Ostomachion (Armstrong, Peter McKenzie)




MP3 file (audio)
Peter M. Armstr... (2013/2/22)

Performer Pages Peter McKenzie Armstrong (creator)
Publisher Info. Edition Ottaviano Petrucci
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Sheet Music


PDF typeset by Unknown
Peter M. Armstr... (2013/2/22)

PDF typeset by Unknown
Peter M. Armstr... (2013/2/22)

Publisher. Info. Edition Ottaviano Petrucci
Misc. Notes Engraved with LilyPond 2.18.2. Request Licenses from ASCAP
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General Information

Work Title Ostomachion
Alternative. Title Wind Chimes from Archimedes' Box
Composer Armstrong, Peter McKenzie
I-Catalogue NumberI-Cat. No. IPA 22
Movements/SectionsMov'ts/Sec's 3 sections
Year/Date of CompositionY/D of Comp. 2013
Average DurationAvg. Duration 10 minutes
Composer Time PeriodComp. Period Modern
Piece Style Modern
Instrumentation 12 MIDI instruments

Misc. Comments

Notes for the Catalog

Ostomachion ("Bone Fight") is an ancient fit-the-pieces-back-into-their-box puzzle and the
subject of Archimedes' monograph of this name, history's earliest treatise on combinatorics.
The puzzle consists of fourteen 3-to-5-sided flat pieces, which can without gaps or overlaps
fill their square box in, all-told, 17152 ways, reducing -- if we discount rotations, reflections
and a few duplicating anomalies -- to 268. These, taken as the fixed content of four "core
triangles" subdividing the square, group finally into 24 "tessellation families", whose lead
items comprise the puzzle's "core squares". (See references below.)

All the tessellations are plotted on a 12-by-12 grid of subsquares via points forming its inner
squares' corners. Thus, horizontally and vertically, points are disbursed along 13 parallel
equidistant levels.

As 13 levels apply as well to inclusive chromatic octave subdivision, these tessellations
seemed to invite musical realization of some sort. Taking the "cores" as my subject matter,
I first converted their X/Y specs to LilyPond score files, separately for each of: the individual
pieces; their intermediate triangular groupings; the full (triangles combined) squares. Each
file of the first two types details all forms (rotations/reflections) and positions that its object
assumes throughout the 24 square tessellations.

With these files I assembled -- to aid me in the composition process, whatever that might
consist of -- a Catalog, here offered for anyone interested in the analysis.

A word about "Odd Man Out!" on page 43. This tessellation, Cutler series #164 and my
favorite, is not among "the 24". It is, however, unique, in containing none of the core triangles
AND not honoring the line that bisects nearly all of the original 268 squares. It is also, finally,
not to be found in my composition (see Score) -- being, as I said, "out".

For anything I have gleaned of Ostomachion history and theory as well as its specifications,
I am indebted principally to three sources: Netz, R., Noel, W. (2007) The Archimedes Codex,
Da Capo Press; http://math.ucsd.edu/~fan/stomach; http://4umi.com/play/stomachion.

Notes for the Score

I have reordered the 24 tessellation scores so as to pair them as variously as possible: the
odd numbers ascending as originally, with the evens interlaced and descending. Interlaced
in turn, externally separating the pairs, are uniquely positioned isolate puzzle pieces.

The puzzle's intermediate "triangle" groupings are realized (not separately, but) as instru-
mental and rhythmic subsets of the full-square tessellations. I.e., each triangle's several
voices share a single instrument (so, 4 per square) and sync rhythmically per their original

But the timing between triangles I have made variable, shifting these apart: increasingly,
through odd-numbered tessellations; decreasingly, through the even-numbered. Altogether,
only two full-square instances actually do fit together: the first and last. Their pair-partners
are the most out-of-whack, with intervening pairs variously so and the center ones about

Random choices (of order, possibly also selection) have played a part, as I wanted an
impression of "wind chimes" (unscripted, one presumes) overall: within range constraints,
instruments and volume levels are randomly assigned. Some choices made "instead" by
design have the intent to appear random: a tempo scheme, and the progression of
subgroup-shifting silences.

All of the above I embodied in a program that (calculating via J, template editing via sed,
scoring via LilyPond and page assembling via pdfjam) generated this listening Score, and
has others, complete as is. (Note: its accidentals apply once only.) The output audios --
71 MIDI files -- I combined via Rosegarden, then converted via TiMidity to WAV and via
pacpl to MP3.

My grandmother's wind chimes enjoyed a breeze far less often than not. Accordingly, this
piece's main character is its silence. I recommend to the listener low volume and a wan-
dering mind.