Dear Peter, I have been trying to go back beyond 1837 with parish registers.The nearest church to Hilbre Island is St Bridget's West Kirby.This is what I found there:
February 7th 1841.William Henry, son of Thomas and Elizabeth Mathews.Hilbre Island.Superintendent of the Telegraph. April 28th 1842.Elizabeth, daughter of Thomas and Elizabeth Matthews.Hilbre Island.Superintendent of the Telegraph. I started at 1823 and went through to 1841, but didn't find any more Mathews or Mathias baptisms.
Today, we went to Birkenhead Central Library and looked at the Parish Registers for Hoylake Holy Trinity.This was a new church and the registers only started in 1834.This is what we found: August 6th 1837.John, son of William and Marianne Matthias.Helbray Isle.Keeper of the Telegraph. January 6th 1839.Thomas, son of Thomas and Elizabeth Matthews.Hilbre Island.Mariner.
I still don't know whether William and Thomas Mathews (parents) were brothers and I still haven't found the birth of William Mathias, born c.1835.However, what does seem certain is that John was the younger brother of William and therefore this is the proof you need to establish the connection between William and John. Regards, Diane.