[CHAPTER XII]
THE MACHINERY OF A SHIP
THE REVERSING ENGINE — MARINE ENGINE SPEED GOVERNORS — THE STEERING ENGINE — BLOWING AND VENTILATING APPARATUS — PUMPS — FEED HEATERS — FEED-WATER FILTERS — DISTILLERS — REFRIGERATORS — THE SEARCH-LIGHT — WIRELESS TELEGRAPHY INSTRUMENTS — SAFETY DEVICES — THE TRANSMISSION OF POWER ON A SHIP
With many travellers by sea the first impulse, after bunks have been visited and baggage has been safely stored away, is to saunter off to the hatches over the engine-room and peer down into the shining machinery which forms the heart of the vessel. Some engine is sure to be at work to remind them of the great power stored down there below, and to give a foretaste of what to expect when the engine-room gong sounds and the man in charge opens the huge throttle controlling some thousands of horse-power.
By craning forward over the edge of the ship, a jet of water may be seen spurting from a hole in the side just above the water-line, denoting either that a pump is emptying the bilge, or that the condensers are being cooled ready for the work before them.
Towards the forecastle a busy little donkey engine is lifting bunches of luggage off the quay by means of a rope passing over a swinging spar attached to the mast, and lowering it into the nether regions where stevedores pack it neatly away.
In a small compartment on the upper deck is some mysterious, and not very important-looking, gear: yet, as it operates the rudder, it claims a place of honour equalling that of the main engines which turn the screw.
To the ordinary passenger the very existence of much other machinery—the reversing engines, the air-pumps, the condensers, the "feed" heaters, the filters, the evaporators and refrigerators, and the ventilators—is most probably unsuspected. The electric light he would, from his experience of things ashore, vaguely connect with an engine "somewhere." But the apparatus referred to either works so unobtrusively or is so sequestered from the public eye that one might travel for weeks without even hearing mention of it.
On a warship the amount of machinery is vastly increased. In fact, every war vessel, from the first-class battleship to the smallest "destroyer," is practically a congeries of machines; accommodation for human beings taking a very secondary place. Big guns must be trained, fed, and cleaned by machinery; and these processes, simple as they sound, need most elaborate devices. The difference in respect of mechanism between the King Edward VII. and Nelson's Victory is as great as that between a motor-car and a farmer's cart. It would not be too much to say that the mechanical knowledge of any period is very adequately gauged from its fighting vessels.