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The Ticking Stone: The Megalithic Second, the Sumerian Cycle, and the Pendulum's
Return
Ian Beardsley, Deep Seek!
Abstract!
This paper proposes a unified theory for the historical development of the second as a
fundamental unit of time. Challenging the linear narrative of metrological progress, we argue for
a model of convergent evolution: the ~1-second interval was independently identified by
Neolithic megalithic builders and the later Western scientific tradition using two distinct
metronomes. We posit that the megalithic builders derived a 'proto-second' from the human
heartbeat, using it to standardize linear measures like the 'Megalithic Yard' for astronomical
construction. Millennia later, Western science, inheriting the Sumerian base-60 system, formally
defined the second based on the Earth's rotation. The pendulum clock of the 17th century is
re-evaluated not as an invention, but as a synthesizing technology that reconciled this ancient,
biological second with the modern, astronomical second through a gravitational standard. This
convergence suggests a deep resonance between human biological rhythms and the physical
constants governing our planet.!
*Keywords:* megalithic astronomy, history of timekeeping, metrology, pendulum, second,
Alexander Thom, Sumerian mathematics!
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1. Introduction: The Anachronism of the Second
The second is the bedrock of modern precision, from fundamental physics to global navigation.
Its current definition, based on the immutable frequency of the cesium-133 atom, crowns a
long scientific journey. Standard historiography places the accurate definition of the second in
the early modern period, following the standardization of length and mass (Landes, 1983). This
narrative presents a logical progression: from tangible measures (the cubit, the grain) to the
abstract quantification of time via the pendulum.!
This paper contends that this linear model obscures a more profound and cyclical history. We
propose that the interval of one second was not a late discovery but a primordial intuition,
identified cross-culturally through different methodologies. We present evidence that Neolithic
megalithic builders of Western Europe may have utilized a 'proto-second' derived from the
human heartbeat, embodying it in their standard measures and monumental astronomy.
Concurrently, though independently, the scribes of Mesopotamia developed the mathematical
framework for dividing time into seconds based on the Earth's rotation—a legacy perfected in
the *Almagest* and transmitted to the modern world.!
The invention of the pendulum clock, rather than being a pure genesis, thus emerges as a
grand synthesis. It was the moment the intrinsic, biological second was harmonized with the
extrinsic, cosmic second through the universal constant of gravity. The convergence of these
two independent paths of discovery on the same temporal unit suggests that the history of
timekeeping is not merely one of technological advancement, but a deepening recognition of a
fundamental rhythm connecting human physiology to celestial mechanics.!
2. Literature Review
This thesis sits at the intersection of archaeoastronomy, metrology, and the history of science.
The foundational work of Alexander Thom (1955, 1967) proposed the existence of a
standardized 'Megalithic Yard' (MY ≈ 2.72 ft) used in Neolithic Britain. While his statistical
methods and the universality of the MY have been debated (Ruggles, 1999), his assertion of
sophisticated prehistoric astronomy is widely accepted (Hoyle, 1966; Hawkins, 1965). Our
paper engages with this tradition but introduces a novel hypothesis: that the MY was not an
arbitrary length but one derived from a heartbeat-paced tempo.!
The standard history of timekeeping is masterfully chronicled by Landes (1983), who details the
evolution from water clocks to the pivotal invention of Huygens' pendulum clock (Huygens,
1673). The role of this invention in enabling the Scientific Revolution is undisputed (Grafton,
2023). The deep historical roots of our time system in Babylonian base-60 mathematics are
thoroughly documented by Neugebauer (1957), with its transmission through Greco-Roman
(Ptolemy, c. 150 AD) and Islamic astronomy (Al-Biruni, c. 1030 AD) forming a clear lineage. Our
work seeks to bridge the often-separated narratives of prehistoric metrology and classical
mathematical astronomy, arguing they represent two expressions of the same fundamental
temporal understanding.!
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3. The Primordial Metronome: Heartbeat, Pace, and Stone
The most universally accessible timekeeper for any human is their own body. A resting human
heart rate of approximately 60-70 beats per minute provides a natural, intuitive metronome for
a 0.85-1.0 second interval. We propose that Neolithic builders used this rhythm not to count
seconds abstractly, but to standardize linear measure through pace. A consistent pace, set by
the heartbeat, creates a standard length over distance.!
This theory finds its strongest support in the work of Alexander Thom. The Megalithic Yard (MY
≈ 0.829m) produces a pendulum with a half-period of 0.915 seconds (one swing left, or right)—
strikingly close to the interval between heartbeats at a resting pulse of 65-70 bpm (0.86-0.92
seconds). This alignment suggests the MY may have been derived from, or resonated with, the
human body's natural rhythm. A builder could have walked, marking a unit with each heartbeat,
to create a reproducible standard. This 'heartbeat yard' would then be the module used to
construct the monumental stone circles surveyed by Thom.!
These structures, such as Stonehenge, were not merely calendars but precise astronomical
instruments. The use of a standardized measure, derived from a temporal rhythm, allowed for
the accurate alignment of stones to solstitial sunrises and lunar extremes (Ruggles, 1999). The
megalithic builders thus translated their internal, biological sense of time into an external,
architectural language for measuring celestial time. The second, in this context, was not a
number but a rhythm embedded in the very fabric of their metrology and astronomy.!
4. The Cosmic Metronome: From Base-60 to the Rotating Earth
Parallel to this intuitive development, the civilizations of Mesopotamia were building a
mathematical framework for time. The Sumerians and Babylonians developed a base-60
(sexagesimal) numeral system that was uniquely suited for astronomy and division
(Neugebauer, 1957). They divided the circle into 360 degrees and the day into 24 hours, laying
the groundwork for smaller units.!
This knowledge was inherited and refined by Greek astronomers. Ptolemy's *Almagest* (c. 150
AD) represents the pinnacle of this geocentric tradition, a complex mathematical system
capable of predicting planetary positions with remarkable accuracy. Crucially, the theoretical
division of the hour into 60 minutes and the minute into 60 'second small parts' (*partes
minutae secundae*) was established, though it remained a calculation tool, not a measurable
unit.!
A revolutionary insight emerged with the Indian astronomer Aryabhata (c. 476–550 AD), who
explicitly proposed a rotating Earth as the cause of the apparent diurnal motion of the stars
(Kak, 2000). This was the conceptual key: identifying the Earth itself as the central timekeeping
mechanism. The Islamic scholar Al-Biruni (c. 973–1050 AD), who knew of Aryabhata's work,
represented the synthesis of these traditions. He used Babylonian data, Greek geometry, and
Indian ideas to compute the Earth's circumference with stunning accuracy. Yet, he could not
accept the rotating Earth, as the physics of inertia and gravity needed to explain why we are
not flung off was a millennium away. The second was now a defined mathematical concept,
but its physical basis remained unresolved.!
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5. The Synthesis: The Pendulum's Return and the Unification of Time
The early modern period created the conditions for a synthesis. The need for precise
timekeeping for navigation and science demanded a new standard. The breakthrough came
with Galileo's discovery of the isochronism of the pendulum and its practical application by
Christiaan Huygens in 1656.!
Huygens' pendulum clock did not invent the second; it gave it a physical, reproducible
embodiment. The length of a pendulum that beats seconds (2-second full period) is determined
by the gravitational constant (g). By creating a device whose period was governed by a
universal physical law, Huygens bridged the gap between the two historical paths. It connected
a **length standard** (the pendulum rod) to a **time standard** (the second). It reconciled the
**astronomical second** (1/86,400 of a day) with a precise, mechanical counterpart. Its
rhythmic tick directly mirrored the **biological second** of the human heartbeat, making it an
intuitively natural unit.!
This was the return of the megalithic principle, now elevated by the laws of physics. The
pendulum was the technological proof that the rhythm the megalithic builders felt in their
pulses was the same rhythm that governed the falling of a weight, a rhythm ultimately derived
from the mass of the Earth itself.!
6. Discussion: Implications of Convergent Temporal Perception
The independent convergence on a ~1-second interval is unlikely to be mere coincidence. It
suggests this timescale is a 'Goldilocks unit' for human cognition and interaction with the world
—slow enough to be perceived, fast enough for complex motor tasks and parsing the stream
of consciousness.!
This forces a re-framing of the history of metrology. It is not a simple linear progression but a
spiral, where an intuitive, embodied knowledge was later formalized and universalized through
mathematics and mechanics. The megalithic builders were the first astronomers to embody
time in space; the pendulum clockmakers completed the circle by using space (a length) to
define time with unprecedented accuracy, unlocking the Newtonian synthesis.!
7. Conclusion
The journey of the second reveals a profound unity in human inquiry. From the solstice-aligned
stones of Stonehenge, laid out with a measure born of a heartbeat, to the ticking pendulum in
Huygens' workshop, governed by the force of gravity, humanity was slowly deciphering the
same cosmic code. The second was always there, ticking in the human chest and in the spin of
the Earth. The history of its measurement is the story of us recognizing that connection. This
convergent discovery invites further interdisciplinary study, from computational models of
megalithic construction to neuroscientific investigations of human temporal perception, to
further unravel the deep bonds between life, time, and the cosmos.!
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References
Grafton, A. (2023). *The Scientific Revolution: A Very Short Introduction*. Oxford University
Press.!
Hawkins, G. S. (1965). *Stonehenge Decoded*. Doubleday.!
Hoyle, F. (1966). Stonehenge: An Neolithic Computer. *Nature*, 211(5048), 454-456.!
Huygens, C. (1673). *Horologium Oscillatorium*. Paris.!
Kak, S. (2000). The Astronomical Code of the Ṛgveda. *Indian Journal of History of Science*,
35, 1-20.!
Landes, D. S. (1983). *Revolution in Time: Clocks and the Making of the Modern World*.
Harvard University Press.!
Neugebauer, O. (1957). *The Exact Sciences in Antiquity*. Brown University Press.!
Ruggles, C. L. N. (1999). *Astronomy in Prehistoric Britain and Ireland*. Yale University Press.!
Thom, A. (1955). A Statistical Examination of the Megalithic Sites in Britain. *Journal of the
Royal Statistical Society*, 118(3), 275-295.!
Thom, A. (1967). *Megalithic Sites in Britain*. Oxford University Press.
