There is a book about this telegraph system: here is a snippet from a review found in Google Books, using the words 'Anglesey Liverpool Telegraph Faster:
"Faster than the Wind - The Liverpool to Holyhead Telegraph by Frank Large. Occasionally you come across a book devoted ... the story of how a system was devised to signal news of ship arrivals off Point Lynas. on Anglesey, to Liverpool. ..."
I think it was a paperback published on Merseyside a few years ago, but do not have details.
A