Our boiler, or steam generator as it is called these days, has now become quite complex
so before we do anything more to it let's hook it up to the rest of the system. As already
mentioned a turbine is essentially a windmill, not a simple fan like the one shown but a more
complex one with many hundreds of blades, some stationary, and some rotating. These
blades are arranged in groups or stages, so that the steam is compelled to pass successively
through the various stages. Here is a very simple diagram.