Despite starting second, Cecilia will run slightly faster, aided by geological data fed back from Florence, meaning that both machines are due to break through at around the same time.
HS2 has launched Cecilia - the second 2,000t tunnelling machines that will excavate the 10 mile long tunnels beneath the Chiltern hills just outside London. The first machine, Florence, was launched just over a month ago.
Despite starting second, Cecilia will run slightly faster, aided by geological data fed back from Florence, meaning that both machines are due to break through at around the same time.