What improved?
Large wheels and a wide track supported fast passenger travel. Only one pair of wheels was driven.
THE ENGINE ROOM / 11
Small parts. Big discoveries.
A little steam. A clever machine. Let’s see what makes it move.
ON THE WORKBENCH4-2-2 · Broad gauge1847 · 4-2-2 · Broad gauge
Explore the steam history timeline
3D MODEL
Iron DukeThe photograph shows the 1985 replica of the 1847 design. Broad gauge was 7 feet and a quarter inch. Details inside this teaching model are reconstructed.
Drag to turn · Scroll or pinch to zoom · Right-drag or two-finger drag to panTap a part to discover it
Ready when you are
FROM THE HISTORICAL RECORD · 1847 · 4-2-2 · Broad gauge
THE ENGINE’S STORYMeet Iron Duke
Iron Duke ran on the Great Western Railway’s broad-gauge track. Its giant driving wheels helped it cover a long distance with each turn. The rails were much farther apart than those used by most British trains today.
Original, replica or teaching model?
Read the source The photograph shows the 1985 replica of the 1847 design. Broad gauge was 7 feet and a quarter inch. Details inside this teaching model are reconstructed.
How did life change?
Faster trains brought towns closer together. Different track widths caused trouble when people and goods had to change trains.
In the archive
Select a photograph to look closer. Captions distinguish originals, replicas and related examples.
Replica of GWR broad-gauge locomotive Iron Duke.
David Ingham from Bury, Lancashire, England · CC BY-SA 2.0Archive record ↗
YOUR NEXT DISCOVERY
Look closer. Have a go. Find out.Think like an engineer.
Mind the gauge
Help a train fit its track. Compare standard and broad gauge, then match three wheelsets to the right rails.
Job 1: This wheelset needs standard gauge, about 144 cm. Move the rails until their gap matches the wheels.
Gap: 130 cm
No timer. Try as often as you like. These puzzles explain ideas; they are not instructions for operating a real engine.