[OS X TeX] another TikZ question

[Art Werschulz]

Hi.

Consider the following:

begin{tikzpicture}[shorten >=1pt,on grid,auto,initial text=]
   \node[state]    (1)                        {1};
   \node[state]    (2)  [right= 0.75 in of 1] {2};
   \node[state]    (3)  [below= 0.75 in of 2] {3};
   \node[state]    (4)  [below= 0.75 in of 1] {4};

   \path[-]
   (1) edge node {} (2)
       edge node {} (3)
       edge node {} (4)
   (2) edge node {} (3)
       edge node {} (4);
   \path[->]
   (3) edge node {} (1)
   (1) edge node {} (4);
\end{tikzpicture}

As expected, this winds up giving an undirected graph, except with  
directed path 3->1->4.

Instead of having a directed path 3->1->4, I would like to have an  
undirected path with a heavier line (or a dotted line, or a dashed  
line).  How would I go about doing this?

Thanks once again.

Art Werschulz
207 Stoughton Avenue, Cranford  NJ 07016-2838
(908) 272-1146