CHAP. XXI.] 



OBTAINING THE SCALE 



515 



Case 2. 



Two Ships present. X and Y. 



X being the Controlling Vessel 

 and not less than 200 feet long. 



Ship Y c<,^=-^^-?rrix1r:^rrr-ir^r^ Ship X 

 At single -t \ I I ' Under weigh 



Scale of Miles 

 T 3 



Fig. VI —Obtaining the Scale provis'orally. 



