`"' special: Literal PostScript
-------------------------------
For simple graphics, or just for experimentation, literal PostScript
code can be included. Simply use a `\special' beginning with a double
quote character `"'; there is no matching closing `"'.
For instance, the following (simple) graphic:
[ picture of a grey triangle ]
was created by typing:
\vbox to 100bp{\vss % a bp is the same as a PostScript unit
\special{" newpath 0 0 moveto 100 100 lineto 394 0 lineto
closepath gsave 0.8 setgray fill grestore stroke}}
You are responsible for leaving space for such literal graphics, as
with the `\vbox' above.