I am a self-taught pianist and thought I would pick this piece up relatively easily and quickly, but being self-taught I often run into unknown signs, symbols, and other things like that, that give me trouble. I believe I know the sideways S to be a turn, but it is placed above an X-like symbol and this leaves me confused. Any help would be appreciated.
the x stands for a double sharp (instead of ##)
Turn: (look example 4 of the picture below)
now the ornament (turn) behind the quarter above the x - look at the fingering - will be played at the second eight of the note A and 4312 means that you play after A# an eight note length
the the turn B-A♯-Gx-A♯
1=Gx or G## which is the same key as A