The Crimean War changed this perception. French armoured floating batteries successfully engaged Russian forts (the British built similar batteries, but did not bring them into action during the war). Unarmoured British gunboats were also successful against forts. This lesson was repeated during the American Civil War. More powerful guns which appeared after 1865 presented the even more attractive possibility of destroying an enemy fleet by shelling it from just outside the protected port. It now became far more profitable to attack an enemy port than to blockade it. Both the Royal Navy and the French navy built ‘coast defence’ ships which might more properly be described as coast (or port) attackers.12 The French wrote about their ‘seagoing siege train’. To the extent that harbour attack became the favoured tactic in the Royal Navy and in its French counterpart, the fleet in the Channel was no longer the long-range seagoing entity of the past, with its scouts arrayed ahead of it. Because they had vital interests far from the British Isles, the British also needed seagoing armoured ships which would be deployed at long range. However, once they arrived at their destinations, they, quite as much as the shorter-range coastal ships, would be attacking an enemy fleet in port.
A fleet crashing into an enemy port to destroy everything inside had only a limited need for scouts. For example, the fleet which ascended the Turkish straits in 1878 included no cruisers (the sole cruiser in the area, HMS Raleigh, was among the ships which remained at Besika Bay).
HMS Dolphin. Dolphin and her sister Wanderer were the first British sloops to be armed with breech-loading guns. Originally classified as gun-vessels, they were reclassified as sloops while under construction. These photographs were taken when the ship was completed, armed with two 6in and two 5in breech-loaders. The stern view shows closed ports (embrasures) on either side of the ship’s stern, a feature of many British sail-and-steam warships of this period. Guns on slides could be moved between the embrasures and side ports. Embrasures made it possible to fire dead astern (there were similar ports forward) without fouling the trunk into which the ship’s single propeller was hoisted when she was under sail. Sailing qualities were essential to ships which would spend much of their time under sail so as to conserve coal and thus to achieve the long endurance demanded of cruising warships. These ships displaced 925 tons (157ft pp × 32ft × 14ft). Dolphin had a 720 IHP compound engine and was rated at 11.3kts; endurance was 1700nm at 10kts. Both ships were built under contract by Raylton Dixon of Middlesbrough; Dolphin was launched on 9 December 1882. She became a sailing training ship in 1899, when the larger corvettes of the Training Squadron were discarded. In 1907 she was hulked as an accommodation ship for submarines; in 1912 she became a submarine depot ship.
This did not change the need to protect trade and interests abroad. Both the British and the French built second-class battleships (which in the Royal Navy were superseded for a time by armoured cruisers) for individual operations on distant stations. They had both a cruising role and a port defence role; they backed unarmoured cruisers.
The situation began to change as underwater weapons developed. The American Civil War showed that underwater attack, e.g. by mines, could damage or sink large ships in confined waters. It might be difficult or even impossible for the coast defence ships to approach an enemy port to destroy the fleet inside. With all its difficulties, a fleet operating well offshore might be the only viable means of wielding sea power. That in turn demanded creation of a steam equivalent to the earlier sailing battle fleet, capable of fighting in the open sea. The further from a port the fleet had to remain, the more it would need scouts – fleet cruisers.
A fleet forced (by the torpedo and mine threat) to stand well outside the port containing an enemy fleet badly needed scouts. The attacking fleet also wanted to be able to use torpedoes, and cruisers turned out to be better torpedo platforms than battleships: they enabled an admiral to wield his two disparate weapons, gun and torpedo, flexibly. Too, a British fleet waiting for an enemy fleet to come out might well find itself pursuing that fleet. In 1884 the Merseys and their immediate successors were described as adjuncts to the ironclads capable both of scouting and of forcing a faster enemy fleet to action (the French in particular seemed to be building faster capital ships). That justified arming them with heavy guns. As the manoeuvre experience described below shows, the cruiser was soon seen primarily as a scout – and it was wanted in ever-increasing numbers.
The cruiser role changed again beginning in 1896, when DNC Sir William White sold the Admiralty Board the idea that new lightweight armour made it possible to produce a cruiser with battleship protection – in effect, the battlecruiser.
Fleet Operations: The 1884 Analysis
The rising role of cruisers within fleets is evident in an 1884 analysis of the fleet Britain would need in a war against France, at that time the most powerful potentially hostile sea power. It was conducted by Captain W H Hall, head of the Foreign Intelligence Committee.13 Hall’s work seems to have been an attempt to stave off increasingly loud voices arguing that the Royal Navy had fallen behind the French. Hall’s analysis offers a contemporary professional picture of the sort of naval war the Royal Navy expected to fight.
There must still have been advocates of convoy operations: Hall took pains to reject both convoy and other proposed means of trade protection as impossibly expensive (and also as unacceptably defensive). A modern reader might be surprised by how little of the French navy was normally active. Most of it, like most of the British fleet, was in various levels of reserve, awaiting activation by called-up reservists (the idea of nucleus crews was far in the future). Thus the offensive concept was to deal with the active enemy fleet at sea while rushing blockading squadrons to seal the rest in before they could be activated to the point of steaming out. Since reservists came from the merchant fleet, and since the British had a far larger merchant fleet than the French, it was reasonable to imagine that the British could mobilize more quickly. For that matter, mobilization would be a war warning.
Hall advocated mounting an immediate offensive against French forces overseas and already active in the Mediterranean (which might otherwise attack British shipping) while blocking the main French ports (containing the bulk of the [unmobilized] French fleet), destroying French shipbuilding facilities, and also destroying overseas coaling stations and bases.
Aside from ships deployed on foreign stations, the active French fleet consisted of an Evolutionary Squadron based on Toulon and an Eastern Squadron based in the Levant, looking after French interests in Syria. The Evolutionary Squadron consisted of two first-class and four second-class armour-clads, one despatch vessel (to link it to the command ashore), a gun-vessel, and two torpedo boats (it seems unlikely that the latter could go very far to sea; they were presumably to ensure that the squadron could get to sea in the event a hostile fleet appeared). A fifth second-class armour-clad was in 1st Reserve at Toulon, hence could probably get to sea to join the squadron. To deal with this squadron Hall envisaged a British fleet consisting of two first-class and six second-class armour-clads plus two corvettes and six torpedo vessels. The corvettes were presumably the fleet’s scouts, and the expectation probably was that the French would be caught in Toulon. The French Eastern Squadron consisted of a frigate and two corvettes, against which Hall envisaged a British squadron headed by a frigate and three corvettes (first-class rather than second).
Hall did not envisage sending fleets into French harbours. Each of his blockading fleets included both means of defence against the torpedo boats (torpedo vessels, which soon emerged as torpedo gunboats) and scouts (typically a frigate and two corvettes). Hall did not say so, but presumably the frigate would normally watch the port, the corvettes linking her to the armoured squadron further offshore. The exceptions were Cherbourg, for which Hall allocated one first-class and three second-class corvettes; Rochefort, for which he allocated two corvettes. At the time it appeared that the French were building much larger torpedo craft in the form of avisos, capable of operating well offshore on a sustained basis and thus denying