Part of the difficulty resides in the word “key.” By the second half the century—Clementi’s time—the meaning of “key” was approaching its modern sense, as in “the key of B♭ major.” In the first half of the century, “key” could also imply a note in a scale that received some temporary focus, as in “G—the sixth key in the hexachord on B♭.” If we examine a repertory from the first half of the century, we ought to find more of the practices that were not yet “obliterated.”
