The Sydney Opera House is such an iconic landmark that it would be virtually impossible to write anything original so I have gathered together the pictures I took of it from various perspectives and times of the day. The architect of Sydney Opera House, Jørn Utzon was a relatively unknown 38 year old Dane until January 29, 1957 when his entry, scheme number 218, was announced winner of the ‘International competition for a national opera house at Bennelong Point, Sydney’. With his vision the City of Sydney was to become an international city. The completion of this building created a piece of architectural art that became iconic, a symbol of the times, like the Pyramids, the Parthenon of Athens, the Colesseum/Aqueducts of Rome, the soaring Gothic cathedrals of medieval Europe and in more modern times the Eiffel Tower, the skyscrapers and the San Francisco Golden Gate Bridge made possible by cheap steel from Henry Bessemer in Europe and Andrew Carnigie in America. No matter the perspective or time of day, the Sydney Opera House gives you that little chill that tells you that you are in the presence of greatness.
One of the things our early ancestors wanted to do was to build structures for housing, walls for protection and special buildings for religion. Building a wall from rough stone is time consuming but possible as we have seen in the last post. If you have a lot of large flat stones and you are building rather low buildings, you don't need to make an arch, you can just put a flat stone on top of stone pillars and you have an opening. The problem with stone pillars topped with a flat lintel is that it cannot bear much weight. As seen in the figure to the right, when a large force is applied downward, the lintel beam is alternately compressed on the upper side and pulled outwards on the bottom. Rock is very incompressible but often has small imperfections that allow cracking on the bottom, leading to failure. This same principle is the reason we can scratch glass and break it along the resulting fault. If you are using brick, the problem becomes insurmountable, you must have an arch or a stone lintel to make an opening in the wall (a door or window). Everyone has seen the karate trick of breaking a brick held by two blocks of wood. The only problem with arched openings is that the arch converts downward force into sideways forces and must be buttressed on both sides.
Dolní Věstonice is an open-air site located along a stream, in the south Czech Republic on the northern slopes of the Pavlovske Hills, close to the village of Pavlov. Its people hunted mammoths and other herd animals, saving mammoth and other bones that could be used to construct a fence-like boundary, separating the living space into a distinct inside and outside. In this way, the perimeter of the site would be easily distinguishable. At the center of the enclosure was a large bonfire and huts were grouped together within the barrier of the of the mammoth bones. The radiocarbon dates for the occupations at DVII are 27,070-25,570 years uncal BP, which calibrates to 31,500 years ago according to the INTCAL calibration curve (Reimer et al. 2009). The mammoth deposit (202 bones) is generally thought to be contemporary with one or more of these occupations and has been dated to 26100 uncal BP (Svoboda, 1991).