Next, let's develop the full story of microstructural development in this eutectoid steel over a wide temperature range where diffusion is the dominant factor. However, now we're getting into more subtlety as we start to talk about heat treatment and varying these rates. Let's say that we now, back to the black ink. Let's say that we now cool down to about 500 degrees Centigrade, very rapidly. What would happen there upon cooling, we're going to get a somewhat different story. It will be basically the same overall result, but because we're now holding at 500 degrees Centigrade, what we see is we end up now with a fine perlite at the end because that diffusion coefficient is starting to play a role now. It's taking longer for the atoms to re-ring themselves from this single uniform homogeneous phase of the 0.77 percent carbon in solid solution. To this very carbon-depleted alpha iron ferrite and then the carbon-rich cementite compound. So, in this case even though the cross points here are somewhat different here. We're getting a more rapid onset of the product formation, 50% point occurring earlier in the final completion of the formation of the complete microstructure is fine perlite, is created more rapidly. The important point is that the structure becomes finer as we go down to lower temperatures. And then as we go further still, let's say we go down to 300 degrees Centigrade. Round out the diffusional transformation story. Now we'll do a, theoretically, instantaneous crunch down to 300 degrees Centigrade, [COUGH] and then hold, This for an extended period of time. We'll see now that diffusion is really dominating the story. And so it takes us much longer to get the incipient formation of another phase, another phases. Longer still for the 50% point, and then longer still for the completion of the formation. But now what we see, of course, is that we really don't have time to form that very nice lamellar alternating layers of perlite, but the somewhat busier microstructure of bainite, and finer yet dispersion of alpha and Fe3C. The important thing is we go to increasingly fine grained structures.