Rising high into the sky, cranes are the tallest machines on a construction site. They lift and move equipment from one part of the site to another. This book explains how these tall machines help build bridges, skyscrapers, and other structures.A Bellwether Media production.
Duration: 3 minutes (00:02:38) Publishing date: 2006-08-01; Unabridged; Copyright Year: 2007. Copyright Statment: —