Tunnel-boring machines are genuine marvels of modern technology — self-contained contraptions big enough to build entire subway tunnels, a job that used to require thousands of pick-axes and the sacrifice of quite a few lives. But once construction is finished, getting the machines out can take months.
via Gizmodo http://ift.tt/1AfEqKM http://ift.tt/1zW7nH2
No comments:
Post a Comment