If reliable triple-expansion engines existed in 1850

What if a reliable 220-psi vertical triple-expansion engine had appeared in 1850?

Faster warships and merchant ships become possible, including a differently arranged Warrior, if the breakthrough includes the necessary metallurgy.

The premise gives the Royal Navy reliable 220-psi boilers and vertical triple-expansion engines in 1850, including the metallurgy needed to build them. A Warrior capable of roughly 20 or 21 knots is envisaged, with a taller, possibly two-deck hull to accommodate the vertical machinery. Brunel could also exploit the breakthrough in Great Eastern, although whether its paddle wheels would remain is left open. These merchant and naval projects could encourage further increases in speed. Britain would keep developing the technology while rivals tried to acquire the same industrial capability.