Poseidon from Cape Artemision – The geometry of a Greek
Masterwork / © 1980-2002 by Franz Gnaedinger, Zurich, fg(a)seshat.ch,
fgn(a)bluemail.ch / www.seshat.ch

POSEIDON FROM CAPE ARTEMISION The Geometry of a Greek Masterwork

Poseidon, standing upright
on his left foot, arms raised, balances his body weight with his right leg and
sights over his left hand, aiming a (now missing) trident at a far away target
we can only guess at.
The figure of this Greek god
displays such composure, creates a wonderfully balanced effect, majestically at
rest upon itself. How did the unknown master achieve this effect? First, he
applied the famous contraposto: Poseidon extends his left arm and his right leg
simultaneously, while bending his right arm and his left leg. Second, he used a
principle I call self-reference: stretch out the left arm and you duplicate the
line of the right upper arm; extend the right leg and you reach the left
shoulder via the navel; prolong the left upper thigh and you reach the right
shoulder via the navel again; extend the left lower thigh and you reach the
left shoulder. Third, the figure is held together by a geometry which my
drawings render visible:

A large circle around
the navel and touching the tip of the middle finger of the left hand seizes the
right hand and the heel of the right foot while resting on the ground. The height
of the navel, and therefore the circle's radius, measure 18 large or 72 small
units, and the circle's diameter measures 36 large or 144 small units. Draw an
arc around the nadir of the circle. Its radius will measure 30 large or 120
small units. The arc will brush Poseidon’s head and cross the circle in the
point marked by the tip of the middle finger of the left hand (aiming finger
tip). The height of this point is that of the horizontal arm line and measures
25 large or 100 small units. The height of the figure measures 30 large or 120
small units. The distance between the navel and the height of the arm line
measures 7 large or 28 small units. The aiming fingertip marks the upper
right-hand corner of a pair of right triangles that are correlated by the
equation 30x30 minus 25x25 equals 18x18 minus 7x7 equals 275. The golden
section of the circle's vertical diameter (144 small units) is marked by the
figure’s nipples (height 89 small units) and the glans (height 55 small units).
How long was the former trident in Poseidon's right hand? Take a rod (or paper
roll) and slide it through the opening of the hand. The rod (or paper roll)
will show towards the aiming fingertip. Fix the rod (or paper roll) in such a
position that the hand holds it roughly in the middle. If the rod (or paper
roll) is 15 large units long, the distances from the fingertip to the fore and
hind ends of the rod (or paper roll) will again be in the golden ratio: about
25 and 40 large units.

The wonderful bronze statue was found on the seabed by Cape Artemision at the northern end of the Ionic island of Euboea and is kept in the National Museum of Athens (no. 15161). The height of the figure measures 209 centimeters, corresponding to an Ionic orgyia (fathom) that measured 208.98 cm. 5 large units equal one Ionic pous (foot) measuring 34.83 cm. 30 small units equal one Ionic paechys (cubit) measuring 52.245 cm.15 large or 60 small units equal two Ionic paechei. 30 large or 120 small units equal six podoi or four paechei or one orgyia.

Available on request: geometrical examinations of the Kouros from Tenea, of the Gettys Kouros and of the Kroisos from Anavyssos.