Liquid Air was the brand name of an unusual automobile

Automobile

An automobile, autocar, motor car or car is a wheeled motor vehicle used for transporting passengers, which also carries its own engine or motor...

 produced by a joint American

United States

The United States of America is a federal constitutional republic comprising fifty states and a federal district...

/English

England

England is a country that is part of the United Kingdom. It shares land borders with Scotland to the north and Wales to the west; the Irish Sea is to the north west, the Celtic Sea to the south west, with the North Sea to the east and the English Channel to the south separating it from continental...

 concern between 1899 and 1902.

The first factory opened in Boston, Massachusetts in 1899, and its owners claimed that they could construct a car that would run a hundred miles on liquid air

Liquid air

Liquid air is air that has been cooled to very low temperatures so that it has condensed to a pale blue mobile liquid. To protect it from room temperature, it must be kept in a vacuum flask. Liquid air can absorb heat rapidly and revert to its gaseous state...

. By 1901 the company had gone into receivership. In 1902 the product was demonstrated by its designer, Hans Knudsen, at a show in London

London

London is the capital city of :England and the :United Kingdom, the largest metropolitan area in the United Kingdom, and the largest urban zone in the European Union by most measures. Located on the River Thames, London has been a major settlement for two millennia, its history going back to its...

; apparently the automobile that was shown was a modified Locomobile

Locomobile

The Locomobile Company of America was an automobile manufacturer founded in 1899. For the first two years it was located in Watertown, Massachusetts, but production was transferred to Bridgeport, Connecticut during 1900 where it remained until the company's demise in 1929...

 steamer. Here it was claimed to run 40 miles (64.4 km) at 12 mi/h on 18 US gal (68 l; 15 imp gal) of liquid air, sold at a shilling

Shilling

The shilling is a unit of currency used in some current and former British Commonwealth countries. The word shilling comes from scilling, an accounting term that dates back to Anglo-Saxon times where it was deemed to be the value of a cow in Kent or a sheep elsewhere. The word is thought to derive...

 a gallon

Gallon

The gallon is a measure of volume. Historically it has had many different definitions, but there are three definitions in current use: the imperial gallon which is used in the United Kingdom and semi-officially within Canada, the United States liquid gallon and the lesser used United States dry...

.