Much of the following comes from research done by John Martin (indicated in text) - I have added to it where I can. As the principal males are nearly all called William, I have numbered them.
William (1) born 1803
William (2) bapt. 1835
William (3) born 1868
William (4) born 1889
In 1803, at 3,Tavistock Cottages, Roborough, Plymouth, Devon a child was born to Richard and Maria Martin (source: John Martin). The Batter Street Presbyterian Plymouth records show a William Martin (1), son of Richard and Maria, being born on the 24th March of that year, and baptised on 29th April (www.familysearch.org)
At least 3 children were born before William, on an almost yearly basis, and at least 3 were born after him: Maria (1799), Richard (1800), Elizabeth (1802), Mary Ann (1804), Jane (1806) and Harriett (1808) (www.familysearch.org)
At the time of the 1841 census, a Richard and Maria Martin are living Tavistock Road, Charles the Martyr sub district, Plymouth, with a number of younger Martins who may or may not be their children (the 1841 census does not specify relationships). Richard and Maria are both circa 60 (the census also rounds down ages); Maria is 35, Sarah and Robert are both circa 25, Jane Ann and Julia are both circa 20. All were born in Devon.
It seems likely that this is the same Richard who is a 74 year old widower in 1851, living in the parish of St Charles the Martyr with his unmarried daughters Jane and Julia, 27 and 25 respectively.
1841 census HO107, Piece 271, Civil Parish Charles The Martyr, County Devon, Enumeration District 2, Folio 5, p5
1851 census HO107. Piece 1878, Folio 550, p29
None of these children match the baptismal records quoted above, and family tradition has it that both Richard and Maria had died by this time. Believed to have been originally from France, the story goes that both were returned there for burial (source: John Martin).
By 1835 William (1) may have been in Ashburton, married to Elizabeth. On 7th January a William Martin was baptized to William and Elizabeth, but the father is said to be a butcher. All other references to William (1) describe him as an ag lab (agricultural labourer) or farm labourer.
In 1841 William (1) and Elizabeth are living with 6 year old William (2), Emma and Jane. William is an ag lab (agricultural labourer).
1841 census HO107, Piece 253, Civil Parish Ashburton, County Devon, Enumeration District 10, Folio 13, p20
The 1851 census shows the Ashburton William as a farm labourer, with wife Elizabeth and children Emma, Jane, Eliza and Elizabeth. William says he was born in Plymouth.
Emma, Edith and Sarah are shown with their parents on the 1861 census (http://www.freecen.org.uk/) William (1) is an ag lab and the family live in North Street. Elizabeth (maiden name also Martin) was born in Ashburton, and worked as a laundress.
Elizabeth's maiden name confirmed from the birth references to her children on https://www.gro.gov.uk
A William Martin married an Elizabeth Martin at Tormoham on Sept 12th 1834 https://familysearch.org
Moving forward to the September quarter of 1863, an Elizabeth Jane Martin Spry was born in the Totnes district of Devon http://www.freebmd.org.uk/, and a William Martin Spry (3) was born in the Newton Abbot district September quarter 1868. There is little doubt that these are the children of William Martin (2) and Sarah J Spry, because they married in the Newton Abbot district during the June quarter 1872*
* And are living as man and wife in Ashburton on the 1871 census http://ancestry.co.uk
On the 1881 census both William (2) and Sarah J are in Cad Lane, Ashburton, with 5 children including Elizabeth Jane and 12 year old William (3). William (2) is a general labourer.
On the night of the 1891 census, http://www.freecen.org.uk/ only William (3) and one of his brothers is with their parents. William (3) is a general labourer, as is his father.
The Martin family are still in Cad Lane, but not too far away at Great Bridge is another family, headed by a widow named Mary J Pascoe. She is a wool weaver from Cornwall, and on census night her unmarried sister, Sarah A Found is staying with her. Mary J has 3 children, two of them born in Yorkshire. But the youngest, William, aged 1, was born in Ashburton.
Looking at the FreeBMD records, William Martin Pascoe (4) was born in the Newton Abbot district during the December quarter of 1889. But William Martin (3) did not marry Mary Jane Pascoe until after the census in 1891 (in the Newton Abbot registration district June quarter 1891 http://www.freebmd.org.uk/)
William Martin (3) is living with his wife Mary J. at Crockaton in the 1901 census. Also in the household are William (4) aged 11, John aged 9, Lily, 5 and James aged 1.
1901 census RG13; Piece: 2053; Folio: 29; p 23
William Martin (4) married Beatrice Dorothy Bray on the 4th October 1913 at Devonport. Beatrice Dorothy Bray had been born 25th May 1892 in Buckfast, Devon (source: John Martin).
William Martin (4) had a long and eventful life. He joined the army before World War I, and worked his way up the ranks to warrant officer. He was recommended for the Distinguished Conduct Medal 5 times, and served in many of the major battles of the 1914-18 conflict - the Somme, Hill 60 and Ypres.
Returning to Ashburton, he became a publican, running, with his wife, the Royal Oak, then the London Hotel and finally the Rising Sun at Woodland, where in the 1950s there were only oil lamps to light the bar
William and Beatrice were married for 68 years and had two children - Eileen, and Russell Herbert. William was 92 when he died.
Many thanks to Roy Martin for the above.
Above: William and Beatrice Martin, 1960's.
Thanks to Christine Lunt for this photograph
Above: Russell Herbert Martin married Rose Byott at Newton Abbot, Devon, 28 August 1946
Thanks to Roy Martin for this photograph
The Pascoe Family
As is shown above, in the 1891 census there was a family at Great Bridge headed by a widow named Mary J Pascoe. She is a wool weaver from Cornwall and she has 3 children, two of them born in Yorkshire. The youngest, William, aged 1, was born in Ashburton (http://www.freecen.org.uk/).
The two elder children are Francis Pascoe, aged 8, and Mary E(lizabeth) Pascoe, aged 6
Mary Elizabeth married a Penwarden (source: Christine Lunt) - probably Herbert J Penwarden, in the Holsworthy district in the September quarter 1911.
Below: Mary Elizabeth Pascoe.
Thanks to Christine Lunt for this photo
Below: believed to be Mary Jane Martin, formerly Pascoe, nee Found, and her mother
Thanks to Christine Lunt for this photo