2-8-8-0 "Consolidation Mallet" Locomotives in the USA
The AT&SF (Santa Fe) was the first to experiment with this wheel arrangement.
They seemed to enjoy the creation of new locomotives by rebuilding smaller
engines into bigger ones. They took two 2-8-0s (Consolidations) and rebuilt
them into a 2-8-8-0 configuration. As a result, this wheel arrangement
is sometimes called a "Consolidation Mallet". On the Great Northern these
were sometimes called the "Bull Moose" type.
Railroads that used 2-8-8-0 "Consolidation Mallet" Locomotives in the USA (data provided by Steve Llanso of Sweat House Media)