you mix a boiler + tool
steam+steam engine=pressure
Steel+steam engine
cart + combustion engine = car steam engine + gasoline = combustion engine boiler + coal = steam engine
tool + wood= wheel, wheel + wood = cart, cart + combustion engine= car if you don't have combustion engine it's boiler+coal= steam engine, steam engine + gasoline = combustion engine.
acid + metal
boiler + coal
steam and air.
Steam+water
Metal + Steam = Boiler
Air + Steam
air + steam
Steam+water