The city shall designate some suitable and permanent point upon the courthouse in the city to calculate and ascertain the exact elevation and distance of the point above the level of the sea and permanently mark on that point by marks which cannot be erased or destroyed its distance and elevation above the level of the sea and record the location and description of the point and its distance and elevation above the level of the sea and the markings thereon in the proper records in the office of the Street Commissioner, which point, when calculated, ascertained and properly marked and recorded, shall be taken as a benchmark for the grades of all streets and alleys within the corporate limits of the city.
(Prior Code, § 23-73)