Sponging is another important branch of industry centering here--the entire coast being composed of reefs and keys. The numerous sounds and inlets abound with sponges of an excellent quality, one class of which has won an established reputation in commerce, being known as the "Florida Sheep's wool." The cheaper qualities are the "Yellow-boat," "Glove," and "Grass"--the last two being the kinds used particularly by the American Sponge Company, very extensively, in the manufacture of upholstery. Many tons of these sponges are shipped annually for that purpose. This product of the sea is found growing in water from ten to twenty-five feet deep. It is detached from the bottom, and brought to the surface by means of iron hooks fastened to long poles. When first found they are solid, and resemble a jelly-fish. They are then thrown on the deck of the vessel until they die, when they are beaten, washed and wrung out, leaving, as it were, but the skeleton of the original article--this constitutes the sponge of commerce. The amount realized from the sale of sponges gathered and sold at this place, yearly, exceeds one hundred thousand dollars, which costs nothing but the labor of gathering, cleaning, drying, and packing. The rough life these people lead does not make them appear as though they had been fed on mountain-dew, or nurtured on the wings of love; however, they are kind-hearted creatures to their friends. Key West being the entrance to the Gulf of Mexico, it is well fortified by Fort Taylor, thus using every precautionary measure for its protection. Here stands this fort, with its frowning battlements, upon which are mounted the most formidable artillery used in modern warfare. The construction of this fortress was commenced in 1845, and it now protects an important harbor and naval depot. It is built entirely of brick, with two tiers of casemates, and one in barbette. The most exposed and weaker parts of the walls have been strengthened by making them twelve feet thick--solid masonry--which has prepared it to resist any thing but a continued bombardment. There are now mounted for action one hundred and thirty guns; three three-hundred-pound Parrot, thirty ten-inch Rodman, and two fifteen-inch Rodman guns have been placed in position on the barbette tier, in the form of a trapezoid, with bastions at the four angles. The remaining; guns are of smaller caliber. The defenses have recently been increased by two land-batteries, exterior to the fort, commanding the western and northern approaches. One of these batteries mounts twelve, and the other seventeen, fifteen-inch Rodman guns, with magazine traverses. There are also two towers, with casemated batteries, in which are twelve ten-inch guns, to prevent boats landing. All these works are under the supervision of a most accomplished engineer--Colonel Blount, of the United States Navy.