Page:The Development of Navies During the Last Half-Century.djvu/289

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Steam Propulsion.
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them a grand working margin as compared with other cruisers," So far The Times, but we do not yet know exactly how these two ships will turn out. Their machinery is, however, our latest and most ambitious effort in the way of naval marine engineering, and forms a remarkable contrast to the engines of fifty years ago.

Perhaps in nothing has the advance of the use of steam on board warships been so extraordinary as in the number of auxiliary engines now considered necessary. And this is a source of danger. The 'Sans Pareil,' for example, has in addition to her main engines no fewer than fifty-eight auxiliary steam engines on board. Some of these are only used occasionally for special purposes, but an enumeration of them will show that many must be constantly in use. They are as follows:—

Main circulating engines, 4
Auxiliary condenser do., 2
Main fire engines, 2
Auxiliary do., 2
Bilge engines, 2
Turning engines, 2
Reversing engines, 2
Distilled water, 2
Drain tank, 1
Evaporator feed, 2
Ventilation supply, 4
Ventilation exhaust, 2
Forced draught, 8
Main feed, 4
Auxiliary feed, 4
Air compressing, 4
Dynamo, 3
Capstan, 1
Hydraulic pumping, 2
Auxiliary do., 1
Friedman's ejectors, 4

When the ship is at sea it is clear that these engines, many of which are constantly at work, and all of which must be ready to work on an emergency, will consume an appreciable proportion of the coal assumed in the