Parish churches used sundials to enable clergymen to judge the times of services and for public use long before clocks were installed in church towers (see historic churches). A few Anglo‐Saxon sundials survive, e.g. at St Gregory, Kildale (Yorkshire). In the Middle Ages ‘scratch dials’ were inscribed on a buttress or wall close to the porch of a parish church. Later sundials were mounted on stone posts in the churchyard. From the 17th to the 19th centuries churchyard and private sundials became increasingly ornate. Many are inscribed with reminders of mortality.