LIGHTHOUSE ESTABLISHMENT, THE UNITED STATES. 



437 



whose tenure of office is practically during good 

 behavior, where transfers in location are made 

 when the wishes of the keepers and the wants 

 of the service coincide, and whose physical and 

 mental welfare are carefully looked after, that 

 they may be contented in their responsible and 



>lated situations. 



The bo^rd has had the services of some of 

 the brightest and most active minds in the 

 American navy. The lighthouse service has, 

 like the Coast Survey, come to be regarded as a 

 training-school for young officers and as a field 

 for the best efforts of those higher in rank. 

 The roll of lighthouse inspectors contains the 

 names of the flower of the navy ; hence it is no 

 source of wonder that a tour of lighthouse duty 

 is sought by the more ambitious and studious 

 of our naval officers, and that the service has 

 its choice from among the best of them in times 

 of peace. 



The army has also been well represented in 

 the lighthouse service. On the list of the 

 lighthouse engineers will be found many of the 

 names which have given our military establish- 

 ment reputation if not fame, and such have 

 been their victories in solving the problems of 

 sub-aqueous structures, and in opposing suc- 

 cessful resistance to the violent attacks of the 

 elements under the most discouraging circum- 

 stances, that it is a question whether thosa 

 names connected with the erection of certain 

 lighthouses will not live when history has let 

 die the memory of their brilliant military 

 achievements. 



The civil ssrvice has been well represented 

 on the board itself, in connection with the 

 army and the navy, by such men as Professors 

 Bache, Peirce, Henry, and Morton, who have 

 acted as the scientific advisers of the service, 

 and whose names are identified with the solu- 

 tion of problems in physics which have been 

 worked out under their direction in methods 

 for guiding mariners by light at night, and by 

 sound when light was unavailable. Som3thing 

 of the operations of the Lighthouse Board will 

 be detailed in its proper place. 



The lighthouses on the New England coast 

 were constructsd previous to 1840 in two 

 forms, namely: conical towers of rubble- stone 

 masonry and wooden frame towers erected 

 upon the roofs of the keepers' dwellings. The 

 stone towers were built on the natural rock, 

 from stone split from the adjacent ledges or 

 from pieces collected on the bench, sometimes 

 even from fragments of the cliffs rounded by 

 attrition in the surf. The walls were usually 

 three feet thick at the base, tapering to two 

 feet at the top, and the towers varied in 

 height from twenty to fifty feet. At the top 

 of the tower and within the walling of rubble, 

 a dome of brick was turned, with a square 

 opening near the springing-line on one side, 

 forming a scuttle entrance to the lantern. 

 On this brick dome, a flat roof composed of 

 slabs of stone four inches thick was laid, pro- 

 jecting over the walls of the tower from six to 



twelve inches. The lanterns were attached to 

 the towers by imbedding the lower ends of 

 their iron angle-posts into the masonry of the 

 walls some three or four feet, and the entire 

 construction of the towers was rude in kind. 



The wooden towers erected on the keepers' 

 dwellings were framed into the roof of the 

 house. The angle-posts rested on the attic 

 floor-beams unsupported by studding; conse-* 

 quently the framing of the house-roof was dis- 

 torted by the swaying lateral motion of the 

 tower in storms, and there was necessarily 

 some leakage. 



In 1847 the construction of six difficult light- 

 house structures was devolved by Congress on 

 the topographical engineers of the army. They 

 used the iron pile system, when applicable, and 

 made numerous improvements in the combina- 

 tion of the framework, in making appropriate 

 arrangement of elevated apartments for the 

 keepers, in making disk pile foundations for 

 coral or incrusted bottoms, and in improved de- 

 vices for the foundations. Captain W. H. Swift, 

 of this corps, rebuilt the Black Rock beacon 

 in Long Island Sound, some four and a half 

 miles from Bridgeport, Connecticut. Three 

 successive stone beacons, costing together 

 some $21,000, had, in the course of twelve 

 years, been demolished. Captain Swift, at a 

 cost of but $4,600, erected a pile beacon thirty- 

 four feet above low water, three feet higher 

 than any of its predecessors, which is still 

 standing. An artificial foundation was made 

 by placing six twelve-ton stones partly in an. 

 excavation, and by bedding them in concrete, 

 making a solid platform, and setting into it five 

 wrought-iron periphery piles and one center 

 pile, measuring from three to five and a half 

 inches in diameter. They were sunk through 

 holes drilled to receive them, rose in the form 

 of a conic frustum, and were solidly joined to- 

 gether, and properly capped at the top. 



A pile structure was also erected on Minot's 

 Ledge, in the open sea, near Boston Bay, in 

 1847-'8, by Captain Swift, but it was destroyed 

 by the storm of 1851, and the keepers lost their 

 lives. It was based on the solid rock by drill- 

 ing holes five feet deep, in which one center and 

 eight periphery eight-inch wrought-iron foun- 

 dation piles were wedged, and so placed as to 

 form an octagon twenty-five feet in diameter 

 at the bottom and fourteen feet at the top, 

 which had an elevation of sixty feet. On this 

 was placed the lantern, making the height of 

 the whole edifice about seventy feet. The 

 structure was stiffened by a complex system of 

 diagonal bracing connecting the piles. What- 

 ever may have caused the overthrow of the 

 lighthouse and that is still a mooted question 

 it does not appear to have been owing to 

 any fault of the rock fastenings, as the piles 

 were broken or twisted off, leaving stumps 

 from four to six feet long in their original 

 places. 



Brandywine Shoal, in Delaware Bay, about 

 eight miles from the ocean, was begun in 1848 



