WE HEAR A LOT about the 'mysteries' of
ancient operative stonemasons. Did they
really have any that we can prove? The
answer is yes as did most trades and
professions. Remember, in those days
your job was everything. There were no
social benefits if you were out of work; you
and your family starved. If there were any
special skills or tricks of your trade, you
guarded them jealously because you
would invariably have served an
apprenticeship of several years before
you became fully qualified. These were the
real mysteries.
First of all, let me say that the 'mysteries'
word has been blown up out of all
proportion in the masonic field. The word
'mestiere' in Italian means 'trade' or 'craft' 
and the word is similar in French and, most
importantly, Latin. When AngloSaxon ears
heard the word, they immediately equated it
with 'mystery' and as everyone loves a
mystery, a 'great secret' was born!
So what were the secrets of the trade
that the operative masons kept from
cowans? If you were a stonemason, apart
from the skill of preparing stone which
could only be obtained through lots of
experience there were easilyunderstood
tips or secrets which they kept among
themselves as a means of protecting their
trade. Other trades did the same.
If you are creating a building, there were
still are three basic essentials: the
building must be level; perfectly upright; and
square (at the corners, that is). DIY
enthusiasts who build even small structures,
will tell you that if you don't get the corners
really square, the whole building will start to
spiral. Perhaps not much ofa problem with,
say, a garage, but wjthchurch or castle,
some strange shapes can occur.
The Basics
The level is an obvious one. As is the plumb
line. At one time a workman discovered that
if you tie a length of string to a pebble and
hang it, the 'line' it draws in the air will be
perfectly upright.
But a rightangled corner is more
difficult. The operatives would have had a
large, wooden triangular rightangled frame,
from which the stonemasons could work at
each corner. But because wood warps and
wears, the frame had to be checked
regularly. How did they make a rightangled
frame in the first place? And how did they
check it?
It is easy to delineate such a corner on
paper. As R.J. Hollins mentions in volume
two of his A Daily Advancement in Masonic
Knowledge {reviewed in the last issue): With
compasses, you draw a circle. Then draw a
straight line through the middle of the circle
passing through the centre point {which you
will have made with the compasses).
Youthen mark a spot anywhere on the
circumference, and draw two lines from that
point on the circumference, to each end of
the line passing through the centre point.
One of the corners of the triangle in the
circle will be a perfect right angle. Easy!
In fact, some writers have suggested that
this method is the source of the original
'point within a circle'.
Not so Easy
But things are not that simple. It's one thing
to delineate a square on paper, but how do
you transpose that square to the frame
necessary for the corner of a large building;
a frame which should have sides several
metres in length?
The answer, believe it or not, can be
found on every Past Master's collar jewel.
Just below the square, you can see a
curious shape which looks like an odd 'Y'
consisting of three differently sized squares.
This is known in the Craft as Euclid's 47th
Theorem although, to be quite honest, I
think it was first propounded by Pythagoras,
and he probably got it from the Chinese.
I have a (no doubt annoying) habit of
asking Past Masters what that curious 'Y' is;
most of them haven't a clue, and even out
of those who answer "Euclid's 47th
Theorem" (only a halfdozen to date), have
no idea how it works. Which just goes to
show that our masonic education, such as
it is, is dire.
The actual theorem states that 'In every
rightangled triangle, the square on the
hypotenuse is equal to the sum of the
squares on the other two sides', DON'T
PANIC. What this means in English is: that
the longest side of the triangle, squared, is
equal to the squares of the other two sides.
If you think this isn't much help, you can
guess that it didn't much help the medieval
stone masons either. In fact there are
several measurements that will fit this
description; what was needed, was a set of
measurements that the stone masons
could easily remember. Someone,
somewhere, using Euclid's Theorem,
noticed that in one answer, the three sides
of the triangle could be in units of three,
four and five. So the square of the
hypotenuse (five) multiplied by itself is 25.
Then 3x3 is nine and 4x4 is sixteen and
9+ 16 is 25! Thus was born the 'secret' or
mystery of the rule of 345.
This meant that any operative mason,
using any form of unit say the length of
his elbow to the tip of his fingers could
cut three lengths of timber into three, four
and five units, and lay the lengths out as a
triangle. The corner of the three and four,
then, would be a right angle.
This procedure is so simple, that it is
obvious why operative stone masons
would want to keep it secret from prying
eyes. Add to that the stringandpebble for
a vertical line, and other tricks of the trade,
picked up during an apprenticeship, and
the stone mason had a trade at his
fingertips. But the secrets, or tips, could
easily be passed on by word of mouth 
so it is understandable why dire threats
were made, and no doubt carried out, to
anyone who illegally gave the secrets to
someone who had not passed along and
thorough apprenticeship.
What the freemasons have made of
those secrets or mysteries, is another story.
