One of the cultural gems of Bermuda since the year 2000 is the grand Commissioner’s House, built in the 1820s with a commanding view over the old Royal Naval Dockyard and now the headquarters of the National Museum (est. 1975 and 2013).

The House is one of the great icons of the Age of Cast Iron, when, instead of using timber, architects and engineers built in cast and wrought iron, for steel on an industrial scale did not make its appearance until the later 1800s.

As steel is essential today for larger buildings, so iron was in the earlier periods of the nineteenth century, but like steel, its essence was in its prefabricated and replicable nature.

Of course, cast iron was used much earlier than the 1800s, not for buildings, but for the sometime demolition thereof in the form of artillery called cannon.

That type of gun replaced those of wrought iron, made individually by blacksmiths, and ultimately bronze cannon, also fabricated like cast iron guns.

The point of casting was that a single ‘pattern’ was made into which molten iron was poured to produce a gun: the pattern could be reused a number of times and thus the form of the gun could be replicated (prefabricated), giving a consistent production of a particular ‘line’ of artillery.

Cast and wrought iron, and bronze guns ruled the waves and topography for upwards of four centuries, when they were all made obsolete with the invention of ‘gun steel’ in the last quarter of the 1800s.

Steel guns rule all in present times and are not likely to ever be replaced by some other metal form of artillery.

It was that technology of replication that appealed to builders in the late 1700s and they began to produce cast iron columns, particular for warehouses and factories, that would carry timber joists and flooring, without rotting or needing to be of an immense size to do the work needed under compression, which is one of the great structural strengths of cast iron.

While not doing such a good job under tension, architects began to design joists, wall plates and roof trusses of cast iron early in the 1800s.

Of such structures, the Commissioner’s House at Bermuda, the Royal Naval Hospital at Port Royal, Jamaica and the Woolwich Arsenal Smithery (now reconstructed at the Ironbridge George Museum) are outstanding examples of that new building approach. Because of casting, members of a roof truss design, for example, could be replicated as much as necessary, and the whole sent out ‘prefabricated’ to British overseas stations, such as the dockyards at Bermuda and Jamaica.

Thus the cast and wrought iron members for the Commissioner’s House were all sent to Bermuda in the mid-1820s, all numbered and ready to be bolted together to form the structural membrane of the building, excepting the walls, which were of the harder variety of the local limestone, quarried right in the Dockyard.

The designers of that unusual building were Edward Holl, Chief Architect for the Royal Navy and the eminent Scottish engineer, John Rennie (1761—1821).

In the mid-1970s, the English historian of Royal Naval Dockyards, Jonathan Coad, pointed out to the museum trustees the importance of the Commissioner’s House for this period of architectural and engineering history, a message that led to its ultimate restoration in 2000.

As mentioned several weeks ago, the seven cast iron lighthouses designed by Alexander Gordon in this hemisphere, including that here at Gibbs Hill, are part of the extraordinary use of such iron technology, as was the great Floating Dock Bermuda (1869—1901) and the large military barracks at Prospect and St George’s Camps of the Royal Artillery and regiments of the British Army.

Given the evidence of a watercolour by Johnson Savage MD of about 1835 (recently donated to the National Museum, along with 38 other images of Bermuda in 1833—36), we can now with certainty add the once magnificent Royal Naval Hospital (erected 1818) on Ireland Island South to the inventory of cast and wrought iron buildings, designed by Holl and Rennie, even though the structure was sadly demolished in 1972, after an ignoble use for several decades as a battery to produce chicken eggs.

In the Savage image, the building is two-storied like the Commissioner’s House and as with the latter, it had verandas on both levels, the whole supported by cast iron columns.

These supported cast iron wall plates, to which in turn were bolted cast iron facias ‘boards’, and ultimately connected with a network of cast iron girders to carry the Yorkstone floor of the two levels of the veranda, and at the uppermost level joined with the ends of the roof trusses.

Without the Savage image and lately acquired photographs, much of the iron ‘timberwork’ was earlier thought to be composed of wood.

Most of the Royal Naval lands northeast of Watford Bridge were acquired by the Bermuda Government after the Second World War and the descendants of the original families that were evicted from the 200-odd acres in 1809 had no opportunity to buy back their ancestral properties.

Along with those lands, the government of the day also acquired all of the other military and fortification sites throughout Bermuda, from Daniel’s Head to St David’s Head, including the south shore beaches, once also private property.

It is perhaps fair to say that until the establishment in 1975 of the Bermuda Maritime Museum (now the National Museum), few in authority appreciated the value of the Dockyard and the other military sites to Bermuda and to the vital tourism trade.

That was partly in line with the lack of interest elsewhere in dockyards and artillery fortifications, a situation now being changed for the better.

However, in the decades from the War and into the 1970s, only Fort St Catherine, Gate’s Fort, Fort Hamilton and Scaur Hill Fort received much restoration and conservation attention from the central authorities.

Dozens of military structures and feature were lost through neglect or misuse, most being potential assets to the economy of Cultural Tourism.

The grand cousin of the Commissioner’s House, the Royal Naval Hospital went from sickbed to scrapheap in the early 1970s and its rubble and ironwork went into the sea to replace the ‘Piano Bridge’ between Watford and Boaz Islands.

Dodging some modern bits of flying metal, you can see for yourself the cast iron members and stone from the building that are eroded out of the south side of the road created in place of the bridge, a secret of past cultural heritage exposed by recent hurricanes and winter storms.

Edward Cecil Harris, MBE, JP, PHD, FSA is Director of the National Museum. Comments may be made to director@nmb.bm or 704-5480.