In its original guise as a sailing ship, the cruiser (sometimes rendered cruizer) was a fourth-rate ship or large frigate that was generally detached from the main fleet to sail independently in search of the enemy, whose position was then reported back to the fleet so that a major engagement could be brought about. The term cruiser was also employed for frigates and smaller vessels operating independently against the enemy’s maritime lines of communication in what is generally known as the ‘guerre de course’ role. In both these tasks, the essential requirement of a successful cruiser was its ability to sail better than any prospective enemy, especially in terms of speed and ability to point high into the wind. All this changed with the advent during the middle part of the 19th century of steam propulsion, and of iron (later steel) construction and protection. At this time cruiser ceased to be a generic name for any warship acting independently of the main fleet and became a type of warship in its own right. The pure cruiser came into existence during the middle and later parts of the 19th century in four basic types, namely the armoured cruiser with a displacement of up to 14,600 tons and a high level of protection matched by an armament of powerful guns, and the protected cruiser that was built in three subclasses with horizontal deck armour but no vertical belt armour, as well as the supplementary protection and survivability offered by the arrangement of the coal bunkers on the sides of the ship along the waterline and the compartmentalisation of the hull’s interior spaces. In descending order of size, these three subclasses were the first-, second- and third-class protected cruisers with maximum displacements of 14,200, 6,000 and 3,000 tons respectively.
The British built a total of 136 cruisers of these ‘pre-Dreadnought’ types in the form of 35 examples of the armoured cruiser and 21, 51 and 29 examples respectively of the first-, second- and third-class protected cruisers. The armoured cruisers were intended to provide a scouting capability within sight of the Royal Navy fleets to which they were attached, and also to serve as the flagships of overseas squadrons in areas that did not need the combined political and naval power represented by a battleship, while the tasks of the three subclasses of protected cruiser were the protection of British merchant shipping as it plied the seas of the world, the escort of convoys of troopship on their way to and from various parts of the British empire, and the provision of a ‘naval outpost’ capability in less advanced parts of the world. By the outbreak of World War I in August 1914, 51 of these older ships had been deleted or reduced to non-combatant status, and another seven had been converted into minelayers. It is also worth noting that the Royal Navy also possessed 10 small cruisers with a displacement of up to 1,850 tons.
The evolution of the cruiser through the second half of the 19th century paralleled that of the battleship. The type started as a wooden vessel: to this core were first added both a layer of protective armour and steam machinery to supplement the three-masted ship rig with its full complement of sails; then came a progression of interim stages in which iron and then steel became the primary structural medium and the steam propulsion system gradually superseded the sailing rig; and finally the cruiser reached the point at which the masts survived only in vestigial form to provide the means of hoisting flags and carrying control tops, and the main armament comprised a mixed assortment of breech-loading weapons in which the largest-calibre guns were carried in trainable turrets, the intermediate-calibre guns were installed in casemates, and the smallest-calibre weapons were carried on open mountings with perhaps a shield as the only protection for the gun’s crew. The three main weapons carried by British cruisers were the 9.2-in (234-mm) gun firing a 380-lb (172-kg) shell, the 7.5-in (191-mm) gun firing a 200-lb (91-kg) shell, and the 6-in (152-mm) gun firing a 100-lb (45-kg) shell.
Typical of the British cruiser types before the advent of the ‘Dreadnought’ era in 1906 were the first-class cruisers of the ‘Warrior’ armoured and ‘Diadem’ protected classes, the ‘Challenger’ second-class cruisers, and the ‘Pelorus’ third-class cruisers. The ‘Warrior’ class, of which four were launched in 1905, had a full-load displacement of 13,550 tons, an armament of six 9.2-in (234-mm) guns, four 7.5-in (191-mm) and 23 3-pdr quick-firing guns, armour protection up to a maximum thickness of 6 in (152 mm), and a speed of 23 kt on the 23,000 hp (17150 kW) provided to two shafts by triple-expansion steam engines. The ‘Diadem’ class, of which eight were launched between 1896 and 1898, had a full-load displacement of 11,000 tons, an armament of 16 6-in (152-mm), 14 12-pdr and three 3-pdr quick-firing guns, armour protection up to a maximum thickness of 4.5 in (114 mm), and a speed of 20.25 kt on the 16,500 hp (12300 kW) provided to two shafts by triple-expansion steam engines. The ‘Challenger’ class, of which five were launched in two subclasses between 1898 and 1902, had a full-load displacement of 5,880 tons, an armament of 11 6-in (152-mm), nine 12-pdr and six 3-pdr quick-firing guns, armour protection up to a maximum thickness of 3 in (76 mm), and a speed of 21 kt on the 12,500 hp (9320 kW) provided to two shafts by triple-expansion steam engines. The ‘Pelorus’ class, of which 11 were launched between 1896 and 1900, had a full-load displacement of 2,135 tons, an armament of eight 4-in (102-mm) and eight 3-pdr quick-firing guns, armour protection up to a maximum thickness of 3 in (76 mm) on very limited areas, and a speed of 20 kt on the 7,000 hp (5220 kW) provided to two shafts by triple-expansion steam engines.
These ships were rendered obsolete by the development of the ‘Dreadnought’ type of capital ship and comparable evolution in the warships of smaller types, but were still in extensive service on the outbreak of World War I. The armoured cruisers were generally retained for service in home waters until their losses up to and including the Battle of Jutland in May 1916 revealed their terrible weakness against the longer-ranged and considerably heavier shells of more powerfully armed opponents. The protected cruisers, on the other hand, had already served a useful function, and continued to do so, in their activities in overseas waters in the pursuit and destruction of Germany’s merchant raiding force. The ships of this type were also very useful later in World War I, when they were used for the convoy escort role in the North Atlantic. A major turning point in the design of cruisers came in 1904/05 with the advent of the ‘River’ class of light warships, in which the torpedo boat and torpedo boat destroyer finally came of age as a single type offering a genuine ocean-going rather than merely coastal or at best sea-going capability. The new ocean-going destroyer was a far greater threat to major surface forces than the earlier coastal or even sea-going torpedo boat, and the commanders of major surface forces now had to take into consideration the possibility of massed attacks by torpedo-firing ships using their speed and agility to evade destruction and thus close to torpedo range. The growing threat posed by the destroyer in the early part of the 20th century therefore called for the development of a new type of light cruiser that was light and fast enough to work with destroyer flotillas, for which it provided a command capability, and also fast enough and sufficiently well armed with quick-firing guns to operate in the defensive screen that provided the squadrons of larger warships with a first line of defence against attacks by the enemy’s destroyer flotillas.
The first results of this new requirement were the 15 ships of the ‘Scout’ type that were built between 1904 and 1912 with a displacement in the order of 2,700 to 3,500 tons, and the 21 ships of the ‘Town’ type that were built between 1909 and 1915 with a displacement in the order of 4,800 to 5,500 tons with a much greater endurance and the ability to operate semi-independently from remote bases. There were in fact six classes of ‘Scout’ type light cruisers, of which the last was the three-strong ‘Active’ class with a displacement of 3,440 tons, an armament of 10 4-in (102-mm) guns and two 21-in (533-mm) torpedo tubes, no protection, and a propulsion arrangement of steam turbines delivering 18,000 hp (13420 kW) to two shafts for a maximum speed of 26 kt. There were five classes of the ‘Town’ type light cruisers, of which the last was the two-strong ‘Birkenhead‘ class with a displacement of 5,200 tons, an armament of 10 5.5-in (140-mm) guns and two 21-in (533-mm) torpedo tubes, protection in the form of a 3-in (76-mm) belt, and a propulsion arrangement of steam turbines delivering 31,000 hp (23115 kW) to four shafts for a speed of 26.5 kt.
Early experience with the ‘Scout’ and ‘Town’ types of light cruiser indicated that they were useful types of warships, but that a hybrid type would be best suited to the requirements of working with major surface forces in the North Sea, which was the area in which the Grand Fleet intended to secure a climactic victory over the German High Seas Fleet in the event of an outbreak of war between the UK and Germany. This hybrid type combined features of the ‘Scout’ and ‘Town’ types with a more potent propulsion arrangement for the higher speed required for effective use in conjunction with the Grand Fleet and its fast destroyer flotillas. The first of the new classes, which eventually totalled nine including the five ships of the ‘Delhi’ class completed after the end of World War I, was the ‘Arethusa’ class of eight ships that entered service just before the outbreak of the war. As built, the ships had a displacement of 3,512 tons, an armament of two 6-in (152-mm) and six 4-in (102-mm) guns as well as eight 21-in (533-mm) torpedo tubes, protection in the form of a 3-in (76-mm) belt and 1-in (25-mm) deck, and a speed of 30 kt on the 40,000 hp (29825 kW) provided to four shafts by four sets of steam turbines. Wartime changes included a revision of the gun armament to three 6-in (152-mm) and four 4-in (102-mm) guns as well as one 4-in (102-mm) or two 3-in (76-mm) anti-aircraft guns, the latter reflecting the first stage of the aeroplane’s developing impact on naval operations; at the same time the original pole foremast was replaced by a tripod foremast. The ships were somewhat cramped but soon proved themselves very well suited to their task, and were therefore used as the basis for steadily improved successor classes whose main changes were a larger number of 6-in (152-mm) guns in replacement of 4-in (102-mm) weapons. The details of the ‘Delhi’ class included a displacement of 4,650 tons, an armament of six 6-in (152-mm) guns and two 3-in (76-mm) anti-aircraft guns as well as 12 21-in (533-mm) torpedo tubes, protection in the form of a 3-in (76-mm) belt and 1-in (25-mm) deck, and a speed of 29 kt on the 40,000 hp (29825 kW) provided to four shafts by four sets of steam turbines.
As the leading maritime power in the world during the last years of the 19th century, the UK was generally followed rather than led in the basic shape of naval developments, although rivals such as Germany sought to offset British numerical superiority with qualitative superiority in matters such as firepower and speed. At the beginning of World War I, the German navy had six armoured cruisers, of which the most advanced were the two ships of the ‘Scharnhorst’ class with a displacement of 11,600 tons, an armament of eight 8.2-in (210-mm), six 5.9-in (150-mm) and 20 3.4-in (88-mm) guns as well as four 17.7-in (450-mm) torpedo tubes, protection in the form of a 6-in (152-mm) belt and 2-in (51-mm) deck, and a speed of 22.5 kt on the 26,000 hp (19385 kW) provided to three shafts by triple-expansion steam engines. Germany, it should be noted, also produced just one example of a what may be regarded as a heavy armoured cruiser. This was Blücher designed to provide a capability comparable to that of the ‘Invincible’ class, which were the Royal Navy’s first battle-cruisers and originally described for disinformation purposes as being armed with 9.2-in (234-mm) guns. The Germans therefore responded to their first perception of the ‘Invincible’ class ships with a design based on that of the ‘Westfalen’ class of ‘Dreadnought’ battleships but scaled down and fitted with a primary armament of 8.2-in (210-mm) guns. This resulted in a vessel characterised by a displacement of 15,500 tons, an armament of 12 8.2-in (210-mm), eight 5.9-in (150-mm) and 16 3.4-in (88-mm) guns as well as four 17.7-in (450-mm) torpedo tubes, protection in the form of a 6.75-in (170-mm) belt and turrets, and a speed of 26 kt on the 44,000 hp (32805 kW) provided to three shafts by triple-expansion steam engines. Inevitably Blücher was too lightly armed and armoured to be a real battle-cruiser, and paid the penalty at the Battle of the Dogger Bank in 1915, when she fought alongside the German battle-cruisers and was completely overwhelmed.
The German navy also operated 17 protected cruisers approximating in overall capabilities to the British second-class protected cruisers, and of these it was the 10 ships of the closely related ‘Gazelle’, ‘Nymphe’ and ‘Frauenlob’ classes that were the most modern, all having been completed between 1899 and 1903 with a displacement of between 2,645 and 2,715 tons, a primary armament of 10 4.1-in (105-mm) guns and two 17.7-in (450-mm) torpedo tubes, protection in the form of a 2-in (50-mm) deck, and a speed of 21.5 kt on the 8,500 hp (6340 kW) delivered to two shafts by triple-expansion steam engines.
In the first part of the 20th century Germany decided, like the UK, that the protected cruiser was conceptually obsolete and that the immediate future lay with the light cruiser. Germany therefore undertook a major design and production effort, resulting in the construction of no fewer than 14 light cruiser classes in the period up to the end of World War I. The first of these, completed in 1904, was the ‘Bremen’ class of five ships typified by a displacement of 3,250 tons, an armament of 10 4.1-in (105-mm) guns and two 17.7-in (450-mm) torpedo tubes, protection in the form of a 2-in (50-mm) deck, and a speed of 23 kt on the 11,000 hp (8200 kW) delivered to two shafts by triple-expansion steam engines. The last, completed in 1918 and therefore reflecting the very considerable changes that had taken place in light cruiser thinking as a result of operations in World War I, was the second ‘Dresden’ class of two ships typified by a displacement of 6,150 tons, an armament of eight 5.9-in (150-mm) guns, two or three 3.4-in (88-mm) anti-aircraft guns, and four 19.7-in (500-mm) torpedo tubes, protection in the form of a 2.5-in (65-mm) belt and a 0.75-in (20-mm) deck, and a speed of 28.5 kt on the 45,000 hp (33550 kW) delivered to two shafts by steam turbines. The remarkable thing about these two classes, and this was also evident in comparable British classes, was their conceptual similarity: the ships of the later class were larger, were armed and protected more heavily, and possessed a higher speed as a result of a more powerful propulsion arrangement based on steam turbines rather than triple-expansion engines, but in overall terms the design of the ships was just that of the earlier class’s units on a larger scale and incorporating improvements suggested by more extensive operational experience.
To be continued…