FOR A NEW FORM OF LIGHTHOUSE, ETC. 161 



the edge of the disc, and at equal distances. The vessel 

 here represented cannot float in less than seven fathoms 

 water, though it is possible that with a slight modification 

 of form a lightship could be adapted for certain situations 

 that would rest on the bottom, or float, according to the 

 height of the tide. Where the depth of water will allow 

 of it, the structure would be improved by keeping the 

 centres of gravity and buoyancy further apart than here 

 proposed. This would be best accomplished by enlarging 

 the capacity of the upper part of the dwelling, and placing 

 the ballast still further from the surface of the water. 



The discomfort that would arise from a residence five 

 fathoms below the surface of the water is found when 

 examined, to be at least as little objectionable as that 

 attendant upon any floating dwelling away from land. 

 The inhabitants are safer than in a lightship of the usual 

 construction or in an ordinary vessel, there being slight 

 danger of being capsized, drifted away, or wrecked. They 

 are safe from the fury of the waves, and protected from 

 the violence of the wind. They do not fear that their 

 vessel may be consumed by fire, or injured by strokes of 

 lightning. From the shape and strength of the lightship 

 there is little chance of foundering ; but, should it spring a 

 leak, the spherical weight can be released from within, 

 when the vessel will rise to the surface, but still remain 

 vertical; the hatches can then be made up, a signal 

 hoisted, and assistance waited for. The dwelling, even 

 during storms, is free from motion, and secure from noise ; 

 it is, moreover, protected from the frosts of winter, and the 

 intense heat of summer. Some daylight may be intro- 

 duced down the tube by means of reflectors, but this is of 

 little importance, as the services of the attendant on duty 

 are required on the gallery or in the light-room. No 

 better plan could be devised for securing ample ventila- 

 tion. The danger to be apprehended from being run down 



SER. III. VOL, I. Y 



