diff --git a/tutorial/t6.geo b/tutorial/t6.geo
index 288ae53cee7e24671bc90515e218d3038ca2793f..4ef01d1f3b0a74fee22d1ed1fb31e6532e4853f2 100644
--- a/tutorial/t6.geo
+++ b/tutorial/t6.geo
@@ -6,252 +6,30 @@
  *
  *********************************************************************/
 
-// We start by defining a more complex geometry, using the same
-// commands as in the previous examples:
+// We use the geometry from the first tutorial as a basis for this
+// tutorial:
+Include "t1.geo";
 
-r_int  = 0.05 ;
-r_ext  = 0.051 ;
-r_far  = 0.125 ;
-r_inf  = 0.4 ;
-phi1   = 30. * (Pi/180.) ;
-angl   = 45. * (Pi/180.) ;
+// Put 20 equidistant points on curve 4
+Transfinite Line{4} = 20 ; 
 
-nbpt_phi   = 5 ; nbpt_int   = 20 ;
-nbpt_arc1  = 10 ; nbpt_arc2  = 10 ;
-nbpt_shell = 10 ; nbpt_far   = 25 ; nbpt_inf = 15 ;
+// Put 20 points with a refinement toward the extremities on curve 2
+Transfinite Line{2} = 20 Using Bump 0.05;
 
-lc0 = 0.1 ; lc1 = 0.1 ; lc2 = 0.3 ;
+// Put 30 points following a geometric progression on curve 1
+// (reversed) and on curve 3
+Transfinite Line{-1,3} = 30 Using Progression 1.2;
 
-Point(1) = {0,     0, 0, lc0} ;
-Point(2) = {r_int, 0, 0, lc0} ;
-Point(3) = {r_ext, 0, 0, lc1} ;
-Point(4) = {r_far, 0, 0, lc2} ;
-Point(5) = {r_inf, 0, 0, lc2} ;
-Point(6) = {0, 0,  r_int, lc0} ;
-Point(7) = {0, 0,  r_ext, lc1} ;
-Point(8) = {0, 0,  r_far, lc2} ;
-Point(9) = {0, 0,  r_inf, lc2} ;
+// Define the Surface as transfinite, by specifying the four corners
+// of the transfinite interpolation
+Transfinite Surface{6} = {1,2,3,4};
 
-Point(10) = {r_int*Cos(phi1), r_int*Sin(phi1), 0, lc0} ;
-Point(11) = {r_ext*Cos(phi1), r_ext*Sin(phi1), 0, lc1} ;
-Point(12) = {r_far*Cos(phi1), r_far*Sin(phi1), 0, lc2} ;
-Point(13) = {r_inf*Cos(phi1), r_inf*Sin(phi1), 0, lc2} ;
+// Please note that the list on the right hand side refers to points,
+// not curves. The way triangles are generated can be controlled by
+// appending "Left", "Right" or "Alternate" after the list.
 
-Point(14) = {r_int/2, 0, 0, lc2} ;
-Point(15) = {r_int/2*Cos(phi1), r_int/2*Sin(phi1), 0, lc2} ;
-Point(16) = {r_int/2, 0, r_int/2, lc2} ;
-Point(17) = {r_int/2*Cos(phi1), r_int/2*Sin(phi1), r_int/2, lc2} ;
-Point(18) = {0, 0, r_int/2, lc2} ;
-Point(19) = {r_int*Cos(angl), 0, r_int*Sin(angl), lc2} ;
-Point(20) = {r_int*Cos(angl)*Cos(phi1), r_int*Cos(angl)*Sin(phi1),
-	     r_int*Sin(angl), lc2} ;
-Point(21) = {r_ext*Cos(angl), 0, r_ext*Sin(angl), lc2} ;
-Point(22) = {r_ext*Cos(angl)*Cos(phi1), r_ext*Cos(angl)*Sin(phi1),
-	     r_ext*Sin(angl), lc2} ;
-Point(23) = {r_far*Cos(angl), 0, r_far*Sin(angl), lc2} ;
-Point(24) = {r_far*Cos(angl)*Cos(phi1), r_far*Cos(angl)*Sin(phi1),
-	     r_far*Sin(angl), lc2} ;
-Point(25) = {r_inf, 0, r_inf, lc2} ;
-Point(26) = {r_inf*Cos(phi1), r_inf*Sin(phi1),  r_inf, lc2} ;
+// Recombine the transfinite mesh into quads
+Recombine Surface{6};
 
-Circle(1) = {2,1,19};  Circle(2) = {19,1,6};  Circle(3) = {3,1,21};
-Circle(4) = {21,1,7};  Circle(5) = {4,1,23};  Circle(6) = {23,1,8};   
-Line(7)   = {5,25};    Line(8)   = {25,9};
-Circle(9) = {10,1,20}; Circle(10)= {20,1,6};  Circle(11) = {11,1,22};
-Circle(12)= {22,1,7};  Circle(13)= {12,1,24}; Circle(14) = {24,1,8};
-Line(15)  = {13,26};   Line(16)  = {26,9};
-Circle(17)= {19,1,20}; Circle(18)= {21,1,22}; Circle(19) = {23,1,24};
-Circle(20)= {25,1,26}; Circle(21)= {2,1,10};  Circle(22) = {3,1,11};  
-Circle(23)= {4,1,12};  Circle(24)= {5,1,13};
-
-Line(25) = {1,14};  Line(26) = {14,2};  Line(27) = {2,3};
-Line(28) = {3,4};   Line(29) = {4,5};   Line(30) = {1,15};
-Line(31) = {15,10}; Line(32) = {10,11}; Line(33) = {11,12};
-Line(34) = {12,13}; Line(35) = {14,15}; Line(36) = {14,16};
-Line(37) = {15,17}; Line(38) = {16,17}; Line(39) = {18,16};
-Line(40) = {18,17}; Line(41) = {1,18};  Line(42) = {18,6};
-Line(43) = {6,7};   Line(44) = {16,19}; Line(45) = {19,21};
-Line(46) = {21,23}; Line(47) = {23,25}; Line(48) = {17,20};
-Line(49) = {20,22}; Line(50) = {22,24}; Line(51) = {24,26};
-Line(52) = {7,8};   Line(53) = {8,9};
-
-Line Loop(54) = {39,-36,-25,41};  Ruled Surface(55) = {54};
-Line Loop(56) = {44,-1,-26,36};   Ruled Surface(57) = {56};
-Line Loop(58) = {3,-45,-1,27};    Ruled Surface(59) = {58};
-Line Loop(60) = {5,-46,-3,28};    Ruled Surface(61) = {60};
-Line Loop(62) = {7,-47,-5,29};    Ruled Surface(63) = {62};
-Line Loop(64) = {-2,-44,-39,42};  Ruled Surface(65) = {64};
-Line Loop(66) = {-4,-45,2,43};    Ruled Surface(67) = {66};
-Line Loop(68) = {-6,-46,4,52};    Ruled Surface(69) = {68};
-Line Loop(70) = {-8,-47,6,53};    Ruled Surface(71) = {70};
-Line Loop(72) = {-40,-41,30,37};  Ruled Surface(73) = {72};
-Line Loop(74) = {48,-9,-31,37};   Ruled Surface(75) = {74};
-Line Loop(76) = {49,-11,-32,9};   Ruled Surface(77) = {76};
-Line Loop(78) = {-50,-11,33,13};  Ruled Surface(79) = {78};
-Line Loop(80) = {-51,-13,34,15};  Ruled Surface(81) = {80};
-Line Loop(82) = {10,-42,40,48};   Ruled Surface(83) = {82};
-Line Loop(84) = {12,-43,-10,49};  Ruled Surface(85) = {84};
-Line Loop(86) = {14,-52,-12,50};  Ruled Surface(87) = {86};
-Line Loop(88) = {16,-53,-14,51};  Ruled Surface(89) = {88};
-Line Loop(90) = {-30,25,35};      Ruled Surface(91) = {90};
-Line Loop(92) = {-40,39,38};      Ruled Surface(93) = {92};
-Line Loop(94) = {37,-38,-36,35};  Ruled Surface(95) = {94};
-Line Loop(96) = {-48,-38,44,17};  Ruled Surface(97) = {96};
-Line Loop(98) = {18,-49,-17,45};  Ruled Surface(99) = {98};
-Line Loop(100) = {19,-50,-18,46}; Ruled Surface(101) = {100};
-Line Loop(102) = {20,-51,-19,47}; Ruled Surface(103) = {102};
-Line Loop(104) = {-2,17,10};      Ruled Surface(105) = {104};
-Line Loop(106) = {-9,-21,1,17};   Ruled Surface(107) = {106};
-Line Loop(108) = {-4,18,12};      Ruled Surface(109) = {108};
-Line Loop(110) = {-11,-22,3,18};  Ruled Surface(111) = {110};
-Line Loop(112) = {-13,-23,5,19};  Ruled Surface(113) = {112};
-Line Loop(114) = {-6,19,14};      Ruled Surface(115) = {114};
-Line Loop(116) = {-15,-24,7,20};  Ruled Surface(117) = {116};
-Line Loop(118) = {-8,20,16};      Ruled Surface(119) = {118};
-Line Loop(120) = {-31,-35,26,21}; Ruled Surface(121) = {120};
-Line Loop(122) = {32,-22,-27,21}; Ruled Surface(123) = {122};
-Line Loop(124) = {33,-23,-28,22}; Ruled Surface(125) = {124};
-Line Loop(126) = {34,-24,-29,23}; Ruled Surface(127) = {126};
-
-Surface Loop(128) = {93,-73,-55,95,-91};
-Volume(129) = {128}; // int
-Surface Loop(130) = {107,-75,-97,95,57,121};
-Volume(131) = {130}; // int b
-Surface Loop(132) = {105,-65,-97,-83,-93};
-Volume(133) = {132}; // int h
-Surface Loop(134) = {99,-111,77,123,59,107};
-Volume(135) = {134}; // shell b
-Surface Loop(136) = {99,-109,67,105,85};
-Volume(137) = {136}; // shell h
-Surface Loop(138) = {113,79,-101,-111,-125,-61};
-Volume(139) = {138}; // ext b
-Surface Loop(140) = {115,-69,-101,-87,-109};
-Volume(141) = {140}; // ext h
-Surface Loop(142) = {103,-117,-81,113,127,63};
-Volume(143) = {142}; // inf b
-Surface Loop(144) = {89,-119,71,103,115};
-Volume(145) = {144}; // inf h
-
-// Once the geometry is defined, we then add transfinite mesh commands
-// in order to explicitly define a structured mesh.
-
-// 1. Transfinite line commands specify the number of points on the
-// curves and their distribution (`Progression 2' means that each line
-// element in the series will be twice as long as the preceding one):
-
-Transfinite Line{35,21,22,23,24,38,17,18,19,20} = nbpt_phi ;
-Transfinite Line{31,26,48,44,42} = nbpt_int Using Progression 0.88;
-Transfinite Line{41,37,36,9,11,1,3,13,5,15,7} = nbpt_arc1 ;
-Transfinite Line{30,25,40,39,10,2,12,4,14,6,16,8} = nbpt_arc2 ;
-Transfinite Line{32,27,49,45,43} = nbpt_shell ;
-Transfinite Line{33,28,46,50,52} = nbpt_far Using Progression 1.2 ;
-Transfinite Line{34,29,51,47,53} = nbpt_inf Using Progression 1.05;
-
-// 2. Transfinite surfaces are defined by an ordered list of the
-// points on their boundary (the ordering of these points defines the
-// ordering of the mesh elements). Note that a transfinite surface can
-// only have 3 or 4 sides:
-
-Transfinite Surface{55} = {1,14,16,18};
-Transfinite Surface{57} = {14,2,19,16};
-Transfinite Surface{59} = {2,3,21,19};
-Transfinite Surface{61} = {3,4,23,21};
-Transfinite Surface{63} = {4,5,25,23};
-Transfinite Surface{73} = {1,15,17,18};
-Transfinite Surface{75} = {15,10,20,17};
-Transfinite Surface{77} = {10,11,22,20};
-Transfinite Surface{79} = {11,12,24,22};
-Transfinite Surface{81} = {12,13,26,24};
-Transfinite Surface{65} = {18,16,19,6};
-Transfinite Surface{67} = {6,19,21,7};
-Transfinite Surface{69} = {7,21,23,8};
-Transfinite Surface{71} = {8,23,25,9};
-Transfinite Surface{83} = {17,18,6,20};
-Transfinite Surface{85} = {20,6,7,22};
-Transfinite Surface{87} = {22,7,8,24};
-Transfinite Surface{89} = {24,8,9,26};
-Transfinite Surface{91} = {1,14,15};
-Transfinite Surface{95} = {15,14,16,17};
-Transfinite Surface{93} = {18,16,17};
-Transfinite Surface{121} = {15,14,2,10};
-Transfinite Surface{97} = {17,16,19,20};
-Transfinite Surface{123} = {10,2,3,11};
-Transfinite Surface{99} = {20,19,21,22};
-Transfinite Surface{107} = {10,2,19,20};
-Transfinite Surface{105} = {6,20,19};
-Transfinite Surface{109} = {7,22,21};
-Transfinite Surface{111} = {11,3,21,22};
-Transfinite Surface{101} = {22,21,23,24};
-Transfinite Surface{125} = {11,3,4,12};
-Transfinite Surface{115} = {8,24,23};
-Transfinite Surface{113} = {24,12,4,23};
-Transfinite Surface{127} = {12,13,5,4};
-Transfinite Surface{103} = {24,23,25,26};
-Transfinite Surface{119} = {9,26,25};
-Transfinite Surface{117} = {13,5,25,26};
-
-// 3. Transfinite volumes are also defined by an ordered list of the
-// points on their boundary (the ordering defines the ordering of the
-// mesh elements).  A transfinite volume can only have 6 or 8 faces:
-
-Transfinite Volume{129} = {1,14,15,18,16,17};
-Transfinite Volume{131} = {17,16,14,15,20,19,2,10};
-Transfinite Volume{133} = {18,17,16,6,20,19};
-Transfinite Volume{135} = {10,2,19,20,11,3,21,22};
-Transfinite Volume{137} = {6,20,19,7,22,21};
-Transfinite Volume{139} = {11,3,4,12,22,21,23,24};
-Transfinite Volume{141} = {7,22,21,8,24,23};
-Transfinite Volume{143} = {12,4,5,13,24,23,25,26};
-Transfinite Volume{145} = {8,24,23,9,26,25};
-
-// As with Extruded meshes, the `Recombine' command tells Gmsh to
-// recombine the simplices into quadrangles, prisms or hexahedra when
-// possible:
-
-Recombine Surface {55:127};
-
-// We finish by defing some physical entities:
-
-VolInt           = 1000 ;
-SurfIntPhi0      = 1001 ;  SurfIntPhi1      = 1002 ;
-SurfIntZ0        = 1003 ;
-
-VolShell         = 2000 ;
-SurfShellInt     = 2001 ;  SurfShellExt     = 2002 ;
-SurfShellPhi0    = 2003 ;  SurfShellPhi1    = 2004 ;
-SurfShellZ0      = 2005 ;
-LineShellIntPhi0 = 2006 ;
-LineShellIntPhi1 = 2007 ;  LineShellIntZ0   = 2008 ;
-PointShellInt    = 2009 ;
-
-VolExt           = 3000 ;
-VolInf           = 3001 ;
-SurfInf          = 3002 ;
-SurfExtInfPhi0   = 3003 ;  SurfExtInfPhi1   = 3004 ;
-SurfExtInfZ0     = 3005 ;
-SurfInfRight     = 3006 ;
-SurfInfTop       = 3007 ;
-
-Physical Volume  (VolInt)           = {129,131,133} ;
-Physical Surface (SurfIntPhi0)      = {55,57,65} ;
-Physical Surface (SurfIntPhi1)      = {73,75,83} ;
-Physical Surface (SurfIntZ0)        = {91,121} ;
-
-Physical Volume  (VolShell)         = {135,137} ;
-Physical Surface (SurfShellInt)     = {105,107} ;
-Physical Surface (SurfShellExt)     = {109,111} ;
-Physical Surface (SurfShellPhi0)    = {59,67} ;
-Physical Surface (SurfShellPhi1)    = {77,85} ;
-Physical Surface (SurfShellZ0)      = {123} ;
-Physical Line    (LineShellIntPhi0) = {1,2} ;
-Physical Line    (LineShellIntPhi1) = {9,10} ;
-Physical Line    (LineShellIntZ0)   = 21 ;
-//Physical Point   (PointShellInt)    = 6 ;
-
-Physical Volume  (VolExt)           = {139,141} ;
-Physical Volume  (VolInf)           = {143,145} ;
-Physical Surface (SurfExtInfPhi0)   = {61,63,69,71} ;
-Physical Surface (SurfExtInfPhi1)   = {79,87,81,89} ;
-Physical Surface (SurfExtInfZ0)     = {125,127} ;
-Physical Surface (SurfInfRight)     = {117} ;
-Physical Surface (SurfInfTop)       = {119} ;
+// Apply an elliptic smoother to the grid
+Mesh.Smoothing = 100;