No other symbol appearing in heraldry is subject to as much variation as the cross Boutell’s Heraldry, J.P. Brooke-Little, Warne, (revised Edition) London 1970, P 47. Mediaeval Europe was a deeply religious and Christian and many of the nobility wanted to show their devotion by adopting the symbol of the cross as part of the arms. Since no two arms could be identical there arose many variants of the cross, typically involving patterning along the edges Understanding Signs & Symbols – Heraldry, S. Oliver & G. Croton, Quantum, London, 2013, P67, or fanciful, decorative endings to the arms of the cross A Complete Guide to Heraldry, A.C. Fox-Davies, Bonanza (re-print of 1909 Edition), New York, 1978, P128. An edge which is decorated like the top of a castle wall is said to be embattled, or sometimes crenelle, from the original French. (In castle building terminology the parts of the wall that stick up are known as merlons, and the resulting gaps as crenels). A whole sub-section of heraldic terminology has sprung up to describe whether these crennellations appear on which edges, whether they line up or alternate, have additional steps or rounded tops. The interested reader is directed to the reference for the full set! A Glossary of Terms used in British Heraldry, J.H. Parker, Oxford, 1894, Entry:Embattled For obvious reasons, use of this decoration is to be associated with castles and fortified towns, an early authority, Guillim suggest also some association with fire, but with out clear reason The Symbolisms of Heraldry, W. Cecil Wade, George Redway, London, 1898 P41. In all, this is one of the more common, and most effective and appropriate of the decorative edges.