I've enjoyed doing this, and there is now only
one word I cannot fit in. In 23 Down, the clue is
"Engine driver passes over eastern line". The
answer is DIESEL, but where does "driver" come
into it? The clue would still have fitted without
the word "driver" being mentioned. Am I perhaps
unaware of a bit of railway jargon whereby an
engine driver may, indeed, be called a "diesel"?