Mara Thorson gives his dates as 1806-1895. This is confirmed by his death certificate which says he died on 18.07.1895 aged 89 years 6 months, so born January 1806; Freidrich Nothmann also gives 1806. However as a witness to Rosalie's marriage in June 1875 his age is recorded as 70 years, so born 1804-05.