During the past twenty years the changes in the “matériel” of which fleets are composed have been so rapid and universal that it has been impossible at any time to form a true estimate of the strength of the navy of any maritime power that would be of any value beyond a very limited time. With displacements advancing from 5000 to 13,000 tons; weight and power of ordnance developing beyond the most exaggerated conceptions of twenty years ago; torpedo warfare springing into existence and developing as a new and special arm; modifications in engines and boilers by which speed has been developed from 12 to 18 knots, and steaming capacity from 2500 to 6000 miles; the revolution of naval tactics, and the entire change in the conditions of naval warfare brought about by the development of armor defence and the ram attack,—it is only through paying the closest attention and under exceptionally favorable circumstances that naval officers have been able to comprehend the magnitude of the general result.
It is only within the past two years that the craze for naval development has subsided to a slow and steady advance, and the present time has been seized upon as one favorable for measuring the actual strength and resources of the navies of the world.
In preparing this work the author has simply aimed at representing in as detailed a manner as possible all the elements which go to make up the active naval strength, leaving to those who in their search for information may have recourse to the data herein presented to estimate the values of these elements as they are developed and combined in different navies, and to judge for themselves of the true value of the results obtained.
In collecting this data the greatest care has been taken to only give such as is entirely authentic. For the most part it has come from official sources, and, wherever it has been necessary to make comparisons or to give opinions, the writer has in no case given his own independent ideas on the subject. The principal authorities, aside from official records, whose works have been consulted are: Reed, White, Dislere, Marchal, and De St. Bon, on Naval Architecture; Owens, Mayevski, Sebert, Müller, and Cooke, on Ordnance; Schleeman and Stotherd, on Torpedoes; and Von Billerbeck, on the iron-clads of the first decade.
Washington, June, 1880.