Egyptian Obelisks
The obelisk, called TEJEN in the sacred language of the ancient Egyptians, was a term which was synonymous with "protection" or "defense." The needle of stone had the function of perforating the clouds and dispersing negative forces that always threaten to accumulate, in the form of visible storms or invisible ones, and was placed over the temple as a symbol of a petrified ray.
The word "Obelisk" comes from the Greek obeliskos, meaning a prong for roasting. It is a stone that is frequently monolithic, of a quadrangular base, placed upright and ending with a pointed top. It was placed in the center of large open spaces in the temples of the solar god RA. They arose, by the time of the predynastic period cults, to a great sacred stone which was raised in the Temple of Heliopolis, the "City of the Sun."
As with the pyramids, this monument had a primitive relation with the solar cult. As a general rule, obelisks were erected in pairs and served to magically protect the temple.
The obelisk is composed of two parts:the body and the pyramidon. The body is a long block of a conic trunk section and the pyramidon symbolizes the rays of the sun. The top is the point of a pyramid formation which crowns the monolith and rested on a base. It was plated in gold, a metal which the Egyptians affirmed was the "flesh of the gods."
The obelisks originated from the granite quarries of Aswan. In this place an unextracted obelisk still remains within the layer of rock. To 1.200 tons., it would have been the tallest, 41,70 meters, but was abandoned for the workman due to the appearance of fissures in the stone. It may have been the match for the Lateranense obelisk, a possible reason why there is only one in Karnak.
Generally, obelisks have inscriptions on all four sides and also parts of the pyramidon are sometimes carved with bas-relief. These monumente symbolize the stability and the creative force held by the solar god RA. The Egyptians believed that the solar rays brought a great vivifying power even into the grave which would have an effect on the subsequent resurrection of the deceased.
Champollion's notes of his study of the cartdrige of Cleopatra, inscribed on an
obelisk found at Philae by Belzoni, The names of Cleopatra and Ptolemy were the
first words deciphered by Champollion. By analysing the texts of the Rosetta Stone
and comparing them with those on the obelisk of Philae, Champollion had the
brilliant intuition that the names of the pharaohs in cartdrige were in hieroglyphs with
a phonetic value, and that it was therefore possible to establish an equivalence
between hieroglyphic and alphabetic signs.
http://www.egipto.com/obeliscos/histo2.html