On Main Street and all streets and avenues running parallel therewith the numbering, whether going north or south, shall begin at First Street with “100” on the west side of such street or avenue and with “101” on the east side thereof and at the next street parallel with First Street the numbering shall begin with “200” on the west side and “201” on the east side of such streets or avenues, and so on increasing one hundred with each street or avenue parallel to First Street and with the even numbers and fractions thereof on the west side and the odd numbers and fractions thereof on the east side until all are properly numbered. (Prior code § 5-42).