This is a model of the two tunneling machines "Tosca" and "Rosa", which are
currently drilling the new underground line in Cologne. It is exhibited at the
information desk at the Alter Markt, the picture was taken on 27 March
2007. On the left is the shield with the cutting wheel, on the right are the
tail modules. The latter run on the lining, using tilted wheels which are
clearly visible here. The grey pipe is used for the ventilation. The switch at
the plinth of the showcase activates an electric motor which actuates the
cutting wheel. The startup of the new underground line is planned for 2010.
<p>
Digital photo by
<a href="http://www-users.rwth-aachen.de/christoph.schmitz2/index.html">Christoph
Schmitz</a>
(<a href="mailto:christoph.schmitz2@post.rwth-aachen.de">christoph.schmitz2@post.rwth-aachen.de</a>)