diff --git a/tutorial/tutorial.html b/tutorial/tutorial.html
index f23b8dd98a17310609d2f1e6649a6557fa842933..8ae54971005927577d59c50dc3ee9a5d52b46ba3 100644
--- a/tutorial/tutorial.html
+++ b/tutorial/tutorial.html
@@ -23,7 +23,7 @@
 <H1>README 1/10</H1>
 [<A HREF="#top">top</A>][prev][<A HREF="#file2">next</A>]
 <PRE>
-$Id: tutorial.html,v 1.21 2001-08-31 07:08:47 geuzaine Exp $
+$Id: tutorial.html,v 1.22 2001-09-01 09:19:43 geuzaine Exp $
 
 Here are the examples in the Gmsh tutorial. These examples are
 commented (both C and C++-style comments can be used in Gmsh input
@@ -250,8 +250,8 @@ Physical Surface(100) = {6} ;
  *
  *  Gmsh tutorial 2
  * 
- *  Includes, Geometrical transformations, Elementary entities
- *  (Volumes), Physical entities (Volumes)
+ *  Includes, Geometrical transformations, Extruded geometries,
+ *  Elementary entities (Volumes), Physical entities (Volumes)
  *
  *********************************************************************/</FONT></I>
 
@@ -464,7 +464,7 @@ Lc2 = 0.003 ;
 </FONT></I><I><FONT COLOR="#B22222">// Grouping is done, as usual, with parentheses.
 </FONT></I><I><FONT COLOR="#B22222">//
 </FONT></I><I><FONT COLOR="#B22222">// In addition to these operators, all C mathematical functions can
-</FONT></I><I><FONT COLOR="#B22222">// also be used (note the first capital letter):
+</FONT></I><I><FONT COLOR="#B22222">// also be used (note the first capital letter), i.e.
 </FONT></I><I><FONT COLOR="#B22222">// 
 </FONT></I><I><FONT COLOR="#B22222">//   Exp(x)
 </FONT></I><I><FONT COLOR="#B22222">//   Log(x)
@@ -484,11 +484,11 @@ Lc2 = 0.003 ;
 </FONT></I><I><FONT COLOR="#B22222">//   Floor(x)
 </FONT></I><I><FONT COLOR="#B22222">//   Ceil(x)
 </FONT></I><I><FONT COLOR="#B22222">//   Fmod(x,y)
-</FONT></I><I><FONT COLOR="#B22222">//   Hypot(x,y)
-</FONT></I>
-<I><FONT COLOR="#B22222">// An additional function 'Rand(x)' generates a random number in [0,x]
+</FONT></I><I><FONT COLOR="#B22222">// 
+</FONT></I><I><FONT COLOR="#B22222">// as well as a series of other functions:
 </FONT></I><I><FONT COLOR="#B22222">//
-</FONT></I><I><FONT COLOR="#B22222">//   Rand(x)
+</FONT></I><I><FONT COLOR="#B22222">//   Hypot(x,y)   computes Sqrt(x^2+y^2)
+</FONT></I><I><FONT COLOR="#B22222">//   Rand(x)      generates a random number in [0,x]
 </FONT></I><I><FONT COLOR="#B22222">//
 </FONT></I><I><FONT COLOR="#B22222">// The only predefined constant in Gmsh is Pi.
 </FONT></I>
@@ -583,8 +583,9 @@ lcar3 = .075;
 
 <I><FONT COLOR="#B22222">// In order to change these lengths globally (without changing the
 </FONT></I><I><FONT COLOR="#B22222">// file), a global scaling factor for all characteristic lengths can
-</FONT></I><I><FONT COLOR="#B22222">// be specified on the command line with the option '-clscale'. For
-</FONT></I><I><FONT COLOR="#B22222">// example, with:
+</FONT></I><I><FONT COLOR="#B22222">// be specified on the command line with the option '-clscale' (or
+</FONT></I><I><FONT COLOR="#B22222">// with the option Mesh.CharacteristicLengthFactor). For example,
+</FONT></I><I><FONT COLOR="#B22222">// with:
 </FONT></I><I><FONT COLOR="#B22222">//
 </FONT></I><I><FONT COLOR="#B22222">// &gt; gmsh t5 -clscale 1
 </FONT></I><I><FONT COLOR="#B22222">//
@@ -671,6 +672,11 @@ Function CheeseHole
   l7 = newreg; Line Loop(l7) = {c2,c7,c12};   Ruled Surface(newreg) = {l7};
   l8 = newreg; Line Loop(l8) = {-c6,-c9,c2};  Ruled Surface(newreg) = {l8};
 
+<I><FONT COLOR="#B22222">// Warning: surface meshes are generated by projecting a 2D mesh in
+</FONT></I><I><FONT COLOR="#B22222">// the mean plane of the surface. This gives nice results only if the
+</FONT></I><I><FONT COLOR="#B22222">// surface curvature is small enough. Otherwise you will have to cut
+</FONT></I><I><FONT COLOR="#B22222">// the surface in pieces.
+</FONT></I>
 <I><FONT COLOR="#B22222">// Arrays of variables can be manipulated in the same way as classical
 </FONT></I><I><FONT COLOR="#B22222">// variables. Warning: accessing an uninitialized element in an array
 </FONT></I><I><FONT COLOR="#B22222">// will produce an unpredictable result. Note that whole arrays can
@@ -1170,18 +1176,14 @@ EndFor
 </FONT></I>
 Include &quot;view3.pos&quot; ;
 
-<I><FONT COLOR="#B22222">// Plugins can be controlled as other options in Gmsh. For example,
-</FONT></I><I><FONT COLOR="#B22222">// the CutMap plugin extracts an isovalue surface from a 3D scalar
-</FONT></I><I><FONT COLOR="#B22222">// view. The plugin can either be called from the graphical interface
-</FONT></I><I><FONT COLOR="#B22222">// (right click on the view button, then Plugins-&gt;CutMap), or from
-</FONT></I><I><FONT COLOR="#B22222">// the command file, as is shown below.
-</FONT></I>
-<I><FONT COLOR="#B22222">// This sets the optional parameter A of the CutMap plugin to the
-</FONT></I><I><FONT COLOR="#B22222">// value 0.67 (see the About in the graphical interface for the
-</FONT></I><I><FONT COLOR="#B22222">// documentation of each plugin), and runs the plugin:
+<I><FONT COLOR="#B22222">// Plugins can be controlled in the same way as other options in
+</FONT></I><I><FONT COLOR="#B22222">// Gmsh. For example, the CutMap plugin (which extracts an isovalue
+</FONT></I><I><FONT COLOR="#B22222">// surface from a 3D scalar view) can either be called from the
+</FONT></I><I><FONT COLOR="#B22222">// graphical interface (right click on the view button, then
+</FONT></I><I><FONT COLOR="#B22222">// Plugins-&gt;CutMap), or from the command file:
 </FONT></I>
-Plugin(CutMap).A = 0.67 ; 
-Plugin(CutMap).iView = 0 ; <I><FONT COLOR="#B22222">//select View[0] as the working view
+Plugin(CutMap).A = 0.67 ; <I><FONT COLOR="#B22222">// iso-value level
+</FONT></I>Plugin(CutMap).iView = 0 ; <I><FONT COLOR="#B22222">// source view is View[0]
 </FONT></I>Plugin(CutMap).Run ; 
 
 <I><FONT COLOR="#B22222">// The following runs the CutPlane plugin: