H O R 



TABLE I. Of the dip of the horizon. 



If the land is not sufficiently distant to afford a free horizon, it may be 

 sometimes necessary to obtain an altitude referred to the surface of the 

 gea at some known or estimated distance. Under such circumstances, 

 the dip may be taken from the following- Table. 



TABLE II. The dip at different distances from the Observer. 



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