The
four-sided "star" or "pip" has been used to
designate officer rank in the British and
Australian armies for many years.
The only
officer ranks in these two armies that do not
contain
a pip are those of major, lieutenant general and
field marshal. These ranks utilize a crown rather
than pips.
Although some regiments in the
British Army have used their own version of the
pip, the general issue pip and the one used
in the Australian Army is a stylized version of
the very elaborate
star of the Knight Grand Cross of the military
division of the Most Honourable Order of the Bath,
one of Great Britain's four senior orders of
knighthood. (The others being the Order of the
Garter, the Order of the Thistle and the Order of
Saint Patrick.)
The original badge contains the
motto "Tria Juncta in Uno", which means
"Three Joined in One", and refers to the union of
the three kingdoms of the British Isles
(England/Wales, Scotland and Ireland). If you have
an older metal Australian pip, you might be able
to make out the motto.
As far as I can discover, in WW1
there were 2nd lieutenants in the
Australian Army, as one might expect, but in
WW2 there were none, the rank existing in theory
only, as all lieutenants were 1st
lieutenants with two pips. Why this was so, I have
not yet been able to find out. Perhaps someone out
there knows. Share your knowledge with us.