Page:Philosophical Transactions - Volume 145.djvu/139

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At a distance of about five and a half miles N.N.E. of Cairo, and less than four miles, at the time of low water, from the right bank of the Nile, the traveller discovers the solitary Obelisk of Heliopolis, all that remains above ground of that once renowned city of the Pharaohs, the On of Scripture. This obelisk, the oldest known, was erected by Sesurtesen (Sesortosis I. of Manetho) of the Old-Monarchy, and the twelfth Dynasty, about 2300 years before Christ, according to ,and has thus stood at least 4000 years, which, according to the marginal chronology printed in the latest editions of our Bibles, is about 300 years before the death of Noah.

The obelisk is a single block, measuring from the pedestal on which it rests, 67 feet 6 inches, its faces being 6 feet 6 inches at the base, and tapering to 3 feet 10 inches at the lowest line of the pyramidal summit. It is of red granite, such as is found in the district of Assouan, and was doubtless transported from the quarries in that locality.

The walls which surrounded the city are still to be traced by long mounds of earth, covering the unbaked bricks of which they were constructed, in some places from 60 to 65 feet in width, and from 13 to 16 feet in height, enclosing an area of about 1540 by 1100 yards. These mounds are now much more than sufficiently high to keep out the greatest inundation; formerly the water entered by gaps and converted the interior area into a marsh; but in the time of embankments were raised to keep out the inundation water and render the ground cultivable. The land immediately eastward of the obelisk rises abruptly; it is composed of coarse sand and marl, and is out of the reach of the inundation. It appears probable that the site originally chosen for the temple and city of Heliopolis was a portion of the desert line somewhat raised above the level of the rest of the skirt of the desert, and advancing into the low grounds then inundated by the Nile.

On the 8th of June 1851, forty labourers, under the direction of Adjutant of Artillery, were on the ground. The next day was devoted to arrangements, the men being shown where and 1ow the works were to be commenced, and explanations given, that they might have some idea of the nature and object of the operations. A party of young engineers from the Polytechnic School in