Between 1500 and 1600 BCE, at a time when the Egyptian and Minoan civilizations were thriving, the first major civilization in the Americas, the Olmec culture, was consolidating its power in southeastern Mexico, near today's city of Vera Cruz. By the twelfth century BCE, the Olmecs were producing outstanding art, both stylistic and naturalistic, that was on par with the best being produced in the Old World. The Olmecs are mostly remembered today for the numerous carved stone monumental heads, evidently of their rulers, that now grace museums throughout the world.
The influence the Olmec civilization had on succeeding Mesoamerican cultures was profound. These contributions include writing, a sophisticated calendar, number system (with the earliest known representation of zero), and a ball game similar to soccer that would endure until the Spanish conquest. Human sacrifice may have been another cultural legacy of the Olmecs, but the archaeological evidence is still hazy. Some have speculated that the pantheon of Olmec gods, though under different names and guises, also survived right through the later Mayan and Aztec civilizations.
The Mesoamerican civilizations are especially fascinating because they developed in isolation from the rest of the world. Though many of the cultural contacts between the disparate societies that stretched across Eurasia were indirect, many ideas and technologies were carried back and forth. One can find many cultural similarities between the Han Chinese and Roman Empires, though each mostly knew of the other only through secondhand and thirdhand sources. In the Mesoamerican cultures, there was something unique, and—at least to us—considerably more alien. The Mesoamericans saw blood sacrifice as a necessary element to their religion and worldview. As they saw it, since their gods had used their blood and body parts to create the human race, so must humans return the favor by sacrificing their blood and lives to the gods. For them, offering blood to the gods was as important as water was to irrigation, for if the blood offerings stopped, the world would become a wasteland. Besides sacrificing humans to their gods in great public ceremonies, the individual could also beseech divine assistance by offering his or her own blood. This usually required a great deal of pain—simply opening a vein was evidently for sissies—and involved such grim exercises as passing the barb of a stingray through one's tongue or genitals. Some people have trouble reconciling the advanced scientific achievements of the Mesoamericans with the apparent barbarity of their religions, but to the Olmecs, Mayans, Aztecs, and other societies of the region, such practices were a normal aspect of their lives.
The Olmecs evidently burned lime to make plaster, but they did not use it to the same degree as the cultures that succeeded them. As the Olmecs were declining, grander cultures were arising in the valleys of Mexico and Oaxaca (the Teotihuacán and Monte Albán peoples) and to the southeast, in what are today the nations of Guatemala and Belize and the Mexican state of Yucatán. By the time Commodus was mismanaging the Roman Empire, the Mesoamericans were living in grand and beautiful cities and building pyramids, a few of which would equal those in Egypt. By the first centuries CE, the Mesoamerican cultures were using a tremendous amount of lime for plaster (including types that served as a mural base) and stucco, which they lavishly applied to their public buildings. The Mayans occasionally made concrete, usually in the form of a simple beam, in post and lintel structures, but surviving examples are somewhat crude. Since some of the limestone in Mesoamerica was adulterated with clay—ranging from 10 to 20 percent—the Mayans occasionally produced what is called “natural concrete cement.” Based on a few surviving examples, some of this concrete was among the best in the ancient world, though the Mayans never came close to mastering the material to such bravura effect as had the Romans.
Estimates about how much lime was used varies, but of one thing we can be certain: it was a lot. It appears that the limestone was burned in pits, with the kilning process alone requiring at least thirty-six hours to complete. Since twenty full-grown pine trees were needed as fuel to create just a cubic meter (35.3 cubic feet) of lime, the amount of deforestation caused by the need for farmland and plaster and stucco probably tipped the environmental balance deep in the red.1 Toward the end of the Mayan civilization, during the period called the Late Classic, the Mayans were using lime more sparingly and applying thinner coats of plaster to their walls. Centuries before the Spanish arrived, most of the once-great cities of the Mayans had been lost to the jungle.
The principal Mesoamerican culture encountered by Cortez and the conquistadors in the sixteenth century was the Aztec, whose empire dominated much of southern Mexico. The Aztecs also used lime plasters, but there is no evidence that they ever created concrete. Even though the Aztecs controlled richer agricultural lands than did the Mayans, the fuel requirements for making lime likely restricted the use of plaster to just their principal buildings and temples.
Perhaps one reason why the Mesoamericans never realized the full potential of concrete was related to the difficulty they would have encountered in making forms for the material, for they had never developed metal tools. The carpentry tools used by the Romans were little different from those used in the early nineteenth century: saws, chisels, awls, planes, and so on. Just look at the saw. With a saw, one can not only bring down a tree—though an axe might also be employed—but also make long planks with a very flat surface, similar to the ones employed by the Romans for making concrete walls. The other basic carpentry tools would be needed to create something truly amazing, like the wooden form used for making the Pantheon's dome. However, this still doesn't explain why another concrete application has not been discovered at Mesoamerican sites: artificial stone floors, a common feature of Neolithic temples and dwellings in the Middle East. Perhaps stonemasons were held in high regard for their talent at a craft that took years to master, while concrete was something almost anyone could do. Without the discovery of an inscription that may shed light on the matter, it will remain a subject of speculation.
At the time the Spanish had begun their conquest of the New World, many people back in Europe were excited by the news that a scholar-priest had introduced the definitive edition of an ancient book discovered a few decades earlier in an obscure monastery. Because of its highly technical language, the book had frustrated scholars attempting to decipher certain portions of the text. The book was Vitruvius's On Architecture, and in it were instructions on how to make Roman concrete.
VITRUVIUS REDISCOVERED
It would not be until the fourteenth and fifteenth centuries that the Renaissance began to lift Western civilization from the mire in which it had been stuck for almost a millennium. The Roman Catholic Church, which had for centuries been chained to the counterlogical and antihumanist traditions of the early church fathers, gradually embraced the teachings of St. Thomas Aquinas, a thirteenth-century proponent of Aristotelian logic who believed that the mind of God was both just and rational. It was a crack in the orthodox pavement through which a tree would grow. Scholars began rummaging around old monasteries looking for the surviving texts of pagan authors. The literacy rate slowly grew, though it was still largely restricted to the clergy, some merchants, and a few among the nobility.
In the 1300s, fragments of Vitruvius's book began to appear, and handwritten copies of these began circulating throughout Europe. For almost a century, it was assumed that the complete version of the book would never be found (many ancient works that did survive were nevertheless incomplete, like Tacitus's histories). Then, in 1414, a complete edition of On Architecture was discovered in a Swiss monastery. The discovery naturally caused a sensation, for here was the only complete work on architecture to survive from antiquity, and people were eager to know what great knowledge would be revealed. Initially, it would be little. The text was corrupt in many places—mostly transcription errors—and even the most erudite Latin scholars were often baffled by Vitruvius's technical language and his frequent use of Greek terminology (emplecton? Huh?). Ancient Greek, forgotten in the West for over a thousand years, was being studied once more, but the number of people who were fluent in the ancient tongue was still small, and their reading was mostly restricted to the literary classics, not technical treatises. People would puzzle over Vitruvius's book for decades. Finally, a Franciscan monk with a very unique résumé would come to the rescue.
One of France's better kings was Louis XII. He reigned from 1498 to 1515 and was known to his subjects as the “Father of the People” (Pére du Peuple). He curbed corruption, reformed the legal system, reduced taxes, and kept the meddlesome and occasionally rebellious nobility in check. These actions and policies finally allowed the French to enjoy a stable and efficient government, as well as a period of domestic—though not foreign—tranquility. Louis XII was also a decent general who fought a successful war against the Piedmontese warlord Ludovico Sforza, which won back Milan for France. (After twelve years, the unfortunate city was “lost” again, returning to its traditional role as a treasured football to be kicked back and forth by French kings, Italian princes, and German kaisers.)
Shortly after coming to power, Louis XII invited a remarkable man to his court: Fra Giovanni Giocondo, a Franciscan monk considered one of the lights of the already well-lit Renaissance. Fra Giocondo's title was royal adviser, an appropriately general job description for a man of such wideranging knowledge and interests. Fra Giocondo was one of the great classical scholars of the Renaissance (he had discovered and published Pliny the Younger's correspondence to Emperor Trajan) and was as comfortable with Greek as he was with Latin. If this were not enough, he was also an accomplished and highly regarded architect.2 King Louis wanted his new royal adviser to build a magnificent bridge across the Seine River to the island where Notre Dame Cathedral stood. The monk was certainly up to the task, but for the bridge's construction, Fra Giocondo wanted to try something novel: Roman concrete.
By the time of his bridge commission, the Italian monk had already been studying Vitruvius's book for years, and it is likely that no one then living could so easily grasp the Roman architect's language. Besides being an architect, Fra Giocondo was a pioneering archaeologist who examined ancient ruins with a civil engineer's eye, carefully noting the dozens of different building methods and materials employed by the Romans.
Fra Giocondo wanted to use the waterproof mortar Vitruvius described in his book to build the piers for the new Pont Notre-Dame—the first time in many centuries that Roman concrete would be employed in a construction project. But would it work? Fra Giocondo would be venturing in territory that had been unexplored for a thousand years. Essentially, he was putting his faith in the hands of his ancient predecessor and hoping that the strange formula of lime and pozzolanic soil would perform as described.
It did, and Louis XII was pleased with the magnificent new bridge.3 Upon completion of this project, Fra Giocondo returned to Italy, where he designed and built several structures, including the famed Fondaco dei Tedeschi in Venice, in which Titian and Giorgione would paint some of their most famous murals. In 1511, Fra Giocondo published Vitruvius's On Architecture, a thoroughly annotated and richly illustrated edition that would be the basis of many later translations and that remained the most definitive Latin version for several centuries. Fra Giocondo died a few years later, leaving an architectural and literary legacy that is still treasured today.
Oddly, even though Fra Giocondo had solved the technical mysteries of Vitruvius's book, centuries would pass before concrete was used again. The Italian monk's courage in using the material to build the Pont Notre-Dame would not be emulated by his more conservative contemporaries. Concrete's comeback would have to wait. Its return would be gradual, but unlike before, this time it would refuse to disappear once more in the mists of time and ignorance.