OCEANOGRAPHY 19 



the Coast and Geodetic Survey organization all the way from the 

 bottom to the top consists of people who have spent their lives in this 

 one specialty. 



While I am on this particular subject, let me carry this problem one 

 step further. It has been suggested that one could do a lot by having 

 ordinary merchant marine ships make these surveys or in the long 

 run that somehow by compiling the data from merchant marine 

 vessels you could produce adequate charts. 



My own opinion is that our experience shows that this just cannot 

 be done. There are several reasons for this. One of the reasons for 

 it is an interesting fact of geometry. 



Merchant ships always take the Great Circle routes from one port 

 to the other or the shortest distance from one port to the other. They, 

 therefore, make many sounding lines which are parallel to each other 

 on routes which are pretty much great circles between ports, and this 

 leads to a curious type of topography. The contour of the soundings 

 made by the merchant ships leads to topography which we call Great 

 Circle topography. It has nothing to do with what the earth is like. 

 The soundings made by the merchant ships are not very well located, 

 the sounding machines are not in very good shape, and the result is 

 that two soundings a mile or so apart may apparently differ by 600 

 feet or so in depth so that, if you are drawing 100-foot contours, you 

 would draw six contours between those two lines, whei'eas if you sur- 

 veyed a line at right angles, you would find that you were going over 

 a flat plane where the depth difference is not more than a few feet. 



So you get tliese lines which are comparable to great circles and 

 this has nothing to do with what the ocean is actually like. The ocean 

 does not pay attention to any arbitrary lines let alone such arbitrary 

 lines as great circles and distances between ports. 



Mr. Oliver. Having had a couple of months of "boot" training with 

 the U.S. Coast Guard in World War II, Doctor, I have a vague 

 recollection of what you are now discussing. But I appreciate that 

 there is a problem involved. 



Dr. Revelle. It is really very simple. The thing is that any job that 

 is worth doing requires a professional. You cannot do a good job 

 as a kind of a supplement or hobby on the side of what your main 

 mission is. The job of merchant ships is to carry goods from one 

 place to the other just as fast as they can and to turn around and come 

 back just as soon as they can. 



The job of the Navy is to defend the country. The job of the Coast 

 Survey is to make charts and maps. 



All three of these jobs are done very well by the professionals, but 

 when a pro tries to do somebody else's job, he turns out to be an 

 amateur. 



Mr. Oli\ter. I have one other question. Doctor. I do not know 

 whether you would care to comment on it or not, but do you know 

 whether there has been a free interchange of data between the Navy 

 and the Coast and Geodetic Survey insofar as surveying material is 

 concerned ? 



Dr. Ee\'ej:.le. Are you talking about equipment now or actual somid- 

 ings ? 



Mr. Oliver. I mean, has there been an interchange of information 

 and data that have been compiled as a result of surveying? 



