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The Annexe Story


The Problem : By 1940 World War II was at a critical stage and the Allied Forces faced a looming crisis - a shortage of weaponry. Supplies of arms were sought to replace what had been lost during the battles against the Germans in North Africa. Australia could manufacture artillery for the field, but they were useless without vital gun sights with their specialised optical components. Prior to the War these ‘dial’ sights had been made in the UK, though not in large numbers and the German navy were now blocking supply. Making the sights required specialised equipment and expertise – also in short supply.

The Call : In July 1940, the Australian government called on universities to urgently research the design and manufacture of the much-needed optical components. Professor AL (‘Leicester’) McAulay, Head of the University of Tasmania’s Physics Department, immediately discussed the request with Dr FD (‘Fletcher’) Cruikshank (Senior Lecturer in Physics) and Mr EN (‘Eric’) Waterworth (local instrument maker and mechanical object designer). At his next physics lecture McAulay asked his third year students to help and five volunteered – Harry C Lewis, Wilf T Robinson, Gavin A Hills, A Geoff Fenton and Vic N Fitze. With Cruickshank as their deputy, McAulay and Waterworth led this new team of five loyal and hard-working physics students who spent half their working week on this unpaid research work. The rest of their time was spent in lectures and study in preparation for their final November exams.

The Challenge : The team had to produce precision instruments of a quality that surpassed those from other Allied countries, with no experience and no one in Australia to train them. They started from scratch – firstly to research, design and produce their own tools and machinery, improvising with what was locally available. They then had to source the glass and prepare, cut, grind and polish it to produce lenses and prisms, make the metal fittings and then assemble the sights.

Existing optical designs were not able to be used since components and even optical glass had become unavailable in Australia due to the War. They first had to convert raw window glass to lens-quality glass blocks by annealing in a home-made furnace. The key task of polishing optical glass surfaces, later done by machine, was initially done by hand. The tolerances demanded were incredibly tight. For the prisms, flat surfaces had to be within 5 millionths of an inch per inch – the width of two human hairs every kilometre! Roof prisms had to have angles accurate to within two seconds of arc – or one 1800th of a degree! And these seemingly impossible standards had to be achieved with only home-made equipment.

The Team : Work was loosely divided into three parts. The first two teams worked on the precision glass work – McAulay, Lewis, Robinson and Fitze researched prism manufacture, while Cruickshank and Hills explored techniques for producing spherical surfaces. Waterworth was a successful inventor and the proprietor of a Tasmanian instrument-making business. He immediately became the team’s mechanical authority. He designed the machinery and tools required to cut and grind the glass. Later, the team was joined by biophysicist (and etymologist) turned accountant, Brian Plomley who worked at the Annexe from June 1941 until 1944. Ernest Bessell took over as accountant after Plomley. 


The First Prisms : In February 1941 the team were asked to try and produce roof prisms, a notoriously difficult task. Waterworth’s early machines for making prisms included spindle-polishing machines, metal try squares, micrometers, ‘laps’, a glass cutting saw and a grinder for shaping the prism blanks. He designed novel glass cutting methods and bespoke jigs. The working conditions for the team were primitive. Many of the early machines were made by Waterworth in his home shed, while the university staff and students worked in an earth-floor shed on the Domain Campus. By late Winter 1941 the team, along with about ten girls who’d just finished school, established a production line making roof prisms.

The Test : The first six prisms were ready in September 1941 and were sent to the University of Melbourne for an acceptability interferometer test – the team were tense. In Mid-October the result came back – a major success! Four prisms passed with flying colours while the remaining two required only minor correction. The decision to proceed to large scale manufacture was made on these results.

The Arrangement : The Government would provide the building and equipment as requested by McAulay, with Waterworth managing the operation on a cost-recovery basis. This unusual arrangement meant that Waterworth had to be reimbursed monthly. With demand for optical components growing even more critical, the proposal was immediately accepted. In November 1941 the construction of the ‘Optical Munitions Annexe 9/101’ – ‘The Annexe’ – was approved by the Australian Ministry of Munitions. 

The Annexe - The Unknown : Drawings for the Annexe design were approved and a construction contract signed on-site on Christmas Eve 1941. The single-storey Annexe was completed four months later. Decisions also had to be made about equipment and machinery. All of this while the number of lenses and prisms needed for the war was unknown, as was the range of other products that they would later need to research, design and produce.


The Staff : Four lead team members, each with their own area of responsibility, were involved from before the Optical Munitions Annexe was constructed and stayed on until the end of the War. They were McAulay, Cruickshank, Waterworth and Mr PH (‘Philip’) Waterworth an optometrist and one of Eric's brothers. 

From the start at least 150 staff were needed. McAulay had firm ideas about the type of staff he wanted and oversaw all recruitment. For new staff the immediate ‘on the job’ training in making prisms was not easy. Most training was done by three of McAulay’s physics students – Fitze, Lewis and Robinson. According to Fitze, “basic things like using a try square or micrometer had to be taught. Skills like smoothing a piece of glass with emery powder and water and then polishing on a pitch lap using rouge and water, correcting imperfections on the surfaces, and interpreting interference patterns all needed intensive training.”


The Space : Within three months of construction, space in the Annexe was already tight. Two shifts per day were introduced (7.15am-3.15pm and 3.15pm-11.15pm).  At peak production by mid-1943, more than 210 staff, mostly women, were employed at the Annexe working in three shifts per day. A second storey and a canteen were hastily added to meet the needs of expanded production.

The Fifth Column : From commencement of operations, Commonwealth security officers guarded all Annexe doors. They were deployed because of concerns about ‘The Fifth Column’ of potential spies and saboteurs who might infiltrate The Annexe. The Sydney publication ‘Smiths Weekly’, a patriotic tabloid, claimed that Australia “has one of the biggest fifth columns in the world” (14 Feb 1942). The hear of infiltration figured strongly in the popular and military imagination, but ultimately proved to be largely unfounded.


The Achievement : The Annexe produced more than 17,000 prisms for the war effort between 1941 and 1945. The largest roof prism they made was used in the Kerrison Predictor, one of the first fully automated anti-aircraft system telescopes.

The Lens : By 1942 the Annexe was also making photographic lenses for the RAAF for reconnaissance cameras, binoculars, guns and bombsights and telescopes. The design and production of lenses diversified as the war progressed  with many lenses built from multiple components. This work involved laborious ray tracing of all lens surfaces, to an accuracy of up to 10 decimal places using 10-figure logarithms. In a simple, four-component lens there are seven curvatures, four thickness and three air spaces, all of which may vary. Every time a change was made a new ray tracing had to be made – incredibly time-consuming. Lenses designed, prototyped and tested at the Annexe during World War Two included gun and bomb-site lenses, camera and binocular lenses, copying lenses, projector lenses and telephoto-camera lenses. The workshop responsible for ensuring every lens was checked and mounted correctly was managed by WA (‘Bill’) Perkins.


The End of the War : By the end of the war, three key assets had been developed :

1. A team of skilled and experienced workers and former physics students highly trained in scientific and technical methods.

2. Australian experience in the techniques of precision glass working and instrument making.

3. Unique and highly valuable mathematical methods of optical design.

But what next? This skilled team needed to find a new purpose at war’s end. Neither the team leaders nor the workers – especially the now highly skilled women, wanted to merely pack up and go home to the life they had before. A new venture was needed.

A New Purpose - The Waterworth Slide Projector and Camera Lenses : Within two years of the end of the war there was a national move in education departments to employ visual technoloiges as an adjunct to teaching for use in schools throughout Australia. The Annexe team quickly moved into this new peacetime research and production area.

By 1947 a new business called ‘EN Waterworth’ was set up with Victor Fitze as production manager, the original Annexe team on board, and many of the women who’d worked in the wartime Annexe re-employed. The business remained on the Domain Campus until the early 1960s then moved into a renovated factory space in Warwick Street, Hobart. Before long this new peacetime activity was producing over 200 sets of projection lenses per month. A ‘set’ comprised nine large lenses and the associated metal mounts. The Waterworth Slide Projector became the Australian standard for slide projection from the late 1940s to the 1960’s, due to its practical, robust and quality design and high optical performance. The range of projectors was impressive and included projection systems for strip film. Much of the research into the type of materials, machining, lens coatings and electrics was once again done in collaboration with the University’s Physics Department, based on the successful relationship forged during the war years.

At the same time the EN Waterworth business was producing a large quantity of quality 50 mm f/3.5 photographic lenses for miniature cameras. Small aperture lenses of the same type were produced for darkroom enlargers. Up to 40 camera and enlarger lenses were produced per month, along with their mounts and frames. The business also produced one process lens and prism per month. A full department within the business was dedicated to the repair and coating of lenses with a non-reflective film. Lens repair orders came from all over Australia, NZ and Fiji.

The business continued manufacturing a diverse range of optical instruments and components including large astronomical telescopes, until the early 1970s. When the Waterworth factory was finally closed and sold up, the team spirit lived on. Regular yearly and five yearly gatherings of the predominantly female Annexe team persisted into the 1980s to celebrate and reminisce their remarkable achievements.