How did they build Cleopatra's needle?

Answer 1

The obelisk of Hatshepsut, built in the year 1457 BC, during the XVIII dynasty, is the second biggest of all the ancient Egyptian obelisks. Made of one single piece of pink granite, it has a height of 28.58 metres (84ft) and its weight is 343 tonnes (754,600lbs). It is located in the Temple of Amun at Karnak.

Nobody knows for certain how the one block from which the obelisks is made was extracted from the rock. There are two widely accepted theories. The first one maintains that the granite was extracted from the quarry wearing out a block by means of blows given with dolerite balls of a diameter that varied between 12 and 55 cm with an average weight of 6kgs. This wearing out around the block created a passage of sufficient width for one person. Every half metre, approximately, a slave squatted or went on his knees to continue giving blows until the necessary depth was reached. Having arrived at this point, the obelisk was now silhouetted, but the lower side had to be released. For this a tunnel was excavated with the mentioned dolerite balls on both sides of the blocks and its central part was separated with the help of slaves pulling on a series levers.

Another theory, defended above all by the Egyptologists, sustains that in the extraction of blocks sycamore wood wedges were used. The wedges of this wood, which has great absorption capacity, were inserted in the cracks made in granite, which became wet and were exposed to the sun. When they expanded, the granite would crack and break away from the bedrock.

Once the block was extracted, in one way or another, the form was given to the obelisk by means of blows with dolerite balls and polished with sand or crushed rocks.

The transport of the pair of obelisks of Hatshepsut, according to the inscription on its base, lasted 7 months, a relatively short period of time considering how it was done. Once separated in the quarry the monoliths were placed on wooden sledges which were pulled by long lines of slaves hauling on ropes over a prepared causeway to a riverside jetty. An object this size may of taken up to 2,000 slaves to move. To reduce the friction the mud from the Nile was thrown over the tracks. Because of the weight and dimensions of the monolith, it was necessary to use more than one boat for the transport on the river. Several boats were placed in parallel and the obelisk was placed on top of them. Once more, we enter the terrain of the theories, it is also stated that only one ship was used the characteristics of which is unknown, but, of all the existing explanations regarding the transport of the obelisks, this one is the most accepted.

When the monolith arrived at its final destination, the sculpting of the inscriptions was done throughout its four sides, a task for which different stones of different sizes were used, followed by polishing using sand and water as abrasives.

Another key moment was the raising of the obelisk. The presence of grooves in the base of some obelisks has served as the starting point for the elaboration of a theory about this process. Thus, the obelisks were dragged close to their point of erection making them descend through a ramp till they coincided with a groove pointed out in the base of the pedestal. Then, by means of a pulley system and ropes it was hoisted up till it fitted in the base. It is not fully clear the manner in which it slipped on the ramps. One also has to take into account a lot of space was necessary for manoeuvre because of the size of the obelisk. The theory is plausible when it refers to placing the obelisks in big open spaces, but in the specific case of the obelisks of Hatshepsut, these measured 28 metres and the margin for manoeuvre available was between 10 and 12 metres.

Currently only one of the obelisks of Hatshepsut stands high in its original place. Its pair can be seen on the floor of the temple which allows one to appreciate the inscriptions with detail. Other obelisks have met with different destinations. From the time of the Roman Empire the obelisks have been transported to adorn the most emblematic squares in the world. Thus, we can find Egyptian obelisks in Rome, Paris, London, Istanbul and New York. Sometimes stolen, at other times gifted by the Egyptian authorities, of the 27 obelisks which are conserved upright, only 6 are in Egypt: 3 at Karnak, one each in Heliopolis, Luxor and Cairo.