Maull & Polyblank, the image, with arched top mounted on period paper with manuscript title 'F. W. Simms, F.R.A.S.' the the base of the image, depicting a seated gentleman next to a Smith Beck & Beck, No.1 folding microscope with Varly stage, image 155mm x 208mm, in modern card mount Frederick Walter Simms (24 December 1803 – 27 February 1865) was a British civil engineer, known for his association with the Greenwich Observatory. He was the brother of William Simms (1793–1860), who, alongside his partner Edward Troughton formed the company of scientific instrument makers Troughton & Simms. Before joining the Greenwich Observatory in 1830, Simms apprenticed as a surveyor and contributed to the Trigonometrical Survey of Ireland. His tenure at the Observatory began when Thomas Glanville Taylor departed for the Directorship of the Madras Observatory. By 1835, Simms' responsibilities, as listed by John Pond, included observations with the Zenith Tube alongside John Henry Belville, occasional work with other instruments, proofreading printed observations with Henry, and overseeing the publication process of the annual volumes of Greenwich Observations. While Pond commended Simms as "very able and diligent," he also noted irregularities in chronometer rates, which eventually led to expectations of retirement. Despite being paid a modest salary supplemented by earnings from navigation lessons and surveying tasks, Simms found the financial arrangement insufficient. His dissatisfaction culminated in his resignation on 21 October 1835, shortly after the arrival of the new Astronomer Royal, Airy. Airy, in his autobiography, remarked that Simms had hoped for the position of First Assistant, a role for which Airy deemed him unfit. Following his departure from the Observatory, Simms pursued a new career path as a railway surveyor and engineer. In 1836, Simms commenced his role as a resident engineer with the South Eastern Railway Company, embarking on various significant projects, including the construction of the Bletchingley and Saltwood tunnels. He authored several books on surveying and tunnelling and produced the 1838 Map of The Parish of Greenwich in the County of Kent for the Tithe Commissioners. In 1846, the East India Company, seeking to expand railway infrastructure in their territories, approached Simms to serve as their consulting engineer in India. Despite grappling with health issues exacerbated by the climate, Simms briefly sojourned in Mauritius before resuming his duties. Among his responsibilities was overseeing the comprehensive survey and mapping of Calcutta, primarily conducted by local assistants. Upon concluding his tenure with the East India Company, Simms returned to England in 1851, his health notably deteriorated due to the harsh conditions in India. He subsequently retired from active professional life.