116 THE EVOLUTION OF THE LIGHTSHIP. 



The lightship equipped with suitable radio apparatus is an exceedingly valuable signal 

 station if properly operated and used to full advantage. During a fog, characteristic radio 

 signals should be automatically sent from lightships and lighthouses. In cases where it is 

 practicable to do so, the radio signal and fog-whistle could be simultaneously operated, thus 

 enabling a ship within range to determine its distance from the lightship or lighthouse with a 

 fair degree of accuracy by noting the interval of time between the reception of the radio 

 signal and the fog-whistle. 



Signal lights fail in fog, the sound of the whistle is often deflected or reflected, but 

 the radio signal is practically instantaneous no matter how thick the fog or how severe the 

 gale. 



Mr. G. H. Blaker (Communicated) : — Several months ago the writer had a conver- 

 sation with Mr. Cook concerning the installation of direct-connected electrically-driven oil 

 units in lieu of the present steam plant used in lightships. 



The writer has had before him since that time the drawings and plans of a first-class 

 light-vessel similar to the one illustrated in this paper, but has been so very busy upon other 

 matters that it has been practically impossible to do anything else than outline such an in- 

 stallation. 



As the writer understands the matter, it would take as minimum about 300 horse- 

 power to handle one of the lightships. It would appear, therefore, that the ideal installa- 

 tion for the lightship, so far as economy of operation is concerned, would be to install that 

 300 horse-power in two units — either two 1 50-horse-power engines direct-connected to di- 

 rect-current generators, or one 200-horse-power engine and one 100-horse-power engine, these 

 engines to be connected at the switchboard so that they could be operated in parallel. 



The propeller should be driven by a slow-speed reversing motor, which could be con- 

 trolled from the pilot-house, absolutely independent of the engineer, and therefore all that 

 the engineer would have to look out for would be the engines, which would maintain con- 

 stant speed under all conditions. 



As the writer understands the matter there are some days that it is necessary for the 

 propeller to be turned over slowly, in order to keep the drag off the chains, or anchors, 

 which hold the boat, and in that case the 100-horse-power engine could be operated for 24 

 hours, if necessary, at a minimum cost of delivering all of the power that is necessary to 

 propel for that service. If the next twenty-four hours required twice that, the 200-horse- 

 power could be put into service, or, if the full power required, both the 200 and the 100, 

 and the full power delivered to the motor which operates the propeller. The controller in the 

 pilot-house operates in the same way practically as a controller is operated in the ordinary 

 large street car. 



At the same time that the 100-horse-power engine is in operation, such storage batteries 

 as are required for lighting of the service lamps and the lighting of the vessel could be 

 charged, and it might also be found practical and feasible to install a fair-sized storage bat- 

 tery to operate the bilge pumps, the fresh-water pumps, and such light machinery as might 

 be called upon for intermittent service. A motor-driven winch for hoisting the anchor could 

 also be installed without much difficulty, and at the time that the power was not required 

 the whole outfit could be idle for several months during the summer, if necessary, and the 

 power could be available, by having the quick-start oil engine, in from two to three minutes, 

 if it is required. 



