Speed and Power

In the 1930s, British engineer Nigel Gresley introduced a new class of Pacific locomotives, known simply as the A4s. Never has a more mundane name been applied to a more romantic set of locomotives, but most passengers were not interested in letters and numbers.

The very first that went into service in September 1935 had a name to fire the imagination - it was Silver Link and it was a sensation. In essence, this was a development of earlier Gresley Pacifics, though with any number of technical improvements, such as the use of a double blast pipe and a double chimney, all adding together to create a more efficient engine.

For over a hundred years, locomotives had appeared with everything on show, so that the physical reality of a vast boiler providing steam through pipes and gears to cylinders was easily apparent.

Not any more: now everything was encased in a sleek, metallic shell, carefully shaped to reduce air resistance. It looked startlingly modern, yet the idea was not entirely original. Gresley had visited France and seen a sleek new diesel rail car designed by a man better known for cars on the road than for cars on rails, Ettore Bugatti. In fact, Bugatti had taken out his first patent for a rail car as early as 1911, but the design for French railways was sketched out in 1931. It inspired Gresley and the result was to be seen on his new engine. Silver Link was streamlined.