Cicely Popplewell

Popplewell was born on 29 October 1920 in Bramhall, Stockport, England.[1] Her parents were Bessie (née Fazakerley) and Alfred Popplewell, a chartered accountant. She attended Sherbrook Private Girls School at Greaves Hall in Lancashire.[2]

She studied the Mathematical Tripos at the University of Cambridge[3][4] where she worked with statistics in the form of punched cards.[3] She was considered an expert in the Brunsviga desk calculator.[5]

She graduated with a Bachelor of Arts degree in 1942, which was converted to a Master of Arts degree in 1949 from Girton College, Cambridge.[6][7]

In 1943 she was a Technical Assistant in the Experimental Department at Rolls-Royce Ltd. and joined the Women's Engineering Society.[4]

In 1949 Popplewell joined Alan Turing in the Computer Machine Learning department at the University of Manchester to help with the programming of a prototype computer.[8][9] At first she shared an office with Turing and Audrey Bates, a University of Manchester mathematics graduate.[10][11] Her first role was to create a library for the prototype Manchester Mark 1.[12] This included input/output routines and mathematical functions, and a reciprocal square root routine.[12] She worked on ray tracing.[12] She wrote the first versions of sections of the subroutines for functions like COSINE.[13] Together they designed the programming language for the Ferranti Mark 1.[14][15]

She wrote the Programmers Handbook for the Ferranti Mark 1 in 1951, reworking Turing's programming manual to make it comprehensible.[16][17] Whilst Turing worked on Scheme A, an early operating system, Popplewell proposed Scheme B, which allowed for decimal numbers, in 1952.[18][19]

Popplewell went on to become an advisor and administrator in the newly formed University of Manchester Computing Service where she was remembered as a 'universally liked' mother-figure.[20] She left the Service in the late 1960s shortly before her marriage.[17]

Popplewell taught the first ever programming class in Argentina at the University of Buenos Aires in 1961.[21][22][23] Her class there included the computer scientist Cecilia Berdichevsky.[21] She was supported by the British Council.[24]

Popplewell published the textbook Information Processing in 1962.[25]

Her life was documented in Jonathan Swinton's 2019 book Alan Turing’s Manchester.[13][26]

In 1969 Popplewell married George Keith Williams in Chapel-en-le-Frith.[27] She died on 20 June 1995 at Stockport Infirmary, Stockport. The funeral service was held on 27 June 1995 at St John's church, Buxton, followed by a private cremation.[28]