The world clock.

The 97-photo archive covers all 24 city faces, the underside, column and pavement. The reader preserves the engraved names and minute corrections. Directions use English E for east (the monument uses German O). The ground scale is quadrantal degrees: 0 at north/south, 90 at east/west; it is not minutes.

This remains a photo-led reconstruction, not an exact surveyed replica. The column carries photographed engraving; the compass is reconstructed from the references. Dimensions, orbital geometry, texture joins and drum-to-north alignment remain approximate. Photo textures retain the photographed lighting and wear.

The slider rotates the hour band; it is not a live world-time service. The geometry lab is an experiment, not a K4 solution.