The Tsar Cannon, which you probably saw in the Moscow Kremlin or in photographs, is not the only weapon of its kind. In Great Britain in 1854, the designer Robert Mallett proposed to create a monstrous mortar. While Mallett was struggling with the English bureaucracy, the Crimean War, in which the mortar's debut was to take place, came to an end. Despite this, the project was completed, but the result did not make the military happy. But many tourists today are grateful to Mallet for the wonderful scenery for Instagram. Both mortars built have survived to this day, and they are still very photogenic.
How Robert Mallett came to the idea of creating a 914-mm mortar
An engineer from Great Britain of Irish origin Robert Mallett turned to the idea of creating a super-powerful mortar back in the 1850s. The impetus to work in this area was given by the Crimean War of 1853-1856, in Great Britain it is better known as the Eastern War, while in Russia it went down in history under the name of the Crimean War, since the main hostilities really took place in the Crimea. The British needed a new powerful mortar to cope with the fortifications and forts of Sevastopol, which they could not take. It was the fight against fortifications that was the main task of the most powerful mortar in history.
By the time the Eastern War began, Great Britain had siege mortars, but the most powerful of them had a caliber of 13 inches (330 mm), which is already a lot, but the military wanted a miracle weapon. Sensing where the wind was blowing, Mallet stepped up his work on creating a super-powerful mortar, presenting the first draft of the future gun in October 1854. It should be noted here that Mallett came to the development of the mortar for a reason, wanting to make money on the military department. For this he had all the necessary skills and knowledge.
Back in the 30-40s of the XIX century, Robert Mallet conducted numerous studies of the propagation of seismic waves from explosions in the ground. It was these studies of his that led the engineer to the idea of creating a huge mortar. In the future, Mallett wanted to achieve the same local effect in the explosion of a projectile, which would be comparable to an earthquake. The specialist believed that such an approach is promising also for the reason that the very need to accurately hit the target will disappear. A direct hit is actually a rather rare luck, so he wanted to compensate for possible misses with the force of seismic vibrations, which would be enough to damage or completely destroy the fortification. At the same time, today many researchers believe that it was Robert Mallett who was one of the first engineers to seriously study the seismic effects of explosions.
In the middle of the 19th century, a similar effect could be achieved only by combining two factors: the fall of the projectile from a very high height and giving it as much mass as possible. The combination of these factors could provide a large penetration of the artillery shell into the ground, followed by an explosion. This could be achieved by significantly increasing the caliber of the artillery mount and giving a large elevation angle of the gun. This is how the idea was born to create a mortar with a barrel diameter of approximately 914 mm or 36 inches. At the same time, creating such a weapon, the developer inevitably faced the problem of large weight, which also had to be somehow solved.
Difficulties in building a mortar Mallet
The first mortar project was completely ready by October 1854. The proposed option could not be called technological. Mallett suggested placing a 36-inch mortar without a standard base directly against the platform. The platform, which was supposed to serve as a carriage, the designer proposed to build from three rows of roughly hewn logs laid crosswise. This design was supposed to give the barrel an elevation angle of 45 degrees. The entire structure was planned to be placed on a site specially prepared and strengthened during earthworks. During the design process, the mortar changed for the better. For example, Mallet was pointed out to consider the possibility of sea-based. Gradually, the designer expanded the capabilities of the miracle weapon by providing the ability to move, using means to change the angle of inclination of the gun, using large charges and increasing the volume of the chamber.
The first official presentation of the project of a new mortar was carried out by Robert Mallet on January 8, 1855. The prepared drawings, along with accompanying notes, were submitted by the engineer for consideration to the Committee for the technical re-equipment of artillery. Mallett did not receive the expected reaction. The committee reasonably doubted the prospects of such a mortar and was not ready for unconventional and untested projects, preferring more earthly models of artillery weapons. However, the inventor did not give up and decided to directly appeal to the most dignitaries of the empire. Mallett did not waste time on trifles and already at the end of March 1855 wrote a letter to the Prime Minister of Great Britain personally. At that time, the post was held by Lord Palmerston.
Palmerston not only got acquainted with the letter he received, but also admired the very idea that the engineer was describing. Later, he personally met with the designer and finally fired up the proposed idea. With such a patron, it seemed that things should have gone faster. However, the Committee for the technical rearmament of artillery continued to show its conservatism, deciding to fully use all possible bureaucratic delays in order to slow down the consideration of the project and the placement of an order for the release of mortars. As further events will show, in many respects the workers of the committee were right and simply did not want to let government money down the drain. However, neither the prime minister nor the designer was going to give up. Mallet secured a personal audience with the Prince Consort by making a trip to Windsor. A member of the royal family also decided that the project was worth trying to put it into practice. In turn, Palmerston put pressure on the lieutenant general of artillery, directly appealing on May 1, 1855 to Hugh Dalrymple Ross, the future British field marshal.
It is important to understand here that the failures of the British army in the Crimea, most likely, played a role in promoting the 914-mm mortar project. The assault on Sevastopol, which the troops of Great Britain, France and Turkey planned to complete within one week, turned into a 349-day saga. This was the merit of the city's garrison, the sailors of the Black Sea Fleet, the population of Sevastopol, as well as skillful commanders: Kornilov, Nakhimov and Totleben. At the same time, the main merit of Count Eduard Ivanovich Totleben was that this talented military engineer in a short time managed to build serious fortifications near the city, which the Allied armies stormed for 11 months. At the same time, the city and its defenders survived six large-scale bombings.
Under pressure from senior members of the government, the army and the royal family, the Artillery Committee surrendered and began work, organizing a tender for the construction of the Mallet mortar. On May 7, 1855, it was won by the Blackwell company Thames Iron Works, which was ready to fulfill the order to build two mortars in 10 weeks. The announced price was approximately £ 4,300 per gun. Here the story repeated itself, which is familiar to many from the modern Russian system of public procurement. Most likely, the tender was won by the company that requested the lowest price. However, already in the course of the work, it became clear that the company did not have all the necessary competencies and capabilities, the work was delayed, and the company itself went bankrupt in the process of work and began bankruptcy proceedings. As a result, the order was transferred to three other British firms.
The work was completed only 96 weeks after the receipt of the contract. Mortars were delivered in May 1857. By this time, not only the siege of Sevastopol was over, Russian troops left the city on August 28, 1855, but the Crimean War itself, the peace treaty was signed on March 18, 1856. Thus, Mallet's mortars were late for the war, during which they could be used for their intended purpose.
The design of a 914-mm mortar
The project, developed by engineer Robert Mallett in the middle of the 19th century, provided for the creation of a mortar typical for that time, that is, a short-barreled gun, the barrel length was only 3.67 caliber. The gun was originally developed for firing at enemy fortified positions and fortifications along a steep hinged trajectory. The main feature of the project was a huge gun caliber for that time. At the same time, the Mallet project had a number of important interesting decisions. For example, Robert Mallett originally planned to make a mortar from several separate sections that could be assembled on site. This solution simplified the process of delivering and transporting a huge heavy weapon on the battlefield, especially in off-road conditions. The engineer also provided for a hoop barrel assembly system. According to his idea, such a design was supposed to increase the strength of a huge caliber weapon due to shrinkage.
The barrel of a 914-mm Mallet mortar consisted of a large number of parts, the weight of each of which made it possible to organize transportation in any way available at that time without significant difficulties. One of the features was that the charging chamber in the Mallet mortar was significantly narrower than the main bore. The designer chose such a solution on the basis that a small amount of powder charge would be enough to throw ammunition at a distance of the intended firing, which was rather small for mortars of those years.
Structurally, the mortar consisted of a cast base, the total weight of this cast iron part was 7.5 tons. On the base, a trunnion, a flange and all the necessary devices were placed to set the required angle of inclination of the barrel. The mortar chamber was forged and made of wrought iron, the total weight of the element was 7 tons. The muzzle of the mortar consisted of three large compound rings made of wrought iron. In this case, the three rings themselves were assembled from 21, 19 and 11 prefabricated rings. They were all held together with hoops, the largest of which was 67 inches in diameter. In addition, the structure was strengthened by six longitudinal rods of almost square cross-section, made of wrought iron. They combined the barrel ring and the molded base of the mortar. When assembled, the 36-inch Mallet mortar weighed approximately 42 tons, with the heaviest part weighing no more than 12 tons.
Mallet's mortar, like the vast majority of the heavy artillery of Great Britain and other countries of the world at that time, was muzzle-loading. Bombs weighing from 1067 to 1334 kg were fed to the muzzle of a huge gun using a winch. The bombs themselves were spherical and were hollow inside. In this case, the cavity itself was made eccentric so that the bomb would not tumble in the air when it left the barrel.
Mallet mortar trials
Both mortars did not have time for the Sevastopol siege and, in fact, were not needed by the military, but they still decided to test the miracle weapon. One mortar was allocated for firing tests. In total, the British military managed to fire only 19 rounds. At the same time, the tests took place in 4 stages: October 19 and December 18, 1857 and July 21 and 28, 1858. The tests were organized at the Plumstead Marshes test site.
At the end of the tests of the 914-mm Mallet mortar, the military used ammunition weighing 1088 kg. The maximum firing range, which was achieved in polygon conditions, was 2759 yards (2523 meters). When flying at such a distance, the ammunition was in the air for 23 seconds. The maximum rate of fire that was achieved during the tests was approximately four rounds per hour. As a result of the tests carried out, the military came to the conclusion that mortars have no prospects for real combat use.
The decision is quite reasonable, considering that each time the shooting was interrupted by breakdowns and subsequent repair of the mortar. During the first firing, only 7 shots were fired, after which a crack formed on one of the outer rings of the barrel. The second time the tests were stopped after 6 shots, this time the reason was the rupture of the central hoop tightening the lower ring. In the future, malfunctions continued to arise, although for the third shooting, the military switched to lighter ammunition weighing 2400 pounds (1088 kg), with which the best firing range result was achieved. Despite the fact that the mortar remained maintainable, the military decided to abandon further tests, spending a total of 14 thousand pounds on the project.
In fairness, it is worth noting that a number of historians believe that the main reason for the frequent breakdowns of the mortar during the tests was not the unsuccessful design proposed by the engineer, but the poor quality of the metal used and the low level of production culture. It was not possible to improve the properties and quality of the metal used in the manufacture of the barrel in the mid-19th century and the current level of development of metallurgy, science and technology.
