On Tue, 8 Aug 2017 10:49:50 +0100, Basil Jet
wrote:

On 2017\08\08 10:40, Ding Bat wrote:
Tunneling today is done with an automated mole having a circular cross section,
so a Paris style semi-circular tunnel for double-track is impracticable.
Where does London have multi-track tunnels?

There are numerous between Kings Cross and Potters Bar. I doubt they are
all cut-and-cover.

No, definitely not, but they weren't drilled using TBMs, either. Given
when they were built, I assume they were cut by hand.