types of various sizes from half a kilogram to 1.2 tonnes mounted on steel poles. The result is not unlike a collection of church bells, however they are spread through an open space rather than being confined to a tower, allowing people to walk between them. There are thirty-nine bells in total, spanning 3 octaves. Tuned in the just intonation system, the bells are controlled by computer, and play an ever increasing range of compositions, some commissioned, some submitted by the public. This sound sculpture plays three times a day. The bells were designed by Neil McLachlan and Anton Hassel. In 2010, Spring Innovations were asked to design a new dynamic playing system that was publicly launched on 1 April 2012. Since then the bells have played over 11 million times annually with near complete reliability. They now monitor themselves and report on their playing status daily. Members of the public can down load a player from www.federationbells.com.au and compose and submit their own works online. Circus Oz has incorporated a live event with the Bells for their 2013 season. The ten-metre high, three-legged Angel was installed along the river bank in 2006. The sculpture was commissioned from Melbourne mosaic artist Deborah Halpern for installation in the 'moat' in front of the National Gallery of Victoria in 1985, but off-loaded by the Gallery when major renovations were undertaken in 1999. The William Barak Bridge was officially opened in December 2005 for the 2006 Commonwealth Games. This provides pedestrian access between the middle terrace of Birrarung Marr over the CityLink toll road and railways to the vicinity of the Melbourne Cricket Ground. Horticulture In addition to the mature elms along the river bank and at Speakers Corner, about 200 new trees were planted in the park during its construction. The new plantings focus on Australian species including a mass planting of Macrozamia communis (cycads) on the embankment overlooking Speakers Corner. Also in this area are several Doryanthes excelsa (gymea lilies) and Lepidozamia peroffskyana (pineapple zamia, another cycad). Hundreds of smaller Australian native plants are also present although construction of the William Barak Bridge, which was not part of the original design for the park, destroyed one of the major display plantings on the north-facing embankment of the middle terrace. Additional tree planting for shade and shelter was envisaged for the level areas of the upper and middle terraces, but has not