione and Harry used a Time-Turner to go back three hours in time and rescue Buckbeak and Sirius Black from a terrible fate (PA21).
Hourglass containing One-Hour Reversal Charms
Kept "vanilla" and relatively harmless by the Ministry due to Croaker's Law: "the furthest someone can go back in time without the possibility of serious harm to the traveller or time itself is five hours" (CC2.16, CC4.4).
This is the type Hermione used to repeat class hours in her Third Year, and to rescue Sirius Black and Buckbeak (PA21).
Made of cheap metal, confiscated from Theodore Nott by Aurors and hidden in the Minister for Magic Office (CC1.5)
Limited use to five minutes in the past, after which time it would begin to shake uncontrollably (CC2.7)
Stolen from Minister Hermione Granger's bookcase (CC1.9), and used by Scorpius Malfoy and Albus Potter to try and go back to try and save the life of Cedric Diggory (CC2.7, CC2.20, CC3.8)
Made for Lucius Malfoy, who wished to travel back further than Professor Croaker would allow at the Ministry (CC4.4).
Kept hidden for years by Draco, who knew it would lend credibility to silly rumours that his son Scorpius was the son of Voldemort. However, when Scorpius and Albus seemed to be trapped in the past, Draco brought the Golden Time-Turner to Harry so they could use it to rescue their children (CC4.4). Thanks to the device, Harry, Ginny, Ron, Hermione and Draco along with the boys were able to intercept Delphi, the daughter of Lord Voldemort in Godric's Hollow on the night the Potters were killed in 1981 (CC4.7, CC4.11).
From the Web
What Can Time-Turners Teach Us? by Paige Crawley