David also explains some of the innovations it made at the time .
The construction of the first 2 - 8 - 4 locomotive is documented in David Weitzman 's book , Superpower : Making of a steam locomotive .
David Weitzman also explains some of the innovations it made at the time .
The construction of the first 2 - 8 - 4 locomotive is documented in David Weitzman 's book , Superpower : Making of a steam locomotive .