The enlisted force of the Navy on the 15th day of August, when it reached its maximum, numbered 24,123 men and apprentices.  One hundred and three vessels were added to the Navy by purchase, 1 was presented to the Government, 1 leased, and the 4 vessels of the International Navigation Company—­the St. Paul, St. Louis, New York, and Paris—­were chartered.  In addition to these the revenue cutters and lighthouse tenders were turned over to the Navy Department and became temporarily a part of the auxiliary Navy.

The maximum effective fighting force of the Navy during the war, separated into classes, was as follows: 

Four battle ships of the first class, 1 battle ship of the second class, 2 armored cruisers, 6 coast-defense monitors, 1 armored ram, 12 protected cruisers, 3 unprotected cruisers, 18 gunboats, 1 dynamite cruiser, 11 torpedo boats; vessels of the old Navy, including monitors, 14.  Auxiliary Navy:  11 auxiliary cruisers, 28 converted yachts, 27 converted tugs, 19 converted colliers, 15 revenue cutters, 4 light-house tenders, and 19 miscellaneous vessels.

Much alarm was felt along our entire Atlantic seaboard lest some attack might be made by the enemy.  Every precaution was taken to prevent possible injury to our great cities lying along the coast.  Temporary garrisons were provided, drawn from the State militia; infantry and light batteries were drawn from the volunteer force.  About 12,000 troops were thus employed.  The coast signal service was established for observing the approach of an enemy’s ships to the coast of the United States, and the Life-Saving and Light-House services cooperated, which enabled the Navy Department to have all portions of the Atlantic coast, from Maine to Texas, under observation.

The auxiliary Navy was created under the authority of Congress and was officered and manned by the Naval Militia of the several States.  This organization patrolled the coast and performed the duty of a second line of defense.  Under the direction of the Chief of Engineers submarine mines were placed at the most exposed points.  Before the outbreak of the war permanent mining casemates and cable galleries had been constructed at nearly all important harbors.  Most of the torpedo material was not to be found in the market, and had to be specially manufactured.  Under date of April 19 district officers were directed to take all preliminary measures short of the actual attaching of the loaded mines to the cables, and on April 22 telegraphic orders were issued to place the loaded mines in position.

The aggregate number of mines placed was 1,535, at the principal harbors from Maine to California.  Preparations were also made for the planting of mines at certain other harbors, but owing to the early destruction of the Spanish fleet these mines were not placed.