Hasse Diagram/Examples/British Monarchs

Example of Hasse Diagram
Let $M$ be the set of all British monarchs.

Let $\RR$ be the relation defined on $M$ as:
 * $\forall x, y \in M: x \mathrel \RR y$ $x$ was monarch before or at the same time as $y$



This Hasse diagram illustrates the restriction of $\RR$ to all $x$ of $M$ such that $\text {Victoria} \mathrel \RR x$ and $x \mathrel \RR \text {Elizabeth II}$.