Wife of “John Sammals”, originally provided by Sarah Ferguson (nee Churton b.1970) in April 2009 was:
Elizabeth Hearle
Birth: 27 Jun 1821, St Cleer, Cornwall, England
Married John Sammals: Dec 1850, St Germans, Cornwall, England
Death: May 1861, Veryan, Cornwall, England

However, the wife of John was subsequently changed by Sarah Ferguson to:
Elizabeth Hornabrook
Birth: Circa 1810, St. Cleer, Cornwall, England
Married John Sammals: 21 December 1831 in St. Cleer, Cornwall and had ten children together. She also had two children from another relationship.
Death: December 1886 in Liskeard, Cornwall, England

Brian of nzolivers.com has updated the wife of John Sammals to Elizabeth Hornabrook.

Looking at the 1841 England Census for St Cleer, Cornwall, found in June 2018:
John Samels, 30 years of age, Agriculture Labourer [Places year of birth at circa 1811]
Betsey, 30 years [Places year of birth at circa 1811]
Mary, 9 years [Places year of birth at circa 1832]
William, 7 years [Places year of birth at circa 1834]
Jane, 5 years [Places year of birth at circa 1836]
John, 3 years [Places year of birth at circa 1838]
Richard, 4 months [Places year of birth at circa 1841]
William, 65 years, Agriculture Labourer [Places year of birth at circa 1776]

Looking at the 1851 England Census for St Cleer, Cornwall, found in June 2018:
John Samels, Head, 40 years of age, Agriculture Labourer [Places year of birth at circa 1811]
Elizabeth, Wife, 40 years [Places year of birth at circa 1811]
Mary, daughter, 18 years [Places year of birth at circa 1833]
Elizabeth, daughter, 7 years [Places year of birth at circa 1844]
Anna, daughter, 3 years [Places year of birth at circa 1848]
George H, son, 2 years [Places year of birth at circa 1849]

Looking at the 1861 England Census for St Cleer, Cornwall, found in June 2018:
John Sambles, Head, 50 years of age, Copper Miner [Places year of birth at circa 1811]
Elizabeth, Wife, 49 years [Places year of birth at circa 1812]
Elizabeth, daughter, 16 years [Places year of birth at circa 1845]
Hannah, daughter, 14 years [Places year of birth at circa 1847]
George H, son, 11 years [Places year of birth at circa 1850]
Thomas, son, 9 years [Places year of birth at circa 1852]

Looking at the 1871 England Census taken on the night of 2 April 1871 for the Kenwyn Parish, Cornwall, found in June 2018:
Thomas Jones, Head, Married, age 30, Sawyer, Born Kenwyn, Cornwall, England [circa 1841]
Hannah Jones, Wife, age 25, Born St Cleer, Cornwall, England [circa 1846]
Elizabeth Jones, Daughter, age 4, Scholar, Born St Clement, Cornwall, England [circa 1867]
Emma Jones, Daughter, age 3, Scholar, Born St Clement, Cornwall, England [circa 1868]
Hannah Jones, Daughter, age 2, Born Kenwyn, Cornwall, England [circa 1869]
Elizabeth L Sammels, Lodger, Widow, age 60, Born St Cleer, Cornwall, England [circa 1811]

Looking at the 1881 England Census for Liskeard, Cornwall, found in June 2018:
Elizabeth Sammels, Head, 71 years [Places year of birth at circa 1812]