At the outbreak of the Second World War, H.M Nautical Almanac Office (HMNAO), which had recently become part of the Royal Observatory, was evacuated to Bath. It remained in Bath until 1948, when it relocated to the Observatory’s new home at Herstmonceux.
When the Royal Observatory was founded in 1675 and John Flamsteed appointed by King Charles II as his ‘Astronomical Observator’, he was given the instruction ‘to apply himself with the most exact Care and Diligence to the rectifying the Tables of the Motions of the Heavens, and the places of the fixed Stars, so as to find out the so much desired Longitude of Places for perfecting the art of Navigation.’
Some 91 years later, the fifth Astronomer Royal Nevil Maskelyne achieved this long sought objective with the publication of the Nautical Almanac in 1766. When used with the simultaneously published Tables Requisite, it allowed a sailor at sea to navigate using the celestial bodies.
The Board of Longitude was responsible for overseeing the production of annual editions of the Almanac until 1828. In practice, it was the Astronomer Royal who carried this responsibility and oversaw production until 1818 when responsibility passed to Thomas Young, the holder of the new post of Superintendent of the Nautical Almanac, who reported to the Board. Young was succeeded in 1829 by John Pond, the Astronomer Royal. Pond was rapidly followed in 1831 by William Stratford. It was Stratford, who in 1832, set up the Nautical Almanac Office (NAO) to oversee the Almanac’s production, with the Superintendent now reporting to the Admiralty. Click here for a full list of the Premises of (HM) Nautical Almanac Office since its creation in 1832
In early 1937, HMNAO as it had by then become known, became part of Royal Observatory at the instigation of the Astronomer Royal following the suspension and subsequent dismal of Comrie its Superintendent in 1936. It remained part of the Observatory until the Observatory’s closure in 1998. It is currently based at the United Kingdom Hydrographic Office, Taunton.
In August 1939, HMNAO moved from the Royal Naval College in Greenwich where it had been since 1922, to Devonport House between the College and Greenwich Park. A few weeks later, the Second World War began. With boxes still unpacked, HMNAO was given orders to join the Hydrographic Department at the Admiralty’s evacuation headquarters in ‘town AA9’. Although the staff didn’t know it at the time, this turned out to be City of Bath.
Towards the end of September 1939, HMNAO with its twenty or so staff moved into Laggan, a large house in extensive grounds in College Road, Bath. Laggan was shared with the Hydrographic Department and also housed the Assistant Hydrographer, the Tides Department, and the Superintendent of Sailing Directions and his staff.
In addition to the routine calculations and proof-reading involved in the preparation and printing of the almanacs, the Office also took on other duties. These included both astronomical work such as supplying black-out times to the BBC, the newspapers and the BBC and non-astronomical work such as the computation of Bomb Ballistic Tables. The work of the Office was disrupted in 1940 when Hammond’s printing works where the almanacs were printed was bombed in early November. The ensuing fire destroyed all the bespoke type and plates, along with some original copy (of which no backup existed). This affected the typographical appearance of the publications for several years as well as contributing to a delay in their printing.
Elsewhere in Bath, purpose built hutments were under construction for the Admiralty, at Foxhill, Ensleigh and Warminster Road.
In all, five blocks were constructed at Ensleigh. Built by Laing, each consisted of a single story building based on a long central corridor from which spurs sprouted off on either side – six to the left and six to the right. They are located high above the centre of Bath at the top of Lansdown Hill. HMNAO transferred to Block E of the Ensleigh hutments, in November 1941. Block E was the most easterly of the blocks and was entered from Granville Road. HMNAO remained at Ensleigh until October 1949, when it moved to Herstmonceux.
Laggan (which was originally called The Limes), has been renamed Laggan House. It is divided into seven private flats. Although the grounds remain extensive, a substantial portion were carved off to create the Laggan Gardens estate in the 1990s. The hutments at Ensleigh however no longer exist. In 2011, just a few days after the above photo was taken, the BBC reported that the site would be closing, a fact that was later confirmed by the Ministry of Defence on 7 July 2011. In April 2012, the south part of the site containing Block E was sold to Skanska Residential for £3.9 million. Planning permission for its redevelopment as housing was granted in 2013. In 2014, the site was sold on for £8 million. Still standing in July 2013, the Block E hutments had been demolished and the site cleared by the spring of 2014 with the last of the new buildings being completed in 2020.
HMNAO relocated from Bath to the Observatory’s new home at Herstmonceux in 1948, and then to Cambridge in 1990. When RGO was closed down in 1998, HMNAO was transferred to the Rutherford Appleton Laboratory. In December 2006, it was transferred again, this time to the United Kingdom Hydrographic Office.
Donald Sadler has written extensively about the Bath years in Part 3 of his volume A Personal History of H.M. Nautical Almanac Office. This should be consulted for further information.
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