%%
%% The LaTeX Companion, 3ed
%%
%% Example 8-3-14 on page I-611 in "High-level line commands (originating from epic or eepic)".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See https://www.latex-project.org/lppl.txt for details.
%%

\documentclass{tlc3exa}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{111.0pt}

%StartShownPreambleCommands
\usepackage{xcolor,bxeepic}
%StopShownPreambleCommands

\begin{document}
\begin{picture}(100,80)
 \thicklines
  \spline(30,0)(0,0)(20,40)(40,10)(60,55)(90,70)(95,0)(100,30)
 \color{blue} \thinlines
  \path  (30,0)(0,0)(20,40)(40,10)(60,55)(90,70)(95,0)(100,30)
\end{picture}
\end{document}