Prior to 1957 when the first “electronic” computer, the Datatron, was acquired by AECL, important physics and reactor calculations were carried out by a “Calculation Group” with a number of mechanical calculators. Arden Okazaki, who worked in this group, recalls that there were three different manufacturers of these mechanical wonders – Marchant, Hughes-Owens and Friden. The Datatron, which was an electron-tube based computer, represented a major step in the calculating abilities of the laboratory and the calculators were quickly phased out. Some survived as curiosities into the 1970s and Mike Milgram recalls sending one of them into a never-ending loop by accidentally asking it to divide by zero.
Until recently the only trace of these calculating machines the Society for the Preservation of Canada’s Nuclear Heritage Inc. (SPCHNI) has been able to find has been a photo showing three prominent Chalk River physicists (John Kuehner, Allan Bromley and Einar Almquist) in front of a rack of counting equipment and having a Marchant calculator on their table as their only calculating device.
A recent “garage sale” at the local St. Barnabas church however produced a great surprise – a Friden, Model STW10, electric-powered calculator available at the grand price of $1.00. Arden Okazaki was able to confirm that just such a model was used at Chalk River. (The next version, the Model SRW, was a more advanced unit able to calculate square roots of numbers – the CRNL models did not).
The initial assumption was that the Friden calculator had a CRNL origin and has been sitting in a local basement for many years. However, a small tag attached to one side of the unit reads ” US Navy Property”. Further investigation has revealed that the calculator was purchased at a garage sale in Pembroke several years earlier by Orville Miller and had been sitting in the St. Barnabas basement collecting dust until the recent sale.
How did a calculator, originally belonging to the US Navy, arrive in the Ottawa valley? Several possibilities exist. AECL did a number of tests with nuclear fuel that was used in the US nuclear submarine program. US personnel were stationed at the laboratory for these tests. In addition, there was a US Liaison Office at CRNL, staffed by a number of US personnel, for an extended period. Did the US group have a need for a calculator which was then sold locally when it became surplus? Another possibility is that members of the US Navy, which included future President Jimmy Carter, brought the machine with them to perform some calculations on radiation doses when they helped with the clean-up after the 1952 incident in NRX.
The Society hopes that there may be someone who may be able to shed some light on the history of this Friden calculator which now occupies a space in the storage facility next to the control console of its successor, the Datatron. Please contact Jim Ungrin at 613 584 3055 or ungrinjr@gmail.com if you can help. In addition, we have succeeded in downloading from the internet a copy of the service manual for the device and would love to have a volunteer who would accept the challenge of reviving the unit to its glorious past working condition.
