Scratched or incised dials found on the walls of many old churches in England and Normandy, having only a few lines and no figures. They are said to have been used mainly to tell the time of Mass because of the clearly marked line indicating Terce, or 9 a.m., the hour of the principal Mass.
- “Mass dials”. . CatholicSaints.Info. 19 August 2010. Web. 19 February 2017. <http://catholicsaints.info/mass-dials/>