The picture clearly shows the astonishing layout of the first generation of 15-inch monitors. The conning tower just forward of the great gun turret must have given the officer of the watch a very poor view of what was going on. The navigator was located in the lower “bird’s nest” on the tripod mast. His compass faithfully followed the alignment of the guns when they traversed, making his job extremely difficult. Soult had two Vickers four stroke 750 horsepower diesels, which proved economical and reliable but were totally insufficient for a ship of her size and bulk. She could barely manage 6 knots. The windage of her upper-works and her underpowered engines made her extremely difficult to steer, causing many minor bumps when going into harbour and often resulting in the ship spinning round without warning when steaming in a strong wind. She was, however a very useful bombardment ship and did some excellent work on the Belgian coast. Her 15-inch turret was reliable and some of her firing was commendably accurate.
After the Battle of the Falkland Islands (7 December 1914) the Admiralty decided that very high speed was an essential requirement for battle cruisers, and so the two new ships being built at that time, Renown and Repulse, were redesigned leaving out two of their 15-inch turrets to reduce weight and increase speed to 32 knots. Eight turrets, four for each ship, however had already been ordered and so two of them from each ship, became redundant. Fisher immediately snapped these up for two new especially powerful monitors. (In the event they were not the actual guns fitted, changing priorities in the Grand Fleet meant that it was more convenient to fit the almost identical 15-inch turrets intended for Royal Sovereign class battleships to the monitors and use those from the battle cruisers elsewhere). The 15-inch Mark 1 gun had been developed by the Elswick Ordinance Company of Newcastle for the Queen Elizabeth class fast battleships. It was an excellent weapon which gave good service through two world wars. Indeed the last British battleship ever built, Vanguard which entered service in 1946, was fitted with a slightly modified version of this same turret. The two new 15-inch monitors were named Marshal Ney and Marshal Soult after the celebrated Napoleonic generals. This time the names, chosen to honour Britain’s Allies, were a source of delight, French officers visiting Ney exclaimed cried out, enraptured “Ah, le plus brave des braves.”
Once again the rush to build these two new ships meant that they were designed before the first 14-inch monitors had been tested and their weaknesses uncovered. To make matters even worse the Admiralty actually found two sets of diesel engines with which to power them. Before the war two fleet oilers had been ordered and it had been decided to fit them each with two 750 horsepower diesels to test the technology. These engines Fisher snaffeled for his two 15-inch monitors. One pair of engines, fitted to Marshal Ney were six-cylinder two strokes designed by a German company, MAN. They were actually assembled by Samuel White of Cowes. The other pair, fitted to Marshal Soult, were eight-cylinder four strokes designed and built by Vickers. Once again the hull design followed the unsatisfactory lines of the first monitors and the ships were pitifully underpowered, making only about 6 knots flat out in still water. The engines did deliver much better fuel economy than steam engines fitted to previous monitors (about 0.6 tons/hour). Diesels, however, brought with them a new set of problems which did not occur with steam engines, reliability. From the start the Vickers engines worked quite well, but the MAN’s fitted to Ney were a nightmare. They stopped for no apparent reason whenever load or speed was changed. They refused to run astern when required to do so. (Like most marine diesels they had no reversing gears, the engine was stopped and re-started backwards). Once stopped, they would be impossible to re-start, the supply of air bottles used to crank the engines becoming rapidly exhausted. On one occasion a fleet bombarding the Belgian coast witnessed the extraordinary sight of this 6,900 ton monitor being towed out of the action with her two 750 horsepower engines both broken down, by the 900 ton destroyer Viking going slow ahead with her 15,000 horsepower steam turbines. While thus being towed she made a good 10 knots – almost twice her normal full speed. Soult’s engines worked well, but unfortunately her propellers were the wrong size for the 150 RPM of the engines. This made her even slower than Ney, but at least she was reliable. The correct propellers were eventually fitted and increased her speed by a little less than half a knot, to about 6.6 knots in still water.
Once again speed of construction was impressive. The ships were ordered in January 1915 and the first, Ney, launched in August. When launched the new ships displaced 6,900 tons and cost £270,000 each excluding the turrets.
The “Marshals” as these ungainly ships were called had other shortcomings. The very high turret was too close to the compass platform, so the compass needle would invariably swing round, following the gun. The steering was appalling, the steering engines being too small and the rudders insufficient, probably the windage of the turret on top of its 20-foot-high column was partly responsible for the bad handling characteristics. Ships berthed near them in harbour mostly showed the scars resulting from their clumsy manoeuvres. In strong winds the ships could not be controlled at all, skidding sideways and sometimes making a complete circle, regardless of the rudder. In practice they needed a tow for any long voyage.
Soult was in action from her launch date for the duration of the war, but underwent some extensive modification. The conning tower was removed and a bridge built aft of the funnel. The funnel itself was lengthened and the mast modified to take two huge searchlights and a revised navigator’s station. The main armament was modified to give 30 degrees of elevation in place of the original 20, thus increasing the range from 26,000 yards to about 32,000 yards (18.2 miles). At the same time extra defensive armament in the form of eight 4-inch guns and anti-aircraft armament was added. The result was to make an already ugly ship certainly the most ill-looking vessel in the navy. She remained slow and ungainly but was a good gun platform, and rendered, as we shall see, some useful service. She was still afloat in 1939 and consideration was given to bringing her back into service, but the plan was abandoned. Ney was so clumsy and unreliable that her main armament was removed and she was relegated to guard ship duties for which she was given a complement of 6-inch guns.
The next batch of large monitors was to be an altogether different proposition. By mid-1915 it was obvious that the performance of all the fourteen large ships already ordered was going to be well short of requirements especially as regards speed and handling at sea. In May 1915 four new monitors with 15-inch guns were provisionally ordered, only to be cancelled when it became clear that guns and turrets could not be supplied without an unacceptable delay in the completion of the Royal Oak class of battleships. It then became apparent that the Marshalls (Ney and Soult) were going to perform even worse than their predecessors, and it was determined that entirely new hulls should be designed, giving a much slimmer more easily driven form, with the screws able to operate efficiently, unobstructed by the bulges in the hull. These new monitors would be equipped with much more powerful engines and the turrets of the disgraced Marshals would be mounted on them. So began the story of Erebus and Terror, which were both to prove very formidable warships.
To achieve better hydrodynamic shape the hulls were lengthened and the anti-torpedo bulges made slimmer. This was achieved by replacing the inner chamber of the bulge, which on previous ships had been open to the sea, by a narrower space filled with sealed steel tubes, the crushing of which would absorb much of the energy of any explosion. Unlike the earlier monitors in which the bulges had been awash, the new ships had theirs projecting 15-inches above the waterline. This made them even more stable and greatly eased the handling of the ship’s boats. The resulting hulls were 405 feet long by 88 foot 2 inches broad as against 355 feet 8 inches and 90 foot 3 inches for the Marshals. Critically the stern sections were much finer giving far better water flow to the propellers. There was a single large rudder. A secondary bow rudder for manoeuvring and for going astern was proposed but not fitted, this bow rudder was proposed at the suggestion of the Dover Patrol, whose experience in bombarding the Belgian coast suggested that it would be useful to be able to deploy the full weight of the ship’s firepower while backing away from the enemy coast. Most important of all, the inadequate engines of previous monitors were replaced by two four-cylinder triple expansion oil-fired steam engines of 3,000 horsepower each, four times the power of the Marshal’s diesels. Armament was similar to their predecessors, with two 15-inch, two 6 inch and two 12-pounder guns plus the usual complement of anti-aircraft weapons. The turrets themselves were not in the end taken from Soult as she was proving too useful to take out of service, so Terror used Ney’s 15-inch main armament whilst Erebus received a brand new reserve turret originally allocated to the battle cruiser Furious. (Furious was designed to have 18-inch guns but a back-up set of 15-inch had been built in case the 18-inch weapons proved unsatisfactory. She was eventually completed as an aircraft carrier with no heavy armament at all). Both sets of guns were modified before fitting to the monitors to have a maximum elevation of 30 degrees which gave them an extra 6,000 yards range (bringing it up to 32,000 yards or 18.2 miles). Armour protection was similar to that in the previous ships. There was a proper bridge in place of the inadequate conning tower arrangement and a tall funnel aft of it, so the ships at last looked like proper warships. The extra machinery weight meant that draft was increased by a little over 1 foot to 11 foot 8 inches.
Astonishingly 1918 did not see the end of British monitor building. Churchill, who was First Lord of the Admiralty in 1939 immediately tried to re-activate the monitor fleet, with the idea of repeating the harassment of German armies moving along the Belgian coast, using the same tactic that was deployed in 1914-18. Erebus and Terror were still in service, although they needed improved deck armour and anti-aircraft armament before they could be risked in combat close to enemy coasts. They were therefore not available until after the blitzkrieg had swept away the French and Belgian armies but, as we shall see, played an important role in other theatres. Soult was still afloat but in such a condition that she would be uneconomic to bring into active service. Her gun turret however was still in good order. The decision was taken to use this and another redundant 15-inch turret in two new monitors, Roberts and Abercrombie. They were supposed to follow the same general design and layout as Erebus and Terror but with enhanced deck armour, a modern radar fit and formidable anti-aircraft capability.