We define the \h{Harmonic Fan}
$F_{H}=\cup \{ve : e \in H\}$, where $ve$ is the
segment joining $v=(0,1)$ with
$e\in H$, $H=\{0\}\cup\{1/n:n\in N\}$.
We consider $F_{H}$ as a subset of the
Euclidean plane with the induced topology.
See \cite[p.9]{ccm1990}.