His necropolis also included the Sphinx, a mysterious limestone monument with the body of a lion and a pharaoh's head. The Sphinx may stand sentinel for the pharaoh's entire tomb complex. The third of the Giza Pyramids is considerably smaller than the first two.
Built by Pharaoh Menkaure circa B. Each massive pyramid is but one part of a larger complex, including a palace, temples, solar boat pits, and other features. The ancient engineering feats at Giza were so impressive that even today scientists can't be sure how the pyramids were built. Yet they have learned much about the people who built them and the political power necessary to make it happen.
The builders were skilled, well-fed Egyptian workers who lived in a nearby temporary city. Archaeological digs on the fascinating site have revealed a highly organized community, rich with resources, that must have been backed by strong central authority.
It's likely that communities across Egypt contributed workers, as well as food and other essentials, for what became in some ways a national project to display the wealth and control of the ancient pharaohs. Such revelations have led Zahi Hawass , secretary general of Egypt's Supreme Council of Antiquities and a National Geographic explorer-in-residence, to note that in one sense it was the Pyramids that built Egypt—rather than the other way around.
If the Pyramids helped to build ancient Egypt, they also preserved it. Giza allows us to explore a long-vanished world. Tomb art includes depictions of ancient farmers working their fields and tending livestock, fishing and fowling, carpentry, costumes, religious rituals, and burial practices. Inscriptions and texts also allow research into Egyptian grammar and language.
To help make these precious resources accessible to all, Der Manuelian heads the Giza Archives Project, an enormous collection of Giza photographs, plans, drawings, manuscripts, object records, and expedition diaries that enables virtual visits to the plateau.
It actually requires 5, or fewer men, including the stone-setters. Now, the stone-setting gets a bit complicated because of the casing, and you have one team working from each corner and another team working in the middle of each face for the casing and then the core. And I'm going to gloss over that. But the challenge is out there: 5, men to actually do the building and the quarrying and the schlepping from the local quarry.
This doesn't count the men cutting the granite and shipping it from Aswan or the men over in Tura [ancient Egypt's principal limestone quarry, east of Giza]. That increases the numbers somewhat, and that's what things like NOVA's series on ancient technologies really bring home, I think.
No, we're not recreating ancient society and ancient Pyramid-building percent, probably not even 60 percent. But we are showing some nuts and bolts that are very useful and insightful, far more than all the armchair theorizing.
One of the senior vice presidents decided to take on for a formal address for fellow engineers a program management study of the Great Pyramid. So these are not guys lifting boilers in Manhattan; these are senior civil engineers with one of the largest construction corporations in the United States. I'm sure they'd be happy to go on record with their study, which looked at what they call "critical path analysis.
What tools did they have? They contacted me and other Egyptologists, and we gave them some references. Here's what we know about their tools, the inclined plane, the lever, and so on. And without any secret sophistication or hidden technology, just basically what archeologists say, this is what these folks had.
They have very specific calculations on every single aspect, from the gravel for the ramps to baking the bread. I throw that out there, not because that's gospel truth, but because reasoned construction engineers, who plan great projects like bridges and buildings and earthworks today, look at the Great Pyramid and don't opt out for lost civilizations, extraterrestrials, or hidden technologies.
No, they say it's a very impressive job, extraordinary for the people who lived then and there, but it could be done. They are human monuments. One of the most compelling pieces of evidence we have is graffiti on ancient stone monuments in places that they didn't mean to be shown. Like on foundations when we dig down below the floor level, up in the relieving chambers above the King's chamber in the Great Pyramid, and in many monuments of the Old Kingdom—temples, other pyramids.
Well, the graffiti gives us a picture of organization where a gang of workmen was organized into two crews, and the crews were subdivided into five phyles. Phyles is the Greek word for tribe. Receive emails about upcoming NOVA programs and related content, as well as featured reporting about current events through a science lens. The phyles are subdivided into divisions, and the divisions are identified by single hieroglyphs with names that mean things like endurance, perfection, strong.
Okay, so how do we know this? You come to a block of stone in the relieving chambers above the King's chamber. First of all, you see this cartouche of a King and then some scrawls all in red paint after it. That's the gang name. And in the Old Kingdom in the time of the Pyramids of Giza, the gangs were named after kings.
So, for example, we have a name, compounded with the name of Menkaure, and it seems to translate "the Drunks or the Drunkards of Menkaure. In fact, it gets more intriguing, because in certain monuments you find the name of one gang on one side of the monument and another gang, we assume competing, on the other side of the monument. You find that to some extent in the Pyramid temple of Menkaure. It's as though these gangs are competing.
So from this evidence we deduce that there was a labor force that was assigned to respective crew, gang, phyles, and divisions. There's some evidence to suggest that people were rotated in and out of the raw labor force. So you could be a young man in a village, say, in Middle Egypt, and you had never seen more than a few hundred people in your village, maybe at market day or something. And the King's men come, and it may not have been entirely coercion, but it seems that everybody owed a labor tax.
We don't know if it was entirely coercive, or if, in fact, part of it was a natural community donation as in the Incan Empire, for example, to building projects where they had a great party and so on.
But, anyway, they started keeping track of people and their time on the royal labor project. And if you were brought from a distance, you were brought by boat. Can you imagine floating down the Nile and—say you're working on Khafre's Pyramid—and you float past the Great Pyramid of Meidum and the Pyramids of Dashur, and, my God, you've never seen anything like this.
These are the hugest things. We're talking about a society where they didn't have cameras, you didn't see yourself age. You didn't see great images. And so here are these stupendous, gigantic things thrust up to the sky, their polished white limestone blazing in the sunshine. And then they go on down to Giza, and they come around this corner, actually the corner of the Wall of the Crow, right into the harbor, and there's the Khufu Pyramid, the biggest thing on the planet actually in the way of a building until the turn of the 20th century.
And you see, for the first time in your life, not a few hundred, but thousands, probably, of workers and people as well as industries of all kinds.
You're rotated into this experience, and you serve in your respective crew, gang, phyles, and divisions, and then you're rotated out, and you go back because you have your own large household to whom you are assigned on a kind of an estate-organized society. You have your own village, maybe you even have your own land that you're responsible for. So you're rotated back, but you're not the same.
You have seen the central principle of the first nation-state in our planet's history—the Pyramids, the centralization, this organization.
They must have been powerful socializing forces. Anyway, we think that that was the experience of the raw recruits. Even before these revelations, I was deeply fascinated by the HX, the last of the great rotor machines. This particular unit, different from the one I had seen a decade before, had been untouched since I immediately began to plan the restoration of this historically resonant machine. People have been using codes and ciphers to protect sensitive information for a couple of thousand years.
The first ciphers were based on hand calculations and tables. In , a mechanical device that became known as the Alberti cipher wheel was introduced. Then, just after World War I, an enormous breakthrough occurred, one of the greatest in cryptographic history : Edward Hebern in the United States, Hugo Koch in the Netherlands, and Arthur Scherbius in Germany, within months of one another, patented electromechanical machines that used rotors to encipher messages.
Thus began the era of the rotor machine. Scherbius's machine became the basis for the famous Enigma used by the German military from the s until the end of WW II. To understand how a rotor machine works, first recall the basic goal of cryptography: substituting each of the letters in a message, called plaintext, with other letters in order to produce an unreadable message, called ciphertext. It's not enough to make the same substitution every time—replacing every F with a Q , for example, and every K with an H.
Such a monoalphabetic cipher would be easily solved. A simple cipher machine, such as the Enigma machine used by the German Army during World War II, has three rotors, each with 26 positions. Each position corresponds to a letter of the alphabet. Electric current enters at a position on one side of the first rotor, corresponding to a letter, say T. The current travels through two other rotors in the same way and then, finally, exits the third rotor at a position that corresponds to a different letter, say R.
So in this case, the letter T has been encrypted as R. The next time the operator strikes a key, one or more of the rotors move with respect to one another, so the next letter is encrypted with an entirely different set of permutations.
In the Enigma cipher machines [below] a plugboard added a fixed scramble to the encipherment of the rotors, swapping up to 13 letter pairs.
A rotor machine gets around that problem using—you guessed it—rotors. Start with a round disk that's roughly the diameter of a hockey puck, but thinner. On both sides of the disk, spaced evenly around the edge, are 26 metal contacts, each corresponding to a letter of the English alphabet.
Inside the disk are wires connecting a contact on one side of the disk to a different one on the other side. The disk is connected electrically to a typewriter-like keyboard. When a user hits a key on the keyboard, say W , electric current flows to the W position on one side of the rotor. The current goes through a wire in the rotor and comes out at another position, say L. However, after that keystroke, the rotor rotates one or more positions.
So the next time the user hits the W key, the letter will be encrypted not as L but rather as some other letter. Though more challenging than simple substitution, such a basic, one-rotor machine would be child's play for a trained cryptanalyst to solve. So rotor machines used multiple rotors. Versions of the Enigma, for example, had either three rotors or four. In operation, each rotor moved at varying intervals with respect to the others: A keystroke could move one rotor or two, or all of them.
Operators further complicated the encryption scheme by choosing from an assortment of rotors, each wired differently, to insert in their machine. Military Enigma machines also had a plugboard, which swapped specific pairs of letters both at the keyboard input and at the output lamps.
The rotor-machine era finally ended around , with the advent of electronic and software encryption, although a Soviet rotor machine called Fialka was deployed well into the s.
The HX pushed the envelope of cryptography. For starters it has a bank of nine removable rotors. The unit I acquired has a cast-aluminum base, a power supply, a motor drive, a mechanical keyboard, and a paper-tape printer designed to display both the input text and either the enciphered or deciphered text.
In encryption mode, the operator types in the plaintext, and the encrypted message is printed out on the paper tape. Each plaintext letter typed into the keyboard is scrambled according to the many permutations of the rotor bank and modificator to yield the ciphertext letter. In decryption mode, the process is reversed.
The user types in the encrypted message, and both the original and decrypted message are printed, character by character and side by side, on the paper tape. While encrypting or decrypting a message, the HX prints both the original and the encrypted message on paper tape.
The blue wheels are made of an absorbent foam that soaks up ink and applies it to the embossed print wheels. Beneath the nine rotors on the HX are nine keys that unlock each rotor to set the initial rotor position before starting a message.
That initial position is an important component of the cryptographic key. To begin encrypting a message, you select nine rotors out of 12 and set up the rotor pins that determine the stepping motion of the rotors relative to one another.
Then you place the rotors in the machine in a specific order from right to left, and set each rotor in a specific starting position. Finally, you set each of the 41 modificator switches to a previously determined position. To decrypt the message, those same rotors and settings, along with those of the modificator, must be re-created in the receiver's identical machine. All of these positions, wirings, and settings of the rotors and of the modificator are collectively known as the key.
The HX includes, in addition to the hand crank, a nickel-cadmium battery to run the rotor circuit and printer if no mains power is available. A volt DC linear power supply runs the motor and printer and charges the battery.
The precision volt motor runs continuously, driving the rotors and the printer shaft through a reduction gear and a clutch. Pressing a key on the keyboard releases a mechanical stop, so the gear drive propels the machine through a single cycle, turning the shaft, which advances the rotors and prints a character.
The printer has two embossed alphabet wheels, which rotate on each keystroke and are stopped at the desired letter by four solenoids and ratchet mechanisms. Fed by output from the rotor bank and keyboard, mechanical shaft encoders sense the position of the alphabet printing wheels and stop the rotation at the required letter.
Each alphabet wheel has its own encoder. One set prints the input on the left half of the paper tape; the other prints the output on the right side of the tape. After an alphabet wheel is stopped, a cam releases a print hammer, which strikes the paper tape against the embossed letter. At the last step the motor advances the paper tape, completing the cycle, and the machine is ready for the next letter. Animal bones found at the village show that the workers were getting the best cuts of meat.
More than anything, there were bread jars, hundreds and thousands of them — enough to feed all the workers, who slept in long, purpose-built dormitories.
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