Kenneth Oppel 
This Dark Endeavour [EPUB ebook] 
The Apprenticeship of Victor Frankenstein

Victor Frankenstein leads a charmed life. He and his twin brother, Konrad, and their beautiful cousin Elizabeth take lessons at home and spend their spare time fencing and horseback riding. Along with their friend Henry, they have explored all the hidden passageways and secret rooms of the palatial Frankenstein chateau. Except one.The Dark Library contains ancient tomes written in strange languages, and filled with forbidden knowledge. Their father makes them promise never to visit the library again, but when Konrad becomes deathly ill, Victor knows he must find the book that contains the recipe for the legendary Elixir of Life.The elixir needs only three ingredients. But impossible odds, dangerous alchemy and a bitter love triangle threaten their quest at every turn.Victor knows he must not fail. But his success depends on how far he is willing to push the boundaries of nature, science and love-and how much he is willing to sacrifice.