ON LIGHTHOUSE CHARACTERISTICS. 403 



These lights are all too slow to do full advantage 

 to the triple flash system. When one of them is 

 first seen, it is very apt to be confounded with an 

 ordinary "revolving light" that is, a single-flash 

 flashing light. Even somewhat careful watching 

 at all events if the weather or the distance from the 

 light be such as to leave any room for doubt does 

 not always immediately resolve the doubt. A 

 sixfold quickening of each of these lights would 

 greatly enhance its distinctive quality, and would 

 make it really fulfil the condition pointed out by 

 the Elder Brethren of the Trinity House, as the 

 object to be aimed at in every modern lighthouse, 

 " That he that runs may read." 



The satisfactory distinctions of group-flashing 

 lights are exhausted in the groups of two or three 

 or four flashes ; because, to count five or six, or 

 more, would be embarrassing and liable to mis- 

 take at sea. It has been proposed to obtain 

 further distinction by using groups of longer and 

 shorter flashes, as in Captain Colomb's Flashing 

 Telegraph, now in general use, and very thoroughly 

 appreciated both in the Navy and in the Army ; 



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