Specifications

Newspaper Article : London Evening Standard Thursday 7th April 1898

Her Majesty's ship Hermes, which is to be launched on the Clyde today, is a second class protected cruiser, being one of the improved Juno class of vessels recently delivered to the Admiralty, two of which - the Venus and Diana - were built by the Fairfield Company.  The Hermes is one of three vessels ordered in December 1896 by the Admiralty, to be built in private yards, two of which were secured by the Fairfield Company.

Her dimensions are :- Length between perpendiculars, 350 ft ; breadth, extreme, 54 ft ; displacement, 5600 tons.  

The hull is built of Siemens - Martin steel throughout to Admiralty requirements on the usual principle adopted in warship construction.  She has a cellular bottom extending the full length of the engine and boiler spaces and before and abaft these watertight flats of the magazines &c., continue the double bottom right to the stem and stern.  Under the protective deck the side compartments for the full length of the boiler space are utilised for stowing coal.  The hull is sub-divided by longitudinal and travers bulkheads into numerous watertight compartments, the number of watertight doors having been reduced to a minimum, and all being worked from the main deck as well as from below.

The stern post, struts and stem are of phosphor bronze.  The vessel has a ram stem, and the structure behind is especially strong, and efficiently connected to the general framework of the vessel, with a view to the contingency of ramming.  The rudder, also of phosphor bronze, is of the balanced type, and controlled by Barfield's compensating gear below the protective deck.

The vessel being intended for foreign service and long cruises at sea, in which the maintenance of a uniform speed becomes essential, she has been completely covered to above the load waterline with teak of a minimum thickness of 3.5 inches and coppered.  To secure steadiness of gun platform, so necessary in a vessel intended for war purposes, bulge keels extending for about half the vessels length amidships have been fitted.

The protection of the vessel consists of a curved deck extending from stem to stern, ranging from 3 in to 1.5 in in thickness, covering the whole of the propelling and steering machinery space, and whilst affording a water line belt of coal protection, they being sub-divided into watertight compartments, give additional security in the event of damage.

An armoured conning tower of Harveyised steel is placed forward, fitted up with the usual means of navigating the vessel and directing operations while in action.  The whole of the connections for which are protected by a steel tube extending to the protective deck.

Bridges are fitted both at the fore and after ends for navigating the vessel under ordinary conditions with the usual compasses, steering wheels, &c.  Three search lights are operated from these bridges, and the vessel throughout is fitted with a complete installation of electric light.

The coal capacity is normally 550 tons but provision ha been made for carrying a greater quantity if necessary.  The magazines and shell rooms are of ample capacity and are conveniently situated for working the quick firing guns, special gear being supplied for manipulating the ammunition.  The ventilating and pumping arrangements of the vessel are on the usual elaborate scale observed in ships of this class.

The accommodation for the officers and crew is of an ample nature, the latest fittings being provided.  The complement of men and officers reaches 500 all told.  

Her armament consists of eleven 6-inch, eight  12 pounder quick firing guns, and a number of smaller machine guns.  The guns are all protected by extra thick shields.  Two submerged torpedo tubes are fitted forward, capable of working the latest pattern torpedoes.  The ship has two masts fitted with military tops for working machine guns, and rigged with fore and aft steadying sails.  A signal yard is fitted on the foremast as well as the new multiple fibre signal lamp at masthead.

The propelling machinery will consist of two sets of triple expansion engines fitted in two sets of rooms.  Each set having four inverted cylinders and four cranks.  The high pressure cylinders 42 in diameter and each of the four low pressure  48 inch in diameter, all adapted for a stroke of 2 ft 6 in.  The cylinders are all separate and independent castings, each fitted with a cast iron barrel or liner and steam jacketed.  Each of the high pressure and intermediate pressure cylinders is fitted with piston valves, and each of the low pressure with flat side valves. all worked by the usual double eccentric and link motion calve gear.  

Th reversing engines are of the all round type, capable of being reversed, with worm and wheel gear.  All the levers being fitted with a slot and adjusting screw to allow of the expansion of steam in the cylinders being altered.  The back colums are of cast iron, fitted with separate guide faces, and the front columns are of forged steel, the engines being arranged with the starting platform amidships.   The condensers are of brass and placed at the wings, the steam being condensed outside the tubes.  There are two centrifugal pumps of gun metal, each worked by an independent engine.  One in each engine room, and arranged with a cross connection so that either or both condensers can be supplied with cooling water from either pump.  The feed, bilge and hotwell engines are all independent and separate from the main engines, steam being supplied by a special range of auxiliary condenser, one being fitted in each engine room, and each condenser is fitted with a circulating pump and small air pump.

Feed water filters are fitted to prevent any impurities reaching the boilers.  The crank, thrust and propeller shafting is of forged steel and hollow.  The crank pins are fitted with centrifugal lubricating apparatus.  The propellers are of gun metal, each propeler having three adjustable blades.  Steam is supplied by 18 Belleville water tube boilers of the latest type, fitted with economisers and adapted for a working pressure of 300 lb.  The boilers are arranged in three boiler rooms and there are three funnels and engines are fitted in the stokeholds to insure the necessary supply of air, also air pumping engines being fitted to deliver air direct into the furnaces and combustion chambers.

The vessel will also be fitted with the usual auxiliary machinery, viz :- A complete distilling plant to supply fresh water to the boilers and also for drinking purposes ; two sets of engines and dynamos for producing the necessary current for electric lighting ; one double cylinder engine with the necessary gear for steering purposes ; two complete sets of air compressing engines and pumps, with the air resevoirs, for charging torpedoes ; and one refrigerating machine of the cold air type, with the necessary cold chamber for ships' provisions.

It is contemplated that the vessel will attain a speed of 20 knots under usual conditions at sea with the power provided.