National Physical Laboratory (United Kingdom)

Precursors

In the 19th century, the Kew Observatory was run by self-funded devotees of science. In the early 1850s, the observatory began charging fees for testing meteorological instruments and other scientific equipment. As universities in the United Kingdom created and expanded physics departments, the governing committee of the observatory became increasingly dominated by paid university physicists in the last two decades of the nineteenth century. By this time, instrument-testing was the observatory's main role. Physicists sought the establishment of a state-funded scientific institution for testing electrical standards.[4]

Founding

The National Physical Laboratory was established in 1900 at Bushy House in Teddington. Its purpose was "for standardising and verifying instruments, for testing materials, and for the determination of physical constants".[5] The laboratory was run by the UK government, with members of staff being part of the civil service. It grew to fill a large selection of buildings on the Teddington site.[6]

Late 20th century

Administration of NPL was contracted out in 1995 under a Government Owned Contractor Operated (GOCO) model, via a new operating company, NPL Management Ltd. Serco won the bid and all staff transferred to their employment. Under this regime, overhead costs halved, third-party revenues grew by 16% per annum, and the number of peer-reviewed research papers published doubled.[7][8]

NPL procured a large state-of-the-art laboratory under a Private Finance Initiative contract in 1998. The construction was undertaken by John Laing.[9]

21st century

The new laboratory building, which had been maintained by Serco, was transferred back to the DTI in 2004 after the private sector companies involved made losses of over £100M.[9]

It was decided in 2012 to change the operating model for NPL from 2014 onwards to include academic partners and to establish a postgraduate teaching institute on site.[10] The date of the changeover was later postponed for a year.[11] The candidates for lead academic partner were the Universities of Edinburgh, Southampton, Strathclyde and Surrey[12] with an alliance of the Universities of Strathclyde and Surrey chosen as preferred partners.[13]

Funding was announced in January 2013 for a new £25M Advanced Metrology Laboratory that will be built on the footprint of an existing unused building.[14][15]

NPL Management Ltd and the operation of the laboratory transferred back to the Department for Business, Innovation and Skills (now the Department for Science, Innovation and Technology) on 1 January 2015.[16]

Atomic clocks

The first accurate atomic clock, a caesium standard based on a certain transition of the caesium-133 atom, was built by Louis Essen and Jack Parry in 1955 at NPL.[25][26] Calibration of the caesium standard atomic clock was carried out by the use of the astronomical time scale ephemeris time (ET).[27] This led to the internationally agreed definition of the latest SI second being based on atomic time.[28]

Computing

Early computers

NPL has undertaken pioneering computer research since the mid-1940s.[29][30][31] From 1945, Alan Turing led the design of the Automatic Computing Engine (ACE) computer.[32] The ACE project was overambitious and floundered, leading to Turing's departure.[33] Donald Davies took the project over and concentrated on delivering the less ambitious Pilot ACE computer, which first worked in May 1950. Among those who worked on the project was American computer pioneer Harry Huskey. A commercial spin-off, DEUCE was manufactured by English Electric Computers and became one of the best-selling machines of the 1950s.[33]

Packet switching

Beginning in the mid-1960s, Donald Davies invented and pioneered the implementation of packet switching, now the dominant basis for data communications in computer networks worldwide.[34] Davies designed and proposed a national commercial data network in his 1965 Proposal for the Development of a National Communications Service for On-line Data Processing.[35] Subsequently, the NPL team, led by Roger Scantlebury, were the first to implement packet switching in the local-area NPL network in early 1969,[36][37][38][39] which operated until 1986. They carried out work to simulate the performance of a wide-area packet-switched network capable of providing data communications to most of the U.K.[40] Their research and practice influenced the ARPANET in the United States, the forerunner of the Internet, and other researchers in the UK and Europe, including Louis Pouzin, as well as in Japan.[41][42][43]

NPL sponsors a gallery, opened in 2009, about the development of packet switching and "Technology of the Internet" at The National Museum of Computing.[44][45][46][47]

Internetworking

NPL internetworking research was led by Davies, Derek Barber and Scantlebury, who were members of the International Network Working Group (INWG).[48][49] They observed that connecting heterogeneous computer networks creates a "basic dilemma" since a common host protocol would require restructuring the existing networks. To study this, NPL connected with the European Informatics Network (Barber directed the project and Scantlebury led the UK technical contribution)[50][51][52] by translating between two different host protocols; that is, using a gateway. Concurrently, the NPL connection to the Post Office Experimental Packet Switched Service used a common host protocol in both networks. NPL research confirmed establishing a common host protocol would be more reliable and efficient.[53] The EIN protocol helped to launch the proposed INWG standard.[54] Bob Kahn and Vint Cerf acknowledged Davies and Scantlebury in their 1974 paper "A Protocol for Packet Network Intercommunication".[55] Barber was involved in Internet design discussions in 1980.[56]

Scrapbook

Scrapbook was an information storage and retrieval system that went live in mid-1971. It included what would now be called word processing, e-mail and hypertext, anticipating many elements of the World Wide Web.[57] The project was managed by David Yates who said of it "We had a community of bright people that were interested in new things, they were good fodder for a system like Scrapbook" and "When we had more than one Scrapbook system, hyperlinks could go across the network without the user knowing what was happening".[58][59] It was decided that any commercial development of Scrapbook should be left to industry and it was licensed to Triad and then to BT who marketed it as Milepost and developed a transaction processor as an additional feature. Various implementations were marketed on DEC, IBM and ITL machines. All NPL implementations of Scrapbook were closed down in 1984.[60]

Email

Derek Barber proposed a network mail protocol and implemented it on the EIN in 1979, the first European implementation of electronic mail.[61][62] Jon Postel referenced Barber's work in his first paper on Internet email, published in the Internet Experiment Note series.[63]

Secure communication

In the early 1990s, the NPL developed three formal specifications of the MAA: one in Z,[64] one in LOTOS,[65] and one in VDM.[66][67] The VDM specification became part of the 1992 revision of the International Standard 8731–2, and three implementations in C, Miranda, and Modula-2.[68]

Electromagnetics

A 2020 study by researchers from Queen Mary University of London and NPL successfully used microwaves to measure blood-based molecules known to be influenced by dehydration.[69]

Metrology

The National Physical Laboratory is involved with new developments in metrology, such as researching metrology for, and standardising, nanotechnology.[70] It is mainly based at the Teddington site, but also has a site in Huddersfield for dimensional metrology[71] and an underwater acoustics facility at Wraysbury Reservoir near Heathrow Airport.[72]

Timing

The National Timing Centre (NTC) Programme has been developed to provide a time infrastructure system for research and technology.[73] In 2025, £68 million was awarded to the National Physical Laboratory to further develop the NTC.[74]