Pedwar ugain o lythyrau, 1800-1876, y rhan fwyaf at Samuel Roberts a'i dad, John Roberts, oddiwrth teulu a ffrindiau. Mae'r gohebwyr yn cynnwys Maria Griffith, 1828, Dorothy Hughes, 1822-1823, Michael Jones, Llanuwchllyn, 1833, David Lewis, Old Hall, 1822-1826, J. W. H. Pritchard, 1823-1827, Thomas Weaver, 1825-1826, Samuel Weston, 1822-1826, a Sarah Yallowley, 1822-1826. = Eighty letters, 1800-1876, mostly addressed to Samuel Roberts and John Roberts, senior, from family and friends. The correspondents include Maria Griffith, 1828, Dorothy Hughes, 1822-1823, Michael Jones, Llanuwchllyn, 1833, David Lewis, Old Hall, 1822-1826, J. W. H. Pritchard, 1823-1827, Thomas Weaver, 1825-1826, Samuel Weston, 1822-1826, and Sarah Yallowley, 1822-1826.
Mae rhai o'r llythyrau yn cynnwys atebion drafft ac arnodiadau eraill gan S.R. Mae nifer yn cynnwys copïau [gan S.R.?] o lythyrau (dyddiedig 1831-1834) gan ei dad (ff. 2 verso, 18 verso, 68 recto-verso, 70, 73, 87 recto-verso, 104 recto-verso, 115, 133 recto-verso). Mae'n debyg i rhain gael eu copïo ar gyfer llyfr S.R., Cofiant y Parch. John Roberts, o Lanbrynmair (Llanelli, 1837) sydd yn cynnwys cyfieithiad Cymraeg o'r rhan fwyaf ohonynt. Mae llythyrau oddiwrth John Roberts i'w frawd George, 1800, 1805, yn nodi genedigaethau S.R. a J.R. = Some of the letters include draft replies and other annotations by S.R. A number contain copies [by S.R.?] of letters (dated 1831-1834) of his father (ff. 2 verso, 18 verso, 68 recto-verso, 70, 73, 87 recto-verso, 104 recto-verso, 115, 133 recto-verso). These were probably copied in preperation for S.R.'s Cofiant y Parch. John Roberts, o Lanbrynmair (Llanelli, 1837) which includes Welsh translations of most of them. Letters from John Roberts to his brother George, 1800, 1805, record the births of S.R. and J.R.