The cannon from the Alderney Elizabethan wreck represent a high point in artillery science that would not be surpassed until the Victorian period.
As we have established, the guns from the Alderney ship were of new design, new materials, new carriages and better propellants, and, it seems safe to assume, were arranged to comprise a homogeous, coordinated weapon system.
The large-bore artillery of the Mary Rose was all of bronze; the guns from the Alderney ship were all of cast iron. Clearly, during the period between these two vessels, the domestic ordnance industry had gone through a major technological transformation. This is not to say that brass guns were redundant, but the Alderney wreck does mark the end of a period of transition between bronze and iron, after which the latter becomes increasingly common. To understand the full significance of the Alderney guns, we need to ask why iron, and why then?
It is often thought that bronze (or what the Tudors called brass) was inferior to iron as a material for heavy artillery. This is not necessarily so. Although marginally less durable, bronze was non-corrosive (an important property in a salt-water environment) and it was lighter than iron (a major consideration at sea where weight distribution was a matter of critical concern). On the other hand, bronze tends to absorb and retain heat while iron is more heat resistant, and what it absorbs it dispels quickly. This meant that in an artillery duel bronze guns could, and frequently did, overheat from repetitive firing. Bronze guns recovered by the writer from a ship that went down in a fierce, close-quarter fire-fight, were found to have either lost their muzzles completely or, in one case, to have suffered droop along the chase where the barrel was both thinner and unsupported. Despite the tendency of bronze to overheat, it remained the favourite material of gun crews because it was much safer; whereas an iron gun would explode without warning, a bronze gun, being more elastic, would ‘craze before it bulged, and bulge before it burst’. But in the end, and at a time when England was desperate for more guns, iron possessed one advantage which eclipsed all others, and that was its abundance and moderate cost.
The English ordnance industry was established by Henry VIII when he set up the Royal Ordnance works at Houndsditch in 1511. By the end of his reign (1547) the nation was producing bronze guns that, as the finds from the Mary Rose attest, were as good as any coming out of the best continental foundries. By then the problem faced by England’s domestic ordnance industry was no longer one of technical know-how or workmanship, but rather a lack of gunmetal. Some copper (necessary for making bronze) came from the Mines Royal, but most of the nation’s needs had to be imported at great expense from Hungary. This explains why, in the Queen’s dealings with Drake, she insisted that any ‘brass gonnes’ he might seize were automatically crown property. Treasure might be divided, but never the guns. This stipulation extended even to unserviceable cannon, for an advantage of bronze is that it can be recast, and because of this captured guns were never valued or accounted by their dimensions or shot size, but almost always by weight. Thus it was that Drake captured 116 tons of guns in one of his Indies ventures, and 62 tons on his Cadiz expedition. But these opportunistic acquisitions were not nearly enough to support and sustain a nation at war. To satisfy the demand for guns the Queen was forced to look to the Wealdon ironworks for her heavy ordnance. England might be poor in copper, but it was rich in iron ore.
Naturally the transformation from bronze to iron did not occur overnight. Bronze gun production continued into the Restoration, and of course the existing arsenal continued in service for many years; for instance, bronze guns cast shortly after the Armada were still in service in 1734, and one piece in particular, cast by the famous Elizabethan gunfounder Henry Pitt in 1590 (just two years before the Alderney ship) was still in naval service in 1716 and was not condemned until 1760 or soon after.
Obviously the first generation of cast iron guns were, to some extent, experimental, as it would have taken a little time to perfect the manufacturing process and for designers and gunners to explore the potential and build confidence in the new metal; but all this notwithstanding, the modifications that were made after the Alderney guns were (when one compares the latter with iron guns of two hundred years later) remarkably minor. The new iron guns might not have been as aesthetically pleasing as bronze pieces (whose ornamentation often made them as much works of art as weapons of destruction) but, by the end of the Great Queen’s reign, England was able to produce a surplus of guns in iron that, as functional tools of war, could not be bettered, and with a price-tag that made them highly sought after by nations that had trouble meeting their own artillery requirements. On a Dutch East Indiaman of 1606 excavated by the writer, he and his colleagues were interested to find that along with the standard bronze Dutch guns, there was also a number of iron culverins each emblazoned with the Tudor Rose and the monogram of Elizabeth I.
So when did the change to iron occur? Interestingly, though not surprisingly, it took place during the Armada and post-Armada period when the threat of invasion by Spain was at its sharpest and when the need for guns had never been greater or more urgent (s.v. Historical Background). The earliest document on the state of naval armament was that prepared in 1546 (just a year before Henry VIII’s death) by Anthony Anthony, the Navy’s Surveyor of Ordnance. From the so-called Anthony Rolls we learn that the Navy had 256 guns all of bronze. A typical ship of the Armada period was the Tiger of 1586. It was armed, or intended to be armed, with 4 culverins, 8 demi culverins, 8 sakers, 2 falcons, 2 fowlers and 6 bases – all of bronze. But in two separate surveys conducted in 1595 (just three years after the Alderney ship) we find the Tiger armed with six demi culverins, 14 sakers and two falcons – all of iron. A survey of naval-fire power in 1585 recorded 545 big guns of which only two were of iron, but in a survey of 1595 (just three years after the Alderney ship) we find that the weapon-pile had grown by 71 per cent to 931 guns, and that 137 of the increase were of cast iron. Clearly a major shift in technology, product and supply had occurred within the foundries. The armament industry had gone through its first industrial revolution, and it all happened in less than ten years, the period which also saw the arming and sinking of the Alderney ship.
Forgetting for the moment that the life of a gun is measured in discharges rather than years, it is safe to say that the Alderney guns were new, or virtually new at the time of their loss. Very likely they reflect the earliest English pattern for cast-iron muzzle-loaders, a type of gun that would remain in service for over three hundred years and which, at Trafalgar in 1805, would put an end to Napoleon’s dreams of European conquest. Technically speaking, they would not be surpassed until the Armstrong rifled, breech-loader of 1859.