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. The Signal Corps was promptly organized, and performed service of the most difficult and important character. Its operations during the war covered the electrical connection of all coast fortifications, the establishment of telephonic and telegraphic facilities for the camps at Manila, Santiago, and in Puerto Rico. There were constructed 300 miles of line at ten great camps, thus facilitating military movements from those points in a manner heretofore unknown in military administration. Field telegraph lines were established and maintained under the enemy's fire at Manila, and later the Manila-Hongkong cable was reopened. In Puerto Rico cable communications were opened over a discontinued route, and on land the headquarters of the commanding officer was kept in telegraphic or telephonic communication with the division commanders on four different lines of operations. There was placed in Cuban waters a completely outfitted cable ship, with war cables and cable gear, suitable both for the destruction of communications belonging to the enemy and the establishment of our own. Two ocean cables were destroyed under the enemy's batteries at Santiago. The day previous to the landing of General Shafter's corps, at Caimanera, within 20 miles of the landing place, cable communications were established and a cable station opened giving direct communication with the Government at Washington. This service was invaluable to the Executive in directing the operations of the Army and Navy. With a total force of over 1,300, the loss was by disease in camp and field, officers and men included, only 5.