One of the design problems that confronted Wren was to create a landmark dome, tall enough to visually replace the lost tower of St Paul’s, while at the same time appearing visually satisfying when viewed from inside the building. Wren planned a double-shelled dome, as at St Peter’s Basilica. His solution to the visual problem was to separate the heights of the inner and outer dome to a much greater extent than had been done by Michelangelo at St Peter’s, drafting both as catenary curves, rather than as hemispheres. Between the inner and outer domes, Wren inserted a brick cone which supports both the timbers of the outer, lead covered dome and the weight of the ornate stone lantern that rises above it. Both the cone and the inner dome are 18 inches thick and are supported by wrought iron chains at intervals in the brick cone and around the cornice of the peristyle of the inner dome to prevent spreading and cracking.
…with not much to do with Cleopatra in spite of the nickname.
Cleopatra’s Needle in London is one of three similar named Egyptian obelisks and is located in the City of Westminster, on the Victoria Embankment near the Golden Jubilee Bridges. It is close to the Embankment underground station. It was presented to the United Kingdom in 1819 by the ruler of Egypt and Sudan Muhammad Ali, in commemoration of the victories of Lord Nelson at the Battle of the Nile and Sir Ralph Abercromby at the Battle of Alexandria in 1801. Although the British government welcomed the gesture, it declined to fund the expense of transporting it to London.
Made of red granite, the obelisk stands about 21 metres (69 ft) high, weighs about 224 tons and is inscribed with Egyptian hieroglyphs. It was originally erected in the Egyptian city ofHeliopolis on the orders of Thutmose III, around 1450 BC. The material of which it was cut is granite, brought from the quarries of Aswan, near the first cataract of the Nile. The inscriptions were added about 200 years later by Ramesses II to commemorate his military victories. The obelisks were moved to Alexandria and set up in the Caesareum – a temple built by Cleopatra in honor of Mark Antony or Julius Caesar – by the Romans in 12 BC, during the reign of Augustus, but were toppled some time later. This had the fortuitous effect of burying their faces and so preserving most of the hieroglyphs from the effects of weathering.
see the full walk:https://dorsetwalkerblog.wordpress.com/st-pauls-to-hampton-via-putney/