One of the aspects readers of Magic Under Glass seem to often be enthralled by is the clockwork man, or automaton, Erris, who comes to life. There are other books with clockwork people coming to life, more of them adult than YA/children's, although I imagine we'll see more, as the steampunk trend is far from over.
I would not call Magic Under Glass true steampunk, though. It doesn't take place in a world where steam power is widely used, there is none of the action-packed gadgetry that usually characterizes steampunk; no airships, no one sporting goggles. It doesn't have technology outside of the real 19th century as we knew it. The automaton Erris is inspired, largely, on an automaton by Jaquet-Droz called "The Musician", constructed in the 18th century. (Originally, I intended the automaton Erris to be much older, which is why he is dressed in 18th century clothes. I later decided fairies could still be wearing 18th century clothes anyway...fairies wearing dour Victorian suits just doesn't seem to match!)
Automata have been constructed and discussed since ancient times--the ancient Greeks were said to have made moving statues--but they really became popular during the Age of Enlightenment. "The Musician" was a lady seated at an organ, displayed in the court of Marie-Antoinette and Louis XVI. Her chest moves as if she is breathing, and her eyes follow the keys and look up to the audience. Her motions are very similar to Erris's as he plays. Another famous automaton was a duck, which appeared to eat and digest food and produce feces, although of course the feces was really pre-made and stored within the duck. Kind of like an 18th century "Baby Alive" doll.
While France is known for is 18th century automata, there were also automata called "Karakuri" in Japan around the same time, which are also very beautiful. The seed of Magic Under Glass was actually planted by an exhibit I saw of these automata at the Morikami Museum in south Florida. These were small, graceful automaton that evoked (and influenced) Japanese theater traditions like Noh and Kabuki...although, alas, they didn't show any moving at the exhibit.
One famous automaton that inspired Magic Under Glass was "The Turk", which was actually a magnificent hoax. The Turk was a chess-playing automaton that wore a turban and robes, sitting at a cabinet with his chessboard. He played a strong game of Chess against any human opponent, which naturally perplexed (and no doubt, often creeped out) the Austrian court where it was first displayed, and many more people afterward. It was a long time before the full extent of the mystery was revealed. (There was a man inside the automaton, playing the chess game, but if you're curious about the details, I recommend reading the very enjoyable The Turk: The Life and Times of the Famous Eighteenth-Century Chess-Playing Machine by Tom Standage.)
Magic Under Glass came from the question: what if the chess-playing automaton had not been a hoax? What if he could really think, and how would that be possible? The answer, of course, must be magic.
http://www.karakuri.info (Japanese automata)
The now defunct automates-anciens site. (Weep! This was such a great site!)
The Turk: The Life and Times of the Famous Eighteenth-Century Chess-Playing Machine by Tom Standage. Walker, 2002.