358 



HYDROGRAPHICAL SURVEYING [chap. xv. 



Object 

 elevated. 



In the second case, we have a spherical triangle with three 

 sides known, as in Fig. 71. 



Here, Fig. 71, we have Z 0, the zenith distance of the object 



Fig-. 71. 



Z S, and O S, as before, the app9t:ent zenith distance of sun 

 and angular distance ; to finrl O Z S, the horizontal angle 



