by Ken Alder
This drawing by Méchain shows the position of the reflecting mirror he placed in front of the portico of the small chapel of Notre Dame, on a pinnacle of rock high above the monastery of Montserrat in Catalonia. (From the Archives de l’Observatoire de Paris)
During his six months in Spain he had measured five coastal triangles, but he had yet to learn whether his mission was feasible. The evidence so far was discouraging. Success depended on measuring a giant triangle across the straits to his arc’s final anchor, the southern island of Ibiza. Tightrope-walking his way up and down the Catalan coastline, Méchain had strained to catch sight of the island with all the telescopic power at his disposal. His Spanish hosts had sworn that from the summit of Montsia he would be able to see Ibiza as clear as daylight, but so far neither he nor Captain Enrile had been able to make it out through the autumn mist and rains. The Spaniards, Méchain feared, had lied to him.
The time had come to cross over to the islands, reverse perspective, and see for himself whether the coastal range was visible from there. The French ambassador in Madrid had finally procured him a passport. But no sooner had the Prueba pulled into Barcelona harbor to ferry her captain and learned passenger across the straits than half the crew died of yellow fever. Terrified, the port authorities ordered the ghost ship to sail for quarantine—with Enrile courageously volunteering to resume command of his contaminated vessel. Méchain begged his friend not to go, and instead to remain with him in Barcelona “where he could be useful to me.” Enrile insisted that his duty lay with his vessel and the remnants of his crew.
To the south, Andalusia was infested with yellow fever. Three hundred people a day were dying in Málaga alone, and the zone of infection was spreading. Rumor and panic surged up the coast. Barcelona’s wealthier citizens fled to the countryside before the city was sealed shut. The French government deployed a cordon of troops along the frontier to prevent any incursion of the disease. Stuck in Barcelona—lodged once again in the Fontana de Oro—his six-month supply of funds exhausted, Méchain’s courage began to fail him.
It was like a nightmare. On a December evening a decade earlier, from the tower at Mont-Jouy, he had sighted a signal flare on the island of Mallorca. Then war and injury had snuffed out his ambitions. Now war and disease threatened to cut him off again, while his hand-picked team deserted him. Three days after the team returned to Barcelona, Le Chevalier, Méchain’s former student, lit out for southern Spain in search of classical antiquities. Then Chaix left too, returning to the safety of Madrid. It was not just out of fear of disease. Both men complained that Méchain would not let them even look through the repeating circle.
Méchain had never understood the art of leadership: when to share responsibility, as well as when to assume it. For him, the quest for precision was like a voyage through purgatory, with each savant answering for his own sins. And Méchain was too absorbed in his own self-criticism to let others shine. He showed no tolerance for even their most trivial mistakes. When he opened a case of poorly packed reflectors, it was enough to convince him that he had erred, even that once, in trusting others. The ulcerating question, of course, was whether he could trust himself.
To whom could he turn in this moment of self-doubt? To none other than the man he most resented, his one-time partner, Jean-Baptiste-Joseph Delambre. A series of plaintive letters, as pathetic as any he had ever written, spilled from his pen. The winter was cold and the Spanish had no notion of indoor heating. What should he do? Which plan should he adopt? Might the Bureau of Longitudes supply him with additional funds? He even offered to return to Paris if the Bureau thought his “feeble lights” could be better employed in the capital. “This is truthfully and sincerely my current situation, my dear colleague, and I tell you all this without complaint. . . .”
It was as if nothing had changed, nothing had been learned. His son and the loyal Dezauche would stick with him to the end. To replace his renegade assistants he enlisted the aid of a Trinitarian monk named Agustín Canellas, a self-proclaimed astronomer, confident of his worth and eager for a role in a historic expedition. More valuable was the support of a local grandee, the Barón de la Puebla, an amateur astronomer from Valencia. The baron assured Méchain that Ibiza would be visible from the coastal mountain of Desierto de las Palmas, south of Montsia in the province of Valencia; and better yet, he offered to establish a signal on its peak while Méchain observed from the islands.
Finally, in early January 1804, Méchain arranged passage to Ibiza for himself and his son on the Hypomene, a Spanish frigate named after the youth in Greek mythology who dropped distracting golden apples as he raced the swift Atalanta. No such swift passage ensued. Méchain’s bad luck at sea held. A simple one-day crossing became a three-day torture of calms, contrary winds, and high seas. Unable to enter the main port at Ibiza Town, the Hypomene swung east around the island to a cove off Punto Grosa. Yet no sooner had they dropped anchor than a troop of armed islanders assembled on the shore to deny them landing. They would not even deliver a letter, for fear it would spread yellow fever. The ship had only two days of provisions remaining on board. Food and water were running low. Every effort to sail out of the cove failed. The Hypomene’s captain pleaded with the islanders to convey their situation to the governor, across the island. Two days passed before a response was shouted back: the crew might cut wood and collect water in an isolated spot while the governor looked over the mission’s official papers. These were duly transmitted, after first being carefully doused in vinegar. Reassured that the travelers were free of infection, the governor sent word that Méchain and one naval officer might search out a suitable station on the island.
About half the size of Oahu, Ibiza today is an “international resort destination.” Originally settled by Phoenicians, Ibiza Town wraps around its conical hillside like a white Moorish turban, the eyes of its cubical houses turned south toward Africa. The interior of the island is mountainous and was then sparsely populated. Poverty existed side by side with Edenic fertility: figs, almonds, grapes, melons, and olives grew in abundance. Palms fringed the coast, and pine trees covered the rugged hillsides. But Méchain’s unlucky star had followed him onto this island paradise. Ascending a rocky trail to the peak of Los Masons, he fell off his mule, injuring his head and spraining his wrist. He refused to call a halt. “It was nothing . . . ,” he wrote to Dezauche, still in Barcelona, “and you may laugh over it at the table of the Fontana de Oro, or wherever else you wish.” Worse than any physical injury, however, was the disappointment that awaited him on the top of Los Masons. He had been told the peak afforded the best view of the mainland coast, and indeed he could see a range of mountains to the west, as well as the big island of Mallorca to the north. Unfortunately, he could not make out the peak of Montsia, the southernmost station in his chain of completed triangles. The Spaniards had indeed lied. “I thumb my nose at them,” he wrote. This left him with two alternatives, each of which presented its own complications. He could return to the coast to extend his mainland triangle chain south into Valencia before triangulating across the straits to Ibiza—although this would mean that his chain would temporarily veer far west of the meridian. Or he could build his chain of triangles by island hopping: triangulating from Barcelona to Ibiza via Mallorca—although this would mean measuring several giant triangles as well as a baseline on Mallorca. Either way, the season for latitude measurements was ending and his budget was almost spent.
Not only that, but when he viewed the entire circumference of Ibiza from the top of Los Masons, his heart sank still further. He could not locate the Hypomene. The ship was no longer in its cove off Punto Grosa, nor had it docked in the main port at Ibiza Town. The boat had vanished, along with his son and his instruments. It was enough to make a savant curse his fate. He prepared himself for the eventuality that “my last leave-taking from my family and friends was my eternal adieu.”
Again he wrote to Delambre. Might his colleague recommend a course of action? What did t
he Bureau of Longitudes think of his two alternatives? Would the island-hopping scheme succeed? Would the westward deviation along the coast distort the results? And while he was at it, might he vent his frustration? “Hell and all the plagues it spews upon the earth—storms, wars, pestilence and dark intrigues—have been unleashed against me. What demon still awaits me? But vain exhortation will solve nothing, nor complete my task.”
The Hypomene, he soon learned in Ibiza Town, had sailed to Mallorca for provisions. So while he waited for a response from Paris, he likewise booked himself a passage across to the big island. On January 27, 1804, he sailed into Palma, Mallorca’s capital, a busy port town of 30,000 inhabitants, dominated by a hulking ivory-hued cathedral. He spent nearly two months—reunited with his son—on Mallorca, an island known since Roman times as “the fortunate isle.”
Mallorca was more populous than Ibiza, and four times its size. Its northern mountains reached an elevation of five thousand feet, and were covered with snow when Méchain arrived in the winter of 1804. Yet beneath the white peaks its plains were tropical, with groves of oranges, almonds, palms, dates, figs, carob, and plantain. Ruined temples lay scattered across the island. In the twelfth century the Balearic Islands had governed a continental kingdom that included Catalonia and much of southern France. The local Catalan dialect embodied millennia of exchange and conquest, with phrases from Syriac, Greek, Latin, Vandal, Arabic, and Castilian.
It was indeed an enchanted isle, a refuge from time’s march. The town of Palma was ruled by a mechanical “sun clock,” which rang from the Gothic town hall. Legend had it that the sun clock had been brought to the island by Jews from Jerusalem. More probably, the fabled instrument was installed by fourteenth-century Dominicans. The clock divided each day into twelve hours, but hours which lengthened proportionately as the summer days lingered and shrank proportionately as wintry darkness shortened the daylight. Eighteenth-century commentators considered the clock unsuitable for rational administration, but they admitted that the people of Palma found that its bells helped them to regulate the watering of their sumptuous gardens. Standardization lies in the eyes of the practitioner. Sadly, a few decades after Méchain’s visit, the sun clock vanished as mysteriously as it had come.
While he waited for the mountain snows to melt, Méchain conducted astronomical observations in Palma with his son, including a viewing of a dramatic solar eclipse. Not until March did he set out across the island for the north-coast town of Sóller in a fertile valley of orange groves. From there, Méchain and his party—his son, Captain Enrile, and a band of sailors—rode mules as far as the last manor house, then climbed on foot to the peak of Silla de Torrellas. The path was steep, rising nearly one mile in altitude within two miles of the coast. The lower slopes were planted with olive trees, gnarled and shaped by centuries of wind and pruners’ knives, and ringed by stones to ward off erosion. Further up, the pine forests had been logged to build ships for the Spanish navy. Higher still, in the crags, lay the nests of sea eagles and bearded vultures, while the birds circled apprehensively on the currents above. At the summit, they found the traces of the expedition that Méchain had sent across to light signal flares on the mountain a decade earlier, including stakes marking the line of the meridian. Far below, the glassy Mediterranean was streaked with pale blue bands that wandered to the horizon like rivers upon the sea. To the north they could see Barcelona; to the south Ibiza. Which meant that they could indeed triangulate their way through the Balearic Islands—if the Bureau of Longitudes in Paris approved Méchain’s island-hopping plan.
Méchain had essentially settled on this solution when Delambre’s response finally reached him in mid-March, three months after his query. The Bureau of Longitudes recommended the coastal plan. As Delambre demonstrated mathematically to Méchain, the deviation to the west would not distort the results. This coastal plan, moreover, required only one large sea triangle, whereas the island plan would require at least three. Finally, a baseline could be measured more easily along the mainland shore than on an island. To be sure, admitted Delambre, he was far away, while Méchain was on the spot; hence Méchain alone must decide which plan would ensure the most precise results. He wrote: “I wait with much curiosity, and look forward with much interest, to the good report of your journey in Mallorca.”
Méchain deferred to his colleague’s recommendation. At least the coastal chain was a sure thing, whereas every time he set foot on a boat disaster ensued. This meant, however, that his two months on Mallorca had been a waste of time. He ordered his team to summon their energy for one final foray along the southern coast. Though the prospect was exhausting, he warned his subordinates not to relax their vigilance. Continual self-surveillance is the only protection against error.
Even I, who can claim some experience and competence [in geodesy], who know a bit about what methods to use and when to take precautions, even I work in constant fear. I mistrust myself. I continually solicit the views and intelligence of my colleagues at the Academy and the Bureau of Longitudes, and nothing pains me more than when they respond that they rely entirely on me, and that no one is better placed than I to judge what must be done, to choose the right methods, and to carry them through. At such times I feel as if they are spitting in my face. Nothing comes easily, nothing is simple, when one seeks precision. All it takes to be convinced of this is to do a little observing of one’s own.
In early April 1804 he sailed back across the straits for Valencia, where he hoped to procure passports to scout out stations along the coast. For six weeks, during the finest season for geodetic surveying, Méchain waited for passports in the city of gaudy church spires and pungent yellow dust, an honored guest in the residence of the Barón de la Puebla, while his Spanish friends did bureaucratic battle with the diabolical director, Ximenez Coronado. Méchain was impatient to begin. The sun was stirring vapors from the sea, drawing up miasmas from the coastal plains. The heat accumulated daily. The season of disease was approaching. If Méchain did not measure the coastal stations soon, he would not be able to triangulate across to Ibiza until the following winter.
As soon as his passports arrived in mid-June he set out. In eighteen days he covered some three hundred miles on horseback, accompanied by Enrile’s second in command, zigzagging his way through valleys and over ranges. The royal road to Madrid, then under construction, ran straight across the plains for thirty miles until it hit the mountains; there it turned into a narrow track, impracticable for carriages and hazardous for horses.
Along the coast fishermen pulled their triangular-sailed vessels up onto the sand under the palm trees. On the plains irrigation systems dating back to Moorish rule fed cotton fields, orange groves, and stands of mulberry trees (for silkworms). The mountain slopes to the west were terraced for olive orchards. Lizards swarmed over the rocks, some of them a foot and a half long and fierce enough to intimidate dogs. In all, Méchain located fourteen more stations, including two end points for a baseline that would run alongside the Albufera lagoon, a shallow brackish body of water surrounded by rice fields and teeming with flamingos, herons, and numerous waterfowl. The lagoon, connected to the sea via sluice gates, was notorious for its vapors and pestilent insects. In the morning the wall of the inn would be dark with satiated mosquitoes.
Méchain wrote to his wife that the sun had roasted him alive, scorching his face as black as an African’s, except where his skin was peeling off. The summer heat was only now reaching maximum intensity. During the day the views were obscured by vapors. This meant that they would have to use signal flares and take their triangulations at night. As a precaution, he approached the archbishop of Valencia, a tall Franciscan in tobacco-stained robes, who tended to punch petitioners in the face when they bent to kiss his ring. Would he instruct his priests to warn their parishioners not to harass the strange men with the strange instruments who burned lights at night on the mountaintops? Hostility toward the French was fierce. Despite the presence of Castilian office
rs—or perhaps because of them—Méchain’s party had been threatened on several occasions.
In early July the team dispersed to conduct their nighttime triangulations, beginning at the town of Cullera on the southern edge of the Albufera marsh. While Méchain set up his repeating circle on a rocky outcrop seven hundred feet above the rice fields, each of his collaborators—Captain Enrile, the priest Canellas, loyal Dezauche, and young Augustin—led their respective groups of sailors to the surrounding mountaintop stations and directed their reflectors back at Méchain.
Two weeks later, after Méchain had tacked inland to La Casueleta to set up a new signal by the Roman aqueduct, his collaborators repositioned their reflectors on the surrounding stations. Then, another two weeks later, when he tacked back toward the coast, setting up his repeating circle on a hillock outside the town of Puig, his collaborators again adjusted their reflectors’ positions. By now it was August and the heat was at its most intense. Rather than lodge in the miserable town, a quarter hour walk down the road, Méchain decided to camp out in tents on the hilltop, two hundred feet above the dense coastal air.
Yellow fever had begun to claim new victims. And mixed in with it was something else: what eighteenth-century physicians called “tertian fever” (fièvre tierce). Already it had claimed the life of one of the sailors requisitioned to transport the instruments. On his way to join Méchain at the station outside the town of Puig the sailor had been hospitalized in Valencia, where he died four days later. Several other members of the expedition had been enfeebled by illness. A naval officer, sleeping in the tent beside Méchain on the hillock outside Puig, was seized by a violent fever in the middle of the night. He had to be transported the next morning to a monastery down the coast, then removed to a more salubrious location. Captain Enrile had also fallen ill, though he had since recovered.
More frustrating still, the monk Canellas had inadvertently cost Méchain two weeks of labor. His error of calculation had resulted in a misplaced signal. Those measurements now had to be redone—further proof, if any were needed, that Méchain could not trust others to do his work for him. The monk had also since fallen ill, of a “demi-tertian fever,” and had been bled three times. As a result of these delays Méchain was still outside Puig in late August. He had just turned sixty. In the town at the foot of the hill the disease was subsiding, although three or four deaths were still being reported every day from the town of Puzol a mile up the road. They could hear the funeral bells tolling while they labored. Méchain’s son was still atop La Casueleta; the death toll in the nearby town of Chiva had reached five a day.