Thank you ribbo39 and wentworth13. I had no record of Thomas Bailey & Maria Andrews (parents of John (born 1804) so an additional generation looks likely to have been added to my family line. I will follow the Wilts OPC. I am just beginning to see the vistas that open up when you delve into these things.
My next task is to establish the names of all Thomas & Maria's children. maybe one was Robert. I will then try to follow the lines that have descended from John's siblings. In case it is of use to someone below is a summary of the lineage from John. The line I descend from all stayed fairly local here in southern England. It is very interesting to discover that I may have relatives in Australia, especially as I have visited you a couple of times for five months in total (and, frankly, love the place!).
John m. Ann (Davis?) in the 1820's. They lived in Upavon (1851 census) and had six children: Emma (1828), John (1831), Louisa (1833), Thomas (1835), James (1838) & Hannah (DOB unknown to me).
James m. Alice Sainsbury in 1861 in the Amesbury area. They lived at the marvellous address of 'Pigsty Corner, Over Wallop' (sadly no longer in existence) before moving to Salisbury. They had six children: George (1864), Frank (1870), Kate (1873), Bessy (1878), William John (1879) & Morris (1881).
George m. Martha Alice Spratt in 1891 in the Alderbury area. I have a glass photograph of this redoubtable couple. They met whilst both working at the Laverstoke Asylum, Salisbury. They had the fashionable six children, of which three died in infancy. The surviving three were: Wilfred George (1894), Winefred Mable (1897) & Edward (1902). George was a railway porter and died 'of concussion' at an early age, so the three children were brought up in the Southern Railway Orphanage.
Wilfred & Edward had children of which two at least are still living in southern England and Yorkshire.
Thanks again for your help.