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The story behind the Tellurometer story

by Mary Wadley von Hirschberg

It is now more than 50 years since the survey world was startled and revolutionised by the invention of the Tellurometer by Trevor Lloyd Wadley. A new book " Trevor Lloyd Wadley – Genius of the Tellurometer" provides a look at the character of the inventor and outlines the circumstances under which the invention was born.

On 9 November 1958, the New York Times reported that through the use of the Tellurometer it had suddenly become possible for two men to measure the island of Manhattan in three-and-a-half hours, whereas previously it would have taken four men, five days with traditional surveying methods. Actual measuring time took only one hour; the remaining two-and-a-half hours were required by the man in the field to travel from the island’s southern to northern tip! “Using the top of the Empire State Building as the master transmission point, the high-speed microwave system known as the Tellurometer showed Manhattan measuring 13,08 miles in length.”

In the spring of 1957, Wadley had arrived in England to carry out measurement trials of the Tellurometer on the so-called Ridgeway Base. These trials were extremely successful. He presented a paper on his instrument at the Royal Geographical Society in London and was given a standing ovation by delegates from all parts of Europe. After the trial at the Ridgeway demonstration, inquiries came from all over the world and several thousand copies of Wadley’s paper were sent to Europe alone.

In due course reports came in from across the world – from the Arctic, Australia and Malaysia – over 48 countries, describing feats of survey that had previously been impossible, or that suddenly involved hugely reduced costs. Over 20 000 Tellurometers were produced in Cape Town and distributed worldwide under the patent for the Tellurometer held by the South African Council for Scientific and Industrial Research (CSIR). Eventually production was taken over by Plessey, South Africa.

Trevor Lloyd Wadley, the inventor of the Tellurometer, was born in 1920 in Durban, lived all his life in South Africa, but travelled overseas both during World War 2 and later in relation to his inventions. As his sister, I have recorded the story of my brother at this late stage of my life, finally convinced that it had been left to me to tell the whole unvarnished story. Nobody in the course of 50 years had been able to piece together the various facets of his life, partly due to his early demise and partly to his intensely private and modest nature. Even his older siblings did not really understand the importance of his work, and, although he enjoyed the company and support of his colleagues, few people knew the details of his private life.

Coupled with the above facts, the defense of the Allied shipping around the coast of South Africa during the war was conducted largely on a need-to-know basis. This was mainly due to the fact that the decision to enter the war on the side of the Allies was passed by a very small majority in Parliament.

After the war, and from 1948, in which year the Apartheid Government assumed power, it could be expected that achievements emanating from South Africa would have received no sheen of glamour on account of their country of origin. Quite the opposite happened, the major countries of the world acknowledged that South Africa had produced an instrument for measuring land which they had been unable to produce despite years of effort and expense.

In 2001 the MTN Science Centre at the Canal Walk in Cape Town produced an excellent exhibition of all the well-known inventions of South Africa. Star of the exhibition was the Tellurometer, supported by myriad newspaper cuttings furnished by Tellumat which still produces Tellurometers in their factory in White Road, Plumstead. This exhibition encouraged me to pursue the idea of a biography of my brother, Trevor.

My sister, Cynthia, and I were shown around the factory and were introduced to several employees who had worked there when Wadley had been making his regular inspections. The manager in 2001 was Ian Robertson, who was hugely enthusiastic about the prospect of a biography. He was convinced that the engineering electronics network and opportunities presently enjoyed by South Africa stemmed from the production of the Tellurometer. With the support of Brian Sturman from Tellumat, who had rescued many cuttings from the wastepaper baskets over the years, I started on my journey of discovery of the intricacies of all the inventions of my brother, aided by Graham Rodgers, an electronics engineer.

I met Graham at a meeting of the Simon Van der Stel Foundation in Cape Town at about this time. He had had a life-long fascination with the career of my brother and had met him as a student. I also started making a series of phone calls to Gill Wadley, my brother’s widow. These phone calls stretched over a period of years as Gill’s memory and confidence grew.

About three years ago the editor of the Survey Review journal in the United Kingdom, Jim Smith, visited Tellumat in Cape Town. He was interested in telling the scientific history of the Tellurometer. I was introduced to Jim, and from then on we exchanged information with a view to eventually producing some type of record of the work and life of Trevor Lloyd Wadley. Finally, in May this year at a celebration in Cape Town of the 50th anniversary of the production of the Tellurometer, Jim Smith’s book “The Tellurometer: from Dr. Wadley to the MRA7” and my book “Trevor Lloyd Wadley – Genius of the Tellurometer” were launched. It had been decided that the two works be printed separately, since their style of writing and approach were so different, but close co-operation between the two authors was at all stages maintained, skillfully guided by Brian Sturman who eventually also co-authored the scientific book along with Alan Wright from the United Kingdom.

In the personal history my brother’s fascinating character is described through numerous anecdotes. His early development as one of ten children is discussed as are his experiences of college and military service. The Panoramic Adapter for assisting in tracing enemy messages by radio came to light while Wadley was a youthful lieutenant in World War 2. Later his work at the CSIR and related organisations is described, as well as its impact overseas. I have taken care to comment on every invention in detail.

When Wadley attained the degree of D.Sc (Eng.) on 14 December 1959 from the University of the Witwatersrand, his radio receiver was standard equipment in the British Army, Royal Navy and Royal Air Force. This famous Wadley-Loop Radio was conceived during the earliest years of Schonland’s CSIR, and produced by the Racal company in England under licence to the CSIR. In 1954 it was regarded as one of the greatest advances in high quality receivers in the preceding 20 years. Later came the Barlow-Wadley receiver after Wadley had left the CSIR and had moved to Warner Beach in Natal.

The book describes the largely unheralded work of the Special Signals Services (SSS) along the coast of South Africa during the war, and Wadley’s contribution to its radar development. When the Allies invaded southern Europe, the military command asked for SSS technicians from South Africa to accompany General Alexander’s forces to supply various specialised services. The SSS also staffed active field radar stations in the campaign.

On 12 February 1979 the Postal Authorities of South Africa issued in Pretoria (the administrative capital) a 15 cent stamp to commemorate the 25th Anniversary of the Tellurometer. It depicts a very clear representation of the Tellurometer on the stamp alongside a profile photograph of the inventor. All members of the South African Institute of Electrical Engineers were presented with a first day issue. But in 1971 the Postal Authorities of Belgium were the first to show the Tellurometer on a stamp, and this was done to mark the 10th Anniversary of the Antarctic Treaty. The Tellurometer MRA2 was depicted there as playing a major role in the topographic surveys which formed an important part of scientific research.

Wadley received the Doctor of Science, Honoris Causa from the University of Cape Town in 1976 and the Frank P. Brown Medal in 1970 from the Franklin Institute of the State of Pennsylvania for Promotion of the Mechanic Arts, situated in Philadelphia in the United States. The previous year the same medal had been awarded to Frank Lloyd Wright of Guggenheim fame.

The book also gives an idea of Wadley’s home life at Warner Beach in Natal and how, for the first year there, he lived at Warner Beach beyond the reach of electricity! To summarise, using the words of the preface to the book: “This is the story of how in 1954, on the tip of Africa, a young eccentric genius invented a quick and easy way of measuring land, a feat that had been attempted for years and at great expense by the major countries of the world without success.

”It describes how the strategic position of South Africa during World War 2 promoted the flowering of an electronics industry in a predominately mining and agricultural country, and how the largely unheralded work of the Special Signals Services in South Africa had to be kept secret even from its members. It is a story of how a dominant mother can damage a gifted child, and examines the criteria for the awarding of bursaries.” It is also a love story.

The indigenous bush of the Burman Reserve above Umgeni River in Natal has now reclaimed the two acres where the old Wadley family residence stood. The four exotic, interlacing Bauhinia trees that once had been the jungle gym of a young inventor, have long since succumbed to the attentions of a zealous horticulturist. Time has closed in on an era, but the story of the Tellurometer will continue to be told as a milestone in man’s ceaseless efforts to master his environment.

Trevor Lloyd Wadley – Genius of the Tellurometer can be ordered from Mary von Hirschberg. Contact Mary Wadley von Hirschberg, This e-mail address is being protected from spambots. You need JavaScript enabled to view it

The cost is R155.00 for postal addresses is South Africa and US$25 for postal addresses outside the country. Details and methods of payment will be advised on application by email. Cost includes post and packaging.