Thank you to Bruce Hirsh for posting this image on Facebook. Adler the developer built homes in the area west of W. 12th Avenue from W. 68th Street down to the equivalent of W. 59th Street. Lovell Brothers built homes west of W. 12th Avenue from W. 53rd Street up to the equivalent of W. 59th Street. Since there was no street at W. 59th Street that resulted in half the block from W. 58th Street north being built at different completion schedules by Lovell Brothers and half the street from 5900 north to W. 60th Street being built by Adler. They even had different house numbering systems for addresses on the same blocks.