February 1998 page 46
Karlheinz Schaldach

A Plea for a New Look at Roman Portable Dials

Argues for re-evaluation of Roman portable dials: forms, readings and classification, urging fresh analysis of surviving pieces and their interpretation.
Dials: Portable, Historical Dials

October 1998 page 44
Karlheinz Schaldach

Cross-Beam Ciphers

This article investigates the history and interpretation of cross-beam ciphers found on medieval sundials and calendars across Northern and Central Europe. It challenges previous terminologies like 'carpenter's numerals' and 'Styrian ciphers', proposing a new theory that these ciphers originated from condensed counting frames (abaci) used for financial calculations.
Historical Dials, Sundial Design & Layout

October 1996 page 32
Karlheinz Schaldach

Vertical Dials of the 5th-15th Centuries

A scholarly examination of vertical sundials from the early medieval to late medieval periods, including typologies, geographic distribution, and functional evolution.
Dials: Vertical, Historical Dials