Abstract: A public works machine is disclosed usable particularly for laying vertical artificial drains, of the type comprising a carrier frame, a tool carrying mobile assembly and means fast with the frame for vertically guiding the mobile assembly, characterized in that said mobile assembly (28) comprises a plurality of penetrating tools (34, 134, 234, 334) in particular for simultaneously laying several drains, and in that said guide means comprise a plurality of guide paths with vertical extension (38, 138, 238, 338). Advantageously, the guide paths are formed by suitably stretched cables.