“Undreamed-of sciences from year to year Upon dim shores of unexplored Night Their steady beacons kindle.” He now bent his energies to bring before Congress the condition and needs of our lighthouse system. He wrote a vigorous and detailed letter exposing the abuses and the schemes of the ignorant set of plunderers who were opposing improvement. He proved that often important lighthouses were left for days in charge of wholly incompetent persons. Hence there was waste, robbery, and inefficiency, while a powerful combination held the system in its coils. “The Lighthouse Ring” was then as strong as that of “The Indian Ring” of later years. Further, the battle was one of science and new ideas against ignorance and ultra-conservative old fogyism. The lenses were struggling against the reflectors. The latter were the outcome of the emission theory of the propagation of light. The Lenticular method was based on the undulatory theory. Ignorance and avarice long held the field, but under the hammer-like facts and arguments of Perry, and those who thought with him, both were routed, and the present grand system is the final result. Our lighthouse establishment is not a creation, it is a growth. At the Centennial Exposition at Philadelphia in 1876, the exhibit made by the government of the United States was under the charge of Rear-Admiral Thornton A. Jenkins, one of Perry’s pupils and friends. The triumphs of a half century in the illuminating art were manifest. Progress had at first crept by slow steps, from rude beacons of wood or coal fires on headlands, to oil lamps with flat wicks and spherical reflectors, to paraboloid mirrors and argand burners, to eclipse revolving or flashing lights. The katoptric system of Teulère, based on the reflection of light by metallic surfaces was introduced about 1790, and soon came in vogue among most civilized nations. It was costly and expensive, since half the rays of light were lost by absorption in the mirror even when new and perfectly polished; while the loss was far more when the mirror was old, unclean, or in constant use. Yet despite its many defects, it was the best of its kind known until Fresnel’s brilliant discoveries based on the principle of a burning-glass or convex lens refraction. After a struggle, the dioptric conquered the katoptric, and lenses rule the coast. It was to introduce the dioptric system that Perry now earnestly labored. The influence of his arguments in Congress was powerful, and from this time the lenticular method prevailed, and the system of lighthouses on all our coasts was extended. From the first lighthouse built by the general government in 1791 at Cape Henry, the number had increased to seven in 1800. In 1838 there were but sixteen. The number now is not far from 250.