From and after March 15, 1904, no building, except churches, shall be erected or altered in the City of Baltimore on the territory bounded by the south side of Madison Street, the west side of St. Paul Street, the north side of Centre Street, and the east side of Cathedral Street, to exceed in height a point seventy feet above the surface of the street at the base line of the Washington Monument. P.L.L., 1915, §739A 1927, §739A 1930, §739A 1938, §865 1949, §524 1969, §14-1 1904, ch. 42