Most of the big guns are in the navy--on the huge dreadnoughts and battleships--and therefore the fortifications at Helgoland, which are designed to resist the bombardment of the heaviest naval guns, must be regarded as equipment. Helgoland is the protecting fort of Germany's most vulnerable point. It is the Gibraltar of Germany, and protects the entrance to the Kiel Canal from the North Sea. If the British could get past the fortifications to the Kiel Canal, it could establish a close-in blockade which would render Germany helpless in a short time. Helgoland is an island fortress in the North Sea, in the center of which is a mortar battery mounting 11-inch and 16-inch guns, capable of puncturing the decks of the battleship which comes within range; and these batteries have a range of from six to eight miles. The batteries are ranged in tiers, one above the other, to a height of almost 180 feet above the sea level, the heavy guns and pieces being placed below and the lighter ordnance in the upper tiers. The guns range from 17.7-inch caliber down to 8.2-inch. Germany calls Helgoland the "fortress impregnable," and the developments of the war seem to indicate that the description fits. SMALL GUNS OF VARIED INTERESTS. In the smaller guns used in warfare there are many varieties of interest. The United States prior to and with their entrance into war, particularly during the period of the trouble along the Mexican border, experimented with almost every known make of rapid fire machine and field gun, and there was for a time much criticism because the government did not adopt for army use the Lewis gun, which was adopted by some of the foreign countries. The German army rifle carried by all the infantry is of the Mauser type, first introduced in 1888 and gradually improved until 1898. The weapon, because of the adoption of the improved model in 1898, has come to be known as the "ninety-eight gun." It is a quick-firing weapon, from which 20 to 30 shots a minute may be projected by the soldier. The gun is universally used and has a caliber of 7.9 millimeters, which provides for the use of the smallest bullet which will work sufficient injury on the enemy to make its use profitable. Experience in the Russian-Japanese war proved to the military authorities that the use of a smaller caliber was not advisable. It was found that the smaller bullet could, and in many cases did, pass through a man's body without actually rendering him useless, and that in a large percentage of cases--more than one-third--the wounded were back with their troops within a few months.