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John Humphries House

Situated at the north end ofStockwell Street, London,near the centre of historic Greenwich,John HumphriesHouse was a pioneer computer centre, one of the veryfirst set up for local authority use. Built for the LondonBoroughs'Joint Computer Committee, it was opened in1963. Leo was the world's first business computer, anda Leo III computer was installed here, only the fourthLeo III to be built. Leo stands for Lyons ElectronicOffice. Perhaps surprisingly, the world's first businesscomputer was developed in England by a caterer,J.Lyons & Co.

J. Lyons had numerous tea shops in the Londonarea and beyond. Food was prepared centrally anddelivered to the branches by motor van. Fluctuations inthe weather meant that orders for the tea shops couldchange rapidly - for instance, more salads and less meatpies were required if a warm spell suddenly occurred.Food was being wasted, and an electronic system ofstock control and delivery was particularly attractivefor Lyons. Reduction in office expenditure was also anincentive.

It thus came about that in the late 1940sJ. Lyons& Co took the bold step of developing their owncomputer, the Leo, in conjunction with the Universityof Cambridge. LEO I was ready for work in 1951 andran its first business application, BakeryValuations, as

a test programme on 5 September 1951. LEO took overBakeryValuations completely on 29 November 1951: aworld first.

In 1954 Lyons formed LEO Computers Ltd tomanufacture and market their computers, and thedevelopment of LEO II was started. The first LEO III,a solid-state machine, was completed in 1961. Thesesuccessful computers were manufactured from 1962 to1969, and nearly a hundred were made. Some of themcontinued in commercial use until 1981. In the mid- tolate 1950s even large companies such as Ford UK didnot have their own computer, and it was common tohire time on the few that did exist, such as the earlyLeos.

The use of computers also attracted the attentionof local authorities.John Henry Humphries hadjoined Greenwich Council in 1934 and rose rapidlyfrom Assistant Borough Treasurer to Deputy BoroughTreasurer and then Borough Treasurer in three years.By 1960 computer developments had become familiarto him, but it was then not economic for a borough to

acquire its own computer and outsourcing was generallyresorted to.

A number of southeast London local authoritiespooled services and resources to increase efficiency.

John Humphries pioneered the creation of ajointcommittee formed from the then MetropolitanBoroughs of Greenwich, Woolwich, Deptford,Southwark, Bermondsey and Camberwell, and this inturn set about the creation of a computer centre.JohnHumphries was one of the key figures in the formationof the London Boroughs'Joint Computer Committee.

Contractors for the construction of the building forthe new computer centre were appointed inJuly 1962.G. E. Wallis and Sons of the Strand had successfullytendered for the building at a cost of fl04,762. TheLEO III computer cost f202,008. It was installed andstarted work in February 1963. Unfortunately,JohnHumphries did not live to see the new computerbuilding open. He died in 1962 at the age of 58. As atribute to his energy and initiative the new computercentre was named after him. The LEO III computer was

in use atJohn Humphries House until 1975.A major change took place in 1965 when local

government in London was reorganised.JohnHumphries House then carried out data processingfor the London Boroughs of Bexley, Greenwich andSouthwark. As computing developed, it becamefinancially viable for each local authority to have its owncomputer and the need for ajoint installation ceased.

The use ofJohn Humphries flouse for computingwasdiscontinued. The building now stands empty, andis due to be demolished shortly to make way for theUniversity of Greenwich new School of Architecture.

Rnbert Can

History Speaks

The purpose of this short article is to explore the'wisdom of the ancients' byjuxtaposing insightsabout structural form made by modern architects andengineers with comparable understanding found inbuildings and other structures before the IndustrialRevolution and before the development of what is

considered the modern science of mechanics andengineering. The idea is to discuss a different case

study in each issue of the CHS Magazine. Readers areencouraged to share their observations and to suggestnew cases studies.

22 CHsMagazine

Case Study 1: Vaults with Variableor Multiple Curvatures

As a modern example, I have selected the visuallystunning Gaussian culves used by the Uruguayanengineer and architect Eladio Dieste (1917-2000) inmany of his reinforced brick roofs. For Dieste, theuse of a Gaussian curve provided a solution to theproblem of flexure and hence deformation of wide-spanning transverse barrel vaults, to which he gave thestructurally advantageous catenary profile. He rejectedthe traditional approach of stiffening vaults withribs, arguing that they obstructed and complicatedconstruction when placed underneath and, whenpositioned above, tended to cause fractures at theirjuncture with the vault surface.

To obviate these drawbacks, Dieste decided to givehis roofs a double culvature. And to avoid havingto use massive supports, he made that cur-vature inthe longitudinal direction 'variable', as he put it,with 'a maximum in the keystone to zero against thesupporting elements at the edge', permitting him tomake economical supports 'with a thickness as smallas that of the vault itself.' In addition to the benefitsof its constantly changing profile, the Gaussian curvepresents the structural advantage ofpositive andnegative signs - convex and concave curves - along itssurface.

The general principle contained within Dieste's

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lesson consists in the complexity of cunature thatstiffens a vault. This principle was recognised byPhilibert de I'Orme, architect to the king andsuperintendent of royal buildings under Henri II. Fourhundred years before Dieste, de 1'Orme explainedthat when designing a vault, one strengthens it bycombinins different curyes: 'You can add still moreculyes, as many as you wish', he wrote in his LesNouvelles Inventions pour Bien Bastir et ) Petite Fraiz(1561). 'The more there are, the stronger the form.'De l'Orme was proud of how he integrated togetherthree different tlpes of vaults to support the horseshoe-shaped stairs at the Royal ChXteau ofFontainebleauand at Diane de Poitier's ChXteau dAnet (c.1550),where the horseshoe was given the shape of a lunarcrescent to symbolize the patron's conceit as theOlympian goddess Diana. This combination ofconcave, convex and inclined geometries is a fittineprelude to Dieste's later invention.

A still earlier application of this principle can befound in the vaulting of Saint-Hilaire, Poitiers, whichtook place in the early twelfth century when thereplacement of a timber roof with stone vaults over anexceptionally wide nave prompted a series of designdecisions first to mitigate thrust and then to braceagainst it. I suspect that the weakness of the walls,constructed with small stones known as moellons, andpossibly rubble, prompted the ingenious three-partsolution: ( i) the choice to vault the nave with what

f)er

the great engineer Auguste Choisy termed 'polygonalcupolas with little thrust'; (2) the construction of adetached internal line of piers that were linked to thenave walls by three levels of round arches, whose strongbracing effect, along with their beauty, was admiredby Choisy; (3) vaulting with a complex surface ofundulating curves achieved through the combinationof large and small groin vaults, both in the side aislesand in the space between the internal line of piersand the nave walls. Each side aisle combines one largepartial groin vault with two smaller partial groin vaultsin alternating fashion, the former spanning the entirebay, and the later springing from an intermediary free-standing column.

The groin vaults of the one original bay rhat stillstands, slightly irregular in form and covered withplaster, suggest that these aisle vaults were constructedin moellons, rubble, or a combination of the two. Herewe find the same basic structural principle that was laterarticulated by de l'Orme and subsequently by Dieste,who each applied that lesson in original and inimitableforms, the former in heavy ashlar stereotomic vaults,the latter in light, reinforced brick vaults. All threeexamples illustrate the principle of imparting rigiditythrough what Dieste called 'wave-like curvature'.

RichardA. Etlinretlin@umd.edu.

Saint-Hilaire, Poititrs: Viar of the sidc aisk showingpartialgroin aaults, erected in the tuelfth century, consolidated in the

nineteenth. A small portion of the freestanding bracing pi.ers

and the polygonal cupolas oaer the naue caru be glimpsed beyond(photo by RichardA. Etkn).

Fleischbriicke, Nuremberg

Everyyear since 2007 the GermanBundesingenieurkammer (Federal Chamber ofEngineers) has honoured an outstanding historiccivil engineering structure in Germany with the title:'Historisches Wahrzeichen der Ingenieurbaukunstin Deutschland' ('Historical Engineering Landmarkin Germany'). So far ten buildings and engineeringstructures have been honoured, including the world'sIargest brick-built bridge, the Goltzsch Viaduct (built1846-51); the Stuttgart Television Tower of 195L5;the world's first offshore building, the 'Red Sand'Lighthouse, erected in the North Sea in 1880-5, 1lkm offthe Island of Wangerooge; and Berlin-Tempelhof Airport(1e35-41).

A recent addition to this list of distinguished historicengineering works is the sixteenth-century Fleischbriicke(Meat Bridge), Nuremberg, which received the title inJune this year. The most important stone arch bridgeof the late Renaissance in Germany, the Fleischbriickewas erected in 1596-8 over the Pegnitz River. Foundedon2,123 wood piles, the bridge consists of one flat archspanning 27 metres. The horizontal thrust of the arch istaken up by 400 of these wood piles, which were drivendiagonally into the soft ground. The bridge was builtso robustly that it withstood the healy bombardment ofNuremberg during World War II, and survives to this dayalmost completely intact.

For more information on the Fleischbrrickeand the project 'Historisches Wahrzeichen derIngenieurbaukunst in Deutschland' visit:wvwwahrzeichen.ingenieurbaukunst.de

Email from Patricia Reynolds

On holiday on St. Helena (South Atlantic) this summer Iwas intrigued by the prefabricated iron Market building.Hugh Crallan, in his Island of St. Helena: Listing andPreser-vation of Buildings of Architectural and HistoricInterest (197 4) notes: A very interesting example of earlycast iron technology, imported after the termite attack.Curious gutter brackets (or roofsupports?) not beingused as intended. Iron trussed roofdoes not appear to fitdesign, but must surely be original?'

The building includes cast panels marked 'Gwynne& Co. London', and a notice on the building gives thedate as 1865. Gwynne & Co. are not, as far as I can tell,known as manufacturers of prefabricated buildings,but are known as pump manufacturers. I wonder if theymade structures such as this to house pumping engines. Iwould be interested to know of other Gwynne buildings.

Patrici.a Rqnoldspat@caerlas.co.uk

26 CHS lvlagazine