Height coordinates Two major techniques Measurement of vertical angles (atmospheric refraction) Leveling measurement of height differences over short distances(<50 meters) Level lines were used to transfer height information from one location to another 02/11/02 12.540Lec0202/11/02 12.540 Lec 02 10 Height coordinates • Two major techniques: – Measurement of vertical angles (atmospheric refraction) – “Leveling” measurement of height differences over short distances (<50 meters). – Level lines were used to transfer height information from one location to another