2020:389 - Magazine Fort, Phoenix Park, Dublin 8, Dublin

A number of archaeological investigations were carried out at the Phoenix Park Magazine Fort in 2020. This is one of the major surviving magazine forts in the country was constructed in 1736 on the site of the Phoenix House, and extensively remodelled throughout the 19th and 20th centuries.

These concentrated in four areas: (i) the former gardens, (ii) the loose stone stored in the fort, (iii) the existing surfaces of the fort, and (iv) the 20th-century chloride processing plant.

Test-trenches in the former gardens revealed the presence of imported garden soils and traces of garden paths. A large quantity of 19th-century clay pipe within the garden soils indicate that the space was likely used as a recreational area where soldiers were permitted to smoke, unlike the rest of the fort where smoking was prohibited by Magazine Regulations. The findings from the archaeological trenches were combined with historical and cartographic evidence to reconstruct the formal gardens of the magazine fort. These gardens were laid out between 1802 and 1859 in the lower area of the ravelin, and were utilised until the beginning of the 20th century.

The assessment of the loose fragments of masonry distributed throughout the Magazine Fort was to establish whether some or all derived from the fort, and in particular whether any or all of the fragments belonged to the demolished Duke of Dorset gate. The gate was partially demolished in the c. 1980s to allow large vehicles to enter the fort. Many of the gate stones did appear to be present, including the key stone reading MDCCXXXVI (1736), and a gate inscription reading EXTRUCTA IMPER ANTE GEORGIO SECVNDO; REGIS LOCVM TENENTE LIONELLO SACKVILLE; DVCE DORSETIAE (Erected during the reign of George the Second, by the King’s Lord Lieutenant Lionel Sackville, Duke of Dorset - more or less). Many other loose stones were interpreted as parts of railings, gun emplacement, etc., and in some cases identified as not coming from the fort.

The assessment and survey of the existing outdoor surfaces of the fort was conducted in order to identify the materials used in the ground surfaces and to digitally map them to inform the long-term conservation of the fort. Nine surface materials were identified: granite pavements, limestone pavements, cobbles, stone setts, brick surface drains, asphalt/tarmacadam, concrete, cast-iron utility covers, and grass. Small test-pits were excavated through overgrown areas and concrete surfaces to establish the former surface and get information about phasing. A surprising amount of interesting information was gathered.

The physical remains of the 1941 experimental Paxo Plant and chlorate-drying plant (in Building B – euphemistically referred to as the ‘Bakery’) were recorded. These include two buildings, large metal vats, rolling platforms, an angled platform, ovens, concrete walls, a chimney, and numerous drains and pipes. Other buildings in the fort also contained archaeological material relating to the plants, including graffiti recording grenade numbers on building walls, and the installations of showers in a washroom. These features were part of a project to create phosphorous chloride ammunition for grenades in 1941 that is well-documented in the Military Archives. This related to operations carried out at The Plant in the 1940s in a disused laundry at Parkgate Street (now the Criminal Courts) that has been archaeologically documented by Franc Myles.

Archaeology Plan, 32 Fitzwilliam Place Dublin 2