diff --git a/cosserat-continuum.cc b/cosserat-continuum.cc
index 91f9a832b14baaa55ecd5371fec4df38f39c5bab..af1bf1eb5374c0465888f029d1836d77c4bf7a9b 100644
--- a/cosserat-continuum.cc
+++ b/cosserat-continuum.cc
@@ -90,7 +90,7 @@ struct NeumannFunction
     
     void evaluate(const FieldVector<double, dim>& x, FieldVector<double,3>& out) const {
         out = 0;
-        out[0] = -40*homotopyParameter_;
+        out[2] = -40*homotopyParameter_;
     }
 
     double homotopyParameter_;