CHAPTER VI 



Roughest 

 Form of 

 Survey. 



Modified 

 Running 

 Survey. 



Graduat- 

 ing Be- 

 forehand. 



Method of 

 Ordinary 

 Running 

 Survey. 



RUNNING SURVEY 



A RUNNING survey, the least accurate form of " sketch " 

 survey, is one where the best part of the work is done from 

 the ship running along the coast, fixing points, sketching in 

 the coast-line and prominent parts of the land, and sounding, 

 at the same time. 



It is capable of many modifications, more especially with 

 regard to the fixing of the main points. 



The rudest form of running survey is where, beginning upon 

 nothing, everything is eventually put on paper by observations, 

 angles, and soundings taken from the ship without anchoring. 



At the other extreme comes a running survey made upon 

 some main points already fixed by triangulation of some kind, 

 and which has for its object only the sketching of coast-line 

 and detail of an inaccessible coast, which is assisted by occa- 

 sional anchoring, and where sounding would be carried on in 

 the boats as well as the ship, after enough natural objects have 

 been fixed by the angles from ship stations. 



In making an extensive running survey of the simplest kind 

 — i.e., where we commence on nothing, and only run past the 

 coast once — it is well to have the paper graduated (see p. 386), 

 ns astronomical observations from time to time will fix the 

 scale of the^ chart, and it is easier to plot these positions when 

 the sheet is graduated. 



The course and the distance run by the ship between each 

 position where series of angles are taken, as given by patent 

 logs, will form a series of bases, which will have to be, how- 

 ever, modified afterwards to agree with the positions astro- 

 nomically fixed, which must be taken as the fundamental 

 points of the chart. 



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