Methylated Spirit or Wood alcohol is pure alcohol with the addition of 10% Methanol.
It is used in older style commercial model Steam engines as the fuel to fire the water in the Boiler to produce Steam .
It produces a near colourless flame. Which in a brightly lit area can be very hard to see and is essentially invisible, This obviously creates a potential burning hazard, for this reason its use in commercial model Steam has largely been replaced by solid fuel tablets which burn with a visible flame.
Methylated Spirit is usually Denatured to prevent it being drunk.
