We determined that our scale model would be one-fifth of the full size timber kiln, an achievable task. We set about collecting the raw materials for the scale model. Building the scale model kiln required a surprisingly large amount of materials. When we purchased the limestone and wood for the cement kiln a large truck was required to transport our load.
“Okay,” I said to Philippe. “Here is the design sketch; we need to split the timber into appropriate sizes for the kiln. It would be great to use some of your jadeite Maya tools.” However we settled for a steel hatchet and a wedge. The construction of the 4-foot-diameter and 2-foot-high timber kiln went smoothly. Philippe chopped wood into appropriate modules, and I arranged them in the appropriate Maya manner. When the timber array was in place, we stacked the limestone on top around the center of the fire cylinder. We added some pine kindling to the center of the fire cylinder to aid the initial combustion of the thermodynamic system. The scale model that would prove the effectiveness of the Maya blast furnace was now ready for the filming of the demonstration.
The film crew and the host of the documentary assembled, and we went over the script for filming the performance of this Maya invention. When all was ready, the cinema professionals were set to roll the cameras. We had exactly followed the ancient Maya procedures for building the kiln and were proceeding with traditional methods of ignition and burning of the timber blast furnace that would convert the limestone into cement clinkers. We knowingly only violated one of the traditional rules of Maya cements technicians: women were not permitted to be present at a burn, and we had women on board as crew members. We were not going to test modern mores by clearing women from the filming. “Oh, what the hell!” I thought. “This is a scientific experiment. What could go wrong?” It is better to face the anger of the gods than the wrath of an angry female crew member, so I shouted, “Let her rip!”
Philippe had prepared a metal scuttle with hot coals to start the procedure, staying within the Maya “rule book.” A deviation from the standard was the attachment of a pyrometer to the interior of the fire cylinder to monitor the levels of burn temperatures. “Action!” shouted the director. Cameras rolled and the test initiated, with the host pouring hot coals into the fire cylinder.
There was an immediate ignition of the pine kindling, as the rosin-filled slivers of wood pyrolyzed. Gases from the kindling streamed up and ignited. The flame in the center of the cylinder began to shoot upward in a column. We observed the meter on the pyrometer as the needle crawled to the right of the scale indicating higher and higher temperatures. The camera kept rolling. The center of the fire cylinder was now in full combustion. The thermodynamic action of the kiln was driving the red flames higher and higher. The needle on the pyrometer crawled to the right as it registered higher temperatures. The fire grew hotter, and the flames turned to orange as the wood began to release gases that increased the rate of combustion, lowered the interior pressure, and sucked oxygen-rich air from the exterior into the bottom of the cylinder. The flames roared upward to a height of 2 meters (Figure 6-5). The host of the History Channel film maintained a running narrative of the testing activities, describing the color and height of the flame and the temperature reading. The flame turned a light red as the system began to burn hotter. There was no smoke from the burn, due to the highly efficient thermodynamic reactions developed by the Maya kiln. The upper scale of the pyrometer was calibrated in Fahrenheit and the lower scale indicated the Celsius scale. The needle moving to the right indicated higher temperatures. The crew urged the needle to higher temperatures: 200 degrees Celsius, 400 degrees, 600 degrees.…The increase was slowing, but still moved upward.
Figure 6-5: Flames soar as a scale model Maya cement kiln operates. Author’s image.
There had to be a limit to our test. The high temperature of the fire was quickly consuming the dry oak timber. The temperature rose to 800 degrees and stalled at that temperature level. The combustion stabilized as the wood fuel became expended and the temperature began to drop. We had not soaked the wood fuel in water. (Our test actually combined show biz with scientific principles. The director wanted a dynamic blaze, and we did not know how much the soaked wood would affect the burn.) The reduced size of the timber-powered reactor and dry fuel supply resulted in a short burn and reduced temperature. As the brave little Maya blast furnace began to reduce its temperature, the director called out, “Cut!” The crew filmed some B-rolls, then slowly began to gather their gear and pack it up. There were hearty goodbyes as they sped into the night.
After their departure we assessed the performance of the scale model. First, the filming was a success, even with dry wood. Second, Maya technology attained another proof of its capabilities. The scale model was able to validate the thermodynamic performance and capabilities of the Maya timber kiln. The scale model performed as described by the ancient Maya cement fabricators. The flames shot skyward in a vertical column. The temperature of the scale model kiln was elevated to 800 degrees. This is twice the burning temperature of wood. My calculations of this heat level and the model’s similitude indicated a potential temperature production of well over the 1,400 degrees required to transform limestone into cement.
I guess the Maya fabricators were wrong about allowing women to be present at a kiln burn.
7
Towers in the Forest
The 1842 landmark publication Incidents of Travel in Central America, Chiapas, and Yucatán became an immediate best-seller. John Lloyd Stephens’s chatty prose and the crisp illustrations of Frederick Catherwood spurred the imaginations of its readers on flights of fancy to the lost civilization set in a tropical paradise. This masterpiece of prose that introduced the Maya to the world is considered to be a more learned and illuminating work than many dissertations on the Maya published by later scholars. Stephens offered the world its first glimpse of the intellectual, artistic, and engineering masterworks of the Maya culture. The pair was the first foreigners to observe and describe the strange architecture, rich ornamentation, and soaring structures that were the legacy bequeathed by the collective genius of the Maya civilization.
Until the end of the 19th century, scholars and archaeologists held forth multiple theories relative to the origin of the Maya. Opinions relative to their origin were strongly Eurocentric, and scholars offered theories that claimed the origins of the Maya to be Greek, Roman, Chaldean, Phoenician, or even Egyptian. Scholars also perceived that the ruined cities were thousands of years old. Stephens, with his level-headed thinking, and his knowledge of classic civilizations and languages, made logical postulations about the origin of the Maya: 1) the cities were hundreds of years old, not thousands, 2) the builders were not travelers from afar but were the ancestors of modern Maya living in the Yucatán at the start of the Spanish conquest, and 3) the hieroglyphics seen carved on stone throughout the region indicated the same culture and belief values throughout the Maya area. John Lloyd Stephens was “spot on” when he correctly theorized the age, cultural consistency and the origin of the Maya civilization. Yes, the Maya civilization was homegrown, all natural, purely domestic, indigenous, and born in the Yucatán.
Catherwood’s illustrations and vivid descriptions of the ancient skyscraping towers and exotic palaces looming above the emerald forest were proof that the cities had resisted the test of time, the attack of the tangled jungle environment, the tropical heat and rain, and countless hurricanes and devastating earthquakes. The resilient structures were mute testimony to the skilled technology of the Maya. The buildings in the sprawling cities had resisted degradation because the large structures had been constructed of durable building materials and formed in unique structural geometries. These unique structures were constructed with cast-in-place concrete structures that were erected more than 1,800 years prior to similar western technology. If Maya technology had not achieved elevated standards that were capable of constructing high-strength structures, but instead had constructed their cities of timber, brick, and thatch,
Stephens would have encountered completely ruined and degraded cities that would have been buried deep below the jungle surface. No obvious evidence of these Maya cities would have been found.
The Maya applied innovative methods of agriculture technology including agronomy, terraces, raised fields, and efficient irrigation systems. This enhancement of agriculture products and yield was achieved, against all odds, in a fickle environment with poor soil, tropical heat, and a seasonal desert due to cycles of a rainy season followed by a dry season. The development of Maya civilization and its sciences, technology, and sophisticated city-states can be traced directly to the food surplus produced by efficient Maya agriculture. The abundant food surplus enabled sedentary lifestyles and encouraged the Maya to build villages and towns that support full-time artisans and technicians. These specialists were not required to grow their own food and so had adequate time to develop special industrial skills. The Pre-Classic sky-watchers, artisans, and technicians evolved into the astronomers, mathematicians, scribes, physicians, and engineers that expanded into the collective intellectual genius of the Maya civilization. Maya agriculture had set them free.
The variety of industrial skills and numbers of technicians and artisans expanded. The burgeoning of this multi-tasking society and its need to operate as an efficient urban entity elevated the role and organization of the political elite and the management bureaucracy that was required to govern the population centers. The population centers became more defined, villages grew into towns, and towns into cities. As the cities grew in parallel with the scientific and technical character of the culture, the basic Pre-Classic building consisted of a timber skeleton frame lashed together and covered with a thatched roof and wattle walls (Figure 7-1). This basic structure then evolved into more permanent and sophisticated structures that were able to resist the harsh environment, earthquakes, and wind storms while minimizing maintenance requirements. Specialized technologies were required to construct larger and taller buildings, and to create an infrastructure that satisfied the demands for water resources and transportation needs of the urban population. Maya engineers enhanced their capabilities in hydraulics and water management to collect, store, and distribute large volumes of potable water that enabled a safe and comfortable life style in Maya urban centers. As the power elite, scientific, technical, and merchant classes grew, they set up shop in the city center to be close to economic activities and the market place for trading operations. The growing wealth of the urban centers enhanced the need for specialized building systems. Buildings grew in size and configuration, and became more elaborate.
Figure 7-1: A typical Maya house that has been in use for thousands of years. Author’s image.
Their invention of a self-sufficient city, with supporting agriculture in the hinterlands, was not a new idea in historical terms. However, unlike cities in other civilizations, Maya cities became more independent, becoming incubators of trade, sciences, technologies, learning, and specialized trades. City-states, bound together by the mutual goals of trade, a common culture, and scientific concepts, developed into a political network, a logical evolution. The cities grew stronger and created an integrated network of commerce.
The Growth and Development of City-States
City building had expanded throughout the Maya zone by the late Pre-Classic Period. The Maya gravitated toward a political model of power and economic wealth based on a city-state concept. During the Classic Period, more than 50 independent Maya power centers evolved into a network of autonomous city-states. This political phenomenon of independent city-states morphed into a successful intra-city trade and political network. The city-state network became the locus of political, intellectual, and economic power throughout the Maya world.
Why city-states? We can attribute this to the individuality of the Maya to choose independence over being controlled by outside influences. The civilization would not have had its longevity and character if it had chosen another course of political organization. The route of the empire as a political organization, as was chosen by the majority of other great civilizations, including the Roman, Egyptian, and Aztec civilizations, forced a widespread territory to operate under a lone power center. The empire had requirements for a large-standing army to control its wide-ranging territory and systems to collect the tribute paid by the conquered people. Empires tended to be single dimensional in many aspects, and the cost of large-standing armies to maintain control reduced the economic power that could be applied to science and technology.
The city-state political system enhanced the urban fabric of each city, as well as the intellectual capability of individual Maya cities. Maya city-states enjoyed an advantage over the economics and politics of an empire. They were self-reliant centers of administrative, commercial, scientific, and technical activities that capitalized on the diversity of industry and market opportunities contributed by other city-states within the trade network. They were spared the expense of a large, wide-ranging, standing army. The alliances of the city-states were generated from the lucrative trade and cultural exchange, rather than from external conquest. There were, of course, exceptions. Larger city-states drawing on their great wealth and greater political power commanded smaller cities within their sphere. Larger and more powerful city-states were able to conquer other weaker city-states and create regional city-states.
The further advantage of the network alliances of city-states lay in their synergistic enhancement as incubators of scientific and technical concepts. A certain city-state would collect ideas from the other city-states, then enhance the concept in their own in-house “think tank.” The borrowed concept would be assessed, then nourished, improved, and disseminated other city-states via the interchange of commercial trade activities. Multi-city political systems relied on this reciprocal system of trade, and the diffusion and dissemination of technological concepts. By contrast, an empire with a single central city would likely have a single center of learning and could not be adaptive to outside ideas.
The various divisions of labor and industrial disciplines required specialized, functional buildings with vertical and horizontal functional spaces designed to satisfy the operations of each industry or activity. There was also a need for urban traffic circulation, open space plazas, and an efficient infrastructure. Specialized structures were constructed for specific functions and tailored to the needs of the city. City planners and engineers met the challenge of the burgeoning population with a never-ending construction program and an enhanced water-management system. (In the late Classic Period, Maya cities boasted populations of 100,000 people. At the same time, the city of Rome had a population of 35,000 and the city of Paris was home to 20,000 inhabitants.) The infrastructure included the construction of an ample water management system with water collection, storage, and delivery systems that enabled the survival of the densely populated cities during the seasonal drought. This infrastructure became an integral part of the design of the cityscape. Plazas, hardscapes, roadways, and buildings all became part of the water collection system. The roofs of structures, roads, and plazas were designed and constructed to slope toward water-collection channels.
A typical classic Maya polity was a self-reliant city-state governed by a lord who served as the ruler. The domain of the city-state consisted of a capital city with a finite territory comprised of smaller towns and villages surrounded by the farmland that supported the population with its agricultural needs. In most cases, the capitals of city-states were not at great distances from each other. The cities seldom required more than two to three days travel between them. The closeness of the cities enhanced technology, trade, and, most importantly, the exchange of ideas. Each of the various city-states possessed valuable natural resources that were special to that city and provided a wide variety of industrial products that formed the basis of their viable trade network. The commercial network that developed between the larger and smaller city-states was based on the trade exchange and the need for specific
products that were unique to a certain city-state.
The flow of commercial goods and materials between the city-states and the lively traffic activities between them resulted in the need for the construction of a network of all-weather, paved highway system connecting the city-states. The network of Maya roads featured long-span bridges, rest stations, and drainage structures.
The growth of specialized disciplines in each city resulted in the development of nodes or precincts in the cityscape devoted to specific disciplines or industrial functions. These specialized disciplines required different types of structures to serve their needs. City planners met this need by establishing sectors or neighborhoods within a city for these disciplines. Urban planning and technology were required to construct the functional structures for the cities and develop corresponding infrastructure. The resulting functional forms of buildings had requirements in the size of plan, interior space, and height of floor levels, interior light, and geometry. Applying multi-discipline technologies, Maya engineers created functional buildings using their durable construction materials. These materials included cast-in-place concrete, high-strength timber, and composite stone and concrete structures that were formed in a variety of innovative geometric shapes.
The grand plazas in the cities were the center of the activities and functions that gave energy to the city. These large greenswards and hardscapes of the urban centers were surrounded by large-scale monumental buildings. The buildings housed administrative, economic, religious, educational, and scientific functions. The plazas were replete with large stone stele covered with carved hieroglyphics and figures of personages that described the historic sagas of the city. During a typical day in the life of a Maya city, the populace would stream into the plaza, carrying out their business, shopping, trading, and sharing gossip while traversing the wide open space that became the crossroads, as well as a place of assembly, for the denizens of the city. The plazas served as the venue for large assemblies of the faithful for public manifestations of pageantry, ritual, ceremonial rites, and celebration that were carried out and performed on outdoor platforms and the temples encircling the plaza. The tropical climate made the construction of large, enclosed structures impractical for the gathering of crowds. Moreover, though only hundreds could gather in overheated interior spaces, thousands could assemble in the cool evening air of the plaza. This led the Maya engineers to design interior spaces for more traditional applications, in a size and volume similar to their traditional houses or ná. Long-span structures were reserved for monumental statements such as entry arches to cities.
The Lost Secrets of Maya Technology Page 14