MARINE LIGHTING EQUIPMENT OF THE PANAMA CANAL. 113 



DISCUSSION. 



The President: — Gentlemen, we will now take up for discussion the paper on 

 "Marine Lighting Equipment of the Panama Canal," which has been presented by 

 Mr. Pattison. 



Commodore Jacob W. Miller, Vice-President: — I have listened with much 

 interest to the able paper which has been presented by Mr. Pattison, and as I am 

 more or less interested in the lighting of ship channels would like to ask him a 

 few questions, and obtain some information upon two or three points. 



He says on the first page of his paper : — "It is generally conceded by lighthouse 

 authorities that the lighted buoy is the greatest aid to navigation produced during 

 recent years. It is inexpensive both in first cost and maintenance, and produces 

 a highly efficient light of from six to fifteen miles visibility, which will burn without 

 attention and with absolute reliability for long periods, even up to a year or more 

 if desired." 



I would like to take issue with him on the subject of the expense of lighted buoys 

 now in use by the Light-house Department. Acetylene buoys are very expensive, 

 costing from $2,000 to $4,000 each. 



The claim that one of the advantages of the buoys is that they can be seen from 

 six to fifteen miles is a disadvantage in the case of narrow waterways. The lighting 

 of a canal prism should be in the nature of a series of stepping stones, from one light 

 to the next with no overlapping rays of light. Strong, far-reaching illumination 

 blinds and confuses pilots, and renders the navigation of narrow channels dangerous. 

 My opinion is based on some experience on foreign canals and studies in this country. 

 A few low-power lights at close distances, so that a ship can pass from one to the other 

 without being confused with those beyond, are much better than any system of 

 long-distance illumination, and I think this manner of lighting is being used through- 

 the narrow portions of the Panama Canal in the same way as in the Kiel and Man- 

 chester canals wh^re the lights are only 300 feet apart, and that acetylene is only used 

 in the Gatun Lake. 



I trust, if there are any gentlemen here connected with electric lighting plants, 

 that they will give us their experience of lighting narrow channels with low-power 

 lights. 



The President: — Is there any other discussion on this paper? If not, will 

 Mr. Pattison kindly close the discussion? 



Mr. Pattison: — The same system of buoy lighting is used on the Ambrose 

 Channel with the same kind of high candle-power lanterns. As far as the buoys 

 used in the Panama Canal are concerned, the majority of them, as stated in my paper 

 will be used throughout the Gatun Lake, which is quite a large body of water. 



