How is an obelisk constructed?

Answer 1

The word "obelisk" comes from the Greek word obelos, meaning a roasting spit or nail. Obelisks are typical examples of ancient Egyptian art; they have an elegant slender form, a square base, and end in a pyramid-shaped point. As a rule, the height of an obelisk was ten times the diagonal measurement of the base.

Its shape is thought to represent the descending rays of the sun. An obelisk usually stood in front of a pylon the ceremonial entrance to a temple. Ancient obelisks were often made from a single piece of stone, whereas most modern obelisks are made of several stones.

Obelisks were usually carved out of reddish-coloured granite found at Aswan. Sometimes dark grey basalt was used.

The dimensions varied: the tallest known obelisk remains unfinished in a cave at Aswan (about 40m) and the smallest is less than 2 metres in height. On many obelisks there are inscriptions in hieroglyphics saying to which gods they were dedicated and to the Pharaoh who ordered their erection.

The huge unfinished obelisk at a cave at Aswan helps to show us how such monuments were made. First of all the Egyptians insisted that the stone to be used should have no defects, cracks or blemishes. Next the rock was cleaned and the surface of the rock was scraped until it was smooth and flat. After smoothing, the contours of the obelisk were marked out on the ground and a deep ditch was bashed out of the rock out around them by gangs of slaves hammering away with pounding balls made from dolerite. These were especially hard stones made from dolerite, dark coloured basalt from the desert valleys of Egypt. These stones weighed anything up to 5 kilograms each.

The fourth face of the obelisk was torn from the seam of rock with enormous wooden wedges which were driven into previously prepared holes at regular intervals. The wedges were soaked with water, and as they expanded the rock split.

At this stage hundreds maybe thousands of slaves, depending on the size of the obelisk, worked with ropes and jacks to raise the obelisk from the ditch and to heave it on to planks resting upon a massive sledge. It was a scene of organised chaos as hordes of slaves, swarmed about the great stone. Although there was no throbbing machinery there was noise: of stone grinding on stone, the creaking of straining timber, the shouts of the foremen, the chanting of slaves.

Once it rested safely on its sledge, the obelisk was dragged to the bank of the Nile. Here it was received by more gangs of slaves who then loaded it onto a long barge to be taken to its destination.

On arrival, the obelisk had to be hauled on its sledge from the river to its final resting place. Again hundreds or even thousands of labourers, depending on its size were pressed into service.

The next task was to pull the obelisk upright. As some monuments weighed up to 500 tonnes, this was obviously quite a problem and nobody today knows exactly how it was done. One possible method was that the base of the obelisk was placed on the edge of the pedestal on which it was going to stand. The obelisk was made so that one side of the base could be fitted into a slot cut in the pedestal. This prevented the obelisk from slipping while it was actually going up.

While the obelisk was raised by ropes and jacks, a heap of material (usually bricks) was pushed underneath it to support it and keep it steady.

Finally the heap of bricks grew high enough to allow the obelisk to stand upright on its pedestal. Then the slaves were set to work removing the material.