--- Makefile.orig	Wed Apr 14 18:50:44 1999
+++ Makefile	Wed Apr 14 18:50:51 1999
@@ -5,7 +5,7 @@
 
 CXXFILES = main.C Frame.C Rotated.C Menu.C FrameWindow.C Desktop.C Hotkeys.C
 
-LIBS = -lfltk
+LIBS = -lfltk -lGL
 
 MANPAGE = 1