Gentleman's Magazine, vol. 80 pt 1 (1810), p. 597 — obituary of John Metcalf · The Gentleman's Magazine, June 1810
"At Spofforth, near Knaresborough, aged 94, John Metcalf, commonly called Blind Jack … His descendants are four children, twenty grandchildren, and ninety great and great-great-grandchildren." (contemporary obituary; no day given)