The morning breeze still carried the damp freshness of the sea when the first golden light broke across the horizon. Before the heat of the beach could settle, Bhāskara was already striding across the packed sand, his cloak swaying to the rhythm of his customary enthusiasm. With a theatrical nod of his head, he invited Tribal and Alaya to accompany him to an isolated stretch of coast, where two solitary palm trees stood like sentinels before the vastness of the waters.
As they approached, the soft morning light revealed singular details in the tall, slightly leaning trunks. The rough bark of the second palm was covered in dozens—perhaps hundreds—of small horizontal notches, made with a sharp blade, arranged in a precise and meticulous sequence.
Alaya stepped forward, adjusting her posture as she observed those scarred grooves in the wood. Her eyes traced the length of the trunk from bottom to top before she faced the astronomer.
"What do these marks mean, Bhāskara?" she asked, her tone balancing sincere curiosity with slight reserve. "They look like the record of an ancient count."
Bhāskara smiled, his eyes gleaming at the question. He approached the tree and placed his fingers on the notches with the reverence of one touching a sacred monument.
"For years, my routine on this beach obeyed a single rite," the sage explained, turning to face them. "Every day, at the exact moment when the Sun reaches its highest point in the sky—solar noon—I observed the smallest shadow cast on the ground by the crown of the first palm. Where the extreme tip of that shadow touched the second tree, I made a small cut in the wood."
He slid his hand along the column of grooves.
"Summer after summer, winter after winter, I watched the shadow rise and fall along the trunk as the angle of light changed. And then, after countless observations, the cycle was complete. I realized that the shadow took exactly three hundred and sixty-five days to return, with absolute precision, to the same starting point."
Bhāskara stepped back, opening his arms before the immensity of the sky and the sunlit beach. His voice resonated firmly, charged with an almost mystical solemnity:
"Men did not create the year. They merely discovered how long the heavens take to repeat their own steps."
Bhāskara bent down and withdrew from his leather satchel a long braided rope, full of knots tied at regular intervals. It was his ancient measuring instrument, the tool he used to measure short distances in the sand.
"If we want to measure the curvature of the world by marching southward," said the astronomer, lifting the rope, "we will need to stretch this cord repeatedly at every step. But the coastal wind and the unevenness of the terrain make the process slow and prone to errors."
Tribal approached, observing the instrument in Bhāskara's hands, and then fixed his gaze on the footprints the sage had just left in the sand.
"There is a greater flaw in the intention of using the cord only with your hands," Tribal pondered, his voice calm and analytical. "If we count only ordinary steps across leagues of walking, fatigue will alter the rhythm. The step at the beginning of the morning will be wider than the step at dusk. The mind will deceive itself in the summation, and the real distance will be lost in the body's weariness."
Bhāskara frowned, assimilating the criticism with seriousness. Alaya, who had been following the conversation a few paces away, crossed her arms, curious to see how they would resolve that dilemma.
Without saying another word, Tribal knelt in the sand. He took a length of the sturdy rope and cut a precise segment. Then, he adjusted one firm end around Bhāskara's left ankle and tied the other end around his right ankle, leaving between them an exact, tensioned length.
Bhāskara took a step forward. As he tried to stretch his leg beyond the limit, the rope tightened, gently interrupting the movement. The opening of each stride became rigorously identical to the one before.
The astronomer took three more steps, feeling the physical constant dictated by that binding. His eyes widened, gleaming with immediate realization.
"Each stride..." Bhāskara murmured, already anticipating the scale of the method. "Each stride will be an immutable unit! I won't need to stop to stretch cords on the ground. I'll simply walk and count the paces!"
Tribal rose to his feet and looked at the sage. A knowing smile appeared on the faces of the two men on the beach. Without fanfare or complex formulas carved in stone, they had just simply resolved the practical doubt that had troubled Bhāskara's mind for years.
Enthusiastic about the new precision of his stride, Bhāskara walked to an open stretch of beach where the sand seemed firm and flat. He raised his arm, pointing at the ground with conviction.
"Here!" declared the astronomer, his voice full of authority. "This is the perfect spot to excavate the basin of the giant sundial. The inclination relative to the horizon is clean, and nothing will obstruct the sunlight at noon."
Tribal approached slowly. Instead of looking at the sky as Bhāskara did, he bent down and pressed his palm against the ground. He observed the moisture that rose slightly between his fingers, the pattern of the small ripples left by the previous tide, and the texture of the grains beneath his feet.
After a few moments of reflection, he rose and said calmly:
"Not here."
Bhāskara stopped mid-motion, frowning with evident bewilderment. To him, that spot satisfied all the geometric requirements he had learned from the tomes and from observing the stars.
"What do you mean 'not here'?" questioned the sage, his pride slightly wounded. "The plane is perfect, Tribal! The view of the celestial vault from this point is impeccable."
"The sky may be perfect, but the earth gives way," replied Tribal, maintaining a firm and serene tone. "The seemingly firm sand of this strip holds the ocean's moisture. When we excavate the basin and mold the clay, the weight of the structure and the invisible infiltration of water will cause the bottom to sink unevenly. In a few weeks, the ground will yield a few millimeters, the central rod will lose its plumb, and all the geometry of your instrument will be destroyed."
A small impasse settled on the beach. Bhāskara mastered the secrets of the heavens, the trajectories of the Sun, and the calculation of time; but Tribal knew matter, the substance of the world, and the physical language of the earth.
The astronomer looked at the sand at his feet, then at Tribal's hands stained with damp earth, assimilating the technical warning. Bhāskara's mathematical rigor overrode the impulse of the moment. Reason conquered pride.
"The earth gives way..." Bhāskara murmured, nodding slowly as a sign of respect. "You are right. A perfectly calibrated instrument for the sky is useless if its foundation falters on the ground."
Without further argument, they turned inland. They walked a few meters above the high-tide line, where the terrain became hard, composed of a firm mixture of limestone rock and packed earth. There, where the ocean did not reach and the foundation would remain immutable, they agreed to set the base of the great endeavor.
With the ideal spot determined, the physical work began without delay. The effort required strong arms and a steady rhythm. With reinforced wooden shovels and leather containers, the three began the excavation under a Sun that rose quickly in the sky.
The initial layer of loose, hot sand proved challenging, slipping back toward the center with every thrust of the shovels. Alaya, with the agility and determination that were her own, took on the task of removing the excess accumulated at the edges, using a wide plank to create a defensive barrier that prevented the dry sand from collapsing into the hole. She worked without complaint, sweat gleaming on her skin as she kept the perimeter clean and safe so the two men could go deeper.
As they advanced, the soil's texture changed. The loose sand gave way to dense clay, mixed with hard, resistant limestone gravel. Each dig became heavier, requiring the full force of the body.
Gradually, the concavity began to emerge from the ground, excavated with the promise of becoming the great sundial.
With every span of earth removed, Tribal interrupted the movement. He would crouch in the cavity, extending a tensioned thread from the center to the edges, rotating it in an arc to check the curvature. He used his own fingers to measure the exact depth and adjust the slope of the walls, scraping away millimeter imperfections with the tip of a flat stone. There was no haste in his gestures; there was an almost sacred rigor in the pursuit of perfect symmetry.
Bhāskara, wiping his brow with his tunic sleeve, leaned on his shovel and observed his partner in the endeavor with undisguised fascination. Accustomed to dealing with the abstraction of numbers and the perfection of star charts, the astronomer saw in Tribal's hands the exact transposition of theoretical geometry into the raw matter of the earth.
"Incredible..." Bhāskara murmured, shaking his head in genuine admiration. "Your perception of space needs no rulers, Tribal. Your gaze reads the curvature as if you see it before you even carve it."
Alaya approached, bringing a bowl of fresh water she had collected from the nearby vegetation. She observed the perfectly round cavity emerging from the ground, then looked at Bhāskara's marveling expression.
"Don't be so surprised, sage," said Alaya, with a knowing half-smile as she handed the water to both of them. "He always sees the forms the earth wants to take before any of us. The work is hard, but with his precision, this ground won't miss the Sun's path."
The Sun finally yielded to the orange and violet hues of twilight. With the basin excavation complete and the shape perfectly aligned, the three decided to stop working. Fatigue weighed on their shoulders, but the satisfaction of the progress made ensured a well-deserved rest.
Seated around a small fire that Alaya had lit near the vegetation, they shared a simple meal of dried grains and coastal fruits. The rhythmic sound of waves breaking on the beach brought a welcoming calm after hours of physical effort.
When night had fully settled, Tribal rose and began walking slowly along the low-tide line, where the water had receded, leaving the sandbank exposed. Every few steps, he would bend down and collect small seashells, calcified fragments, and pieces of coral brought in by the tides. He accumulated them carefully in the fold of his tunic.
Bhāskara, who had been watching Tribal's movements while finishing his meal, furrowed his brow. The astronomer's curiosity, ever alert, overcame his fatigue. He rose and walked over to his partner.
"The day is over, Tribal," said the sage, looking at the handful of shells in his hands. "We've excavated the basin, and the ground is ready for the clay. Why are you collecting these shells now?"
Tribal paused, observing a small nacreous fragment in his palm before tucking it into his tunic. He looked at the dark ocean horizon and replied with his usual serenity:
"The coast itself will provide the stone we need."
Bhāskara blinked, evidently confused. He looked at the sea, at the sand beneath his feet, and again at the broken shells in Tribal's hands.
"Stone?" asked the sage, failing to understand the connection. "There's no hard rock on this beach to line the sundial, and the clay alone will crack under the Sun's intense heat. How will these shells become the stone we need?"
Tribal smiled enigmatically, keeping the secret of the process that would reveal itself the following morning.