Automatic Door
An automatic door, also known as an auto door, is a door that opens automatically, usually on sensing the approach of a person.
In the 1st century AD, mathematician Heron of Alexandria in Roman Egypt invented the first known automatic door. He described two different automatic door applications. The first application used heat from a fire lit by the city's temple priest. After a few hours atmospheric pressure built up in a brass vessel causing it to pump water into adjacent containers. These containers acted as weights that – through a series of ropes and pulleys – would open the temple's doors at about the time people were to arrive for prayer. Heron used a similar application to open the gates to the city.[1]
In 1931, engineers Horace H. Raymond and Sheldon S. Roby of the tool and hardware manufacturer Stanley Works designed the first model of an optical device triggering the opening of an automatic door. The invention was patented and installed in Wilcox's Pier Restaurant in West Haven, Connecticut for the benefit of waiters carrying plates of food and drink. The entire system plus installation was sold for $100.[2][3]
In 1954, Dee Horton and Lew Hewitt invented the first sliding automatic door. The automatic door used a mat actuator. In 1960, they co-founded Horton Automatics Inc and placed the first commercial automatic sliding door on the market.[4]
Wiltshire (/ˈwɪlt.ʃər, -ʃɪər/;[1] abbreviated to Wilts) is a ceremonial county in South West England. It borders Gloucestershire to the north, Oxfordshire and Berkshire to the east, Hampshire to the south-east, Dorset to the south, and Somerset to the west. The largest settlement is Swindon, and Trowbridge is the county town.
The county has an area of 1,346 sq mi (3,490 km2) and a population of 720,060. The county is mostly rural, with the centre and south-west sparsely populated. After Swindon (183,638), the largest settlements are the city of Salisbury (41,820) and the towns of Chippenham (37,548) and Trowbridge (37,169). For local government purposes the county comprises two unitary authority areas: Swindon and Wiltshire.
Undulating chalk downlands characterize much of the county; the North Wessex Downs in the east, Salisbury Plain in the centre and Cranbourne Chase in the south. The north-west is part of the Cotswolds, a limestone area. The county's major rivers are both called the Avon: the northern Avon enters the county in the north-west and flows in a southwesterly direction before leaving it near Bradford-on-Avon; the southern Avon rises on Salisbury Plain, flows through Salisbury and then into Hampshire.
Salisbury Plain is noted for the Stonehenge and Avebury stone circles, which together are a UNESCO World Heritage Site, and other ancient landmarks. Much of the plain is a training area for the British Army. The city of Salisbury is notable for its medieval cathedral. Large country houses open to the public include Longleat, where there is also a safari park, and the National Trust's Stourhead.