# Approximation of any reversible process by carnot cycle

While studying thermodynamics i came across the fact that any reversible cycle can be represented by series of miniature carnot cycles. I am unable to understand how can it be done for every cycle as carnot cycle has 4 reversible processes that may or may not be part of the reversible process that we want to represent. And i also unable to understand how geometrically can it be fitted to any reversible process. Please help in this.

Figure 7.1 answers the question but the $$PV$$ graph makes it hard to understand the answer. It easier to represent the process on the $$TS$$ graph because the Carnot cycle on this graph is rectangle.
Using tiny rectangles we can reproduce the area of any closed line on the $$TS$$ graph. All tiles move in the same direction (here clockwise), so wherever two tiles share a side they cancel each other out. The net circulation is on the edge and it can be made to match any arbitrary cycle.
The $$PV$$ graph works the same way but the tiles are not rectangles but rather these toothy slices.