The reason for this great decrease in the consumption of coal lies in the gradual improvement
of our power systems, both with respect to the individual pieces of equipment and in the
system as a whole. Just, how do we go about improving the system shown in the sketch?
Looking at it again, it is obvious that it can be broken down into several divisions. First,
there is the fire under the boiler. This involves not only the fuel itself but also the method of
placing the fuel under the boiler and the arrangement for burning it properly.
So let us extend the diagram to look like this: