diff --git a/gtsam_unstable/nonlinear/Expression-inl.h b/gtsam_unstable/nonlinear/Expression-inl.h
index 231193261..cd4bc68a7 100644
--- a/gtsam_unstable/nonlinear/Expression-inl.h
+++ b/gtsam_unstable/nonlinear/Expression-inl.h
@@ -26,6 +26,8 @@ namespace gtsam {
 
 template<typename T>
 class Expression;
+template<typename T, typename E1, typename E2>
+class MethodExpression;
 
 /**
  * Expression node. The superclass for objects that do the heavy lifting
@@ -218,8 +220,8 @@ private:
       expression1_(e1.root()), expression2_(e2.root()), f_(f) {
   }
 
-  friend class Expression<T> ;
-
+  friend class Expression<T>;
+public:
   /// Combine Jacobians
   static void combine(const Matrix& H1, const Matrix& H2,
       const JacobianMap& terms1, const JacobianMap& terms2,
@@ -288,9 +290,9 @@ public:
 
   typedef std::map<Key, Matrix> JacobianMap;
 
-  typedef boost::function<
-      T(const E1*, const E2&, boost::optional<Matrix&>,
-          boost::optional<Matrix&>)> method;
+  typedef 
+      T (E1::*method)(const E2&, boost::optional<Matrix&>,
+          boost::optional<Matrix&>) const;
 
 private:
 
@@ -326,11 +328,11 @@ public:
     if (jacobians) {
       JacobianMap terms1, terms2;
       Matrix H1, H2;
-      val = f_(expression1_->value(values, terms1),
+      val = (expression1_->value(values, terms1).*(f_))(
           expression2_->value(values, terms2), H1, H2);
       BinaryExpression<T, E1, E2>::combine(H1, H2, terms1, terms2, *jacobians);
     } else {
-      val = f_(expression1_->value(values), expression2_->value(values),
+      val = (expression1_->value(values).*(f_))(expression2_->value(values),
           boost::none, boost::none);
     }
     return val;
diff --git a/gtsam_unstable/nonlinear/Expression.h b/gtsam_unstable/nonlinear/Expression.h
index 826b2caf9..0d326dffe 100644
--- a/gtsam_unstable/nonlinear/Expression.h
+++ b/gtsam_unstable/nonlinear/Expression.h
@@ -63,7 +63,7 @@ public:
       typename MethodExpression<T, E1, E2>::method f,
       const Expression<E2>& expression2) {
     // TODO Assert that root of expressions 1 and 2 are not null.
-    root_.reset(new MethodExpression<T, E1, E2>(f, expression1, expression2));
+    root_.reset(new MethodExpression<T, E1, E2>(expression1, f, expression2));
   }
 
   /// Return keys that play in this expression
diff --git a/gtsam_unstable/nonlinear/tests/testExpression.cpp b/gtsam_unstable/nonlinear/tests/testExpression.cpp
index faad56777..8602bcbf3 100644
--- a/gtsam_unstable/nonlinear/tests/testExpression.cpp
+++ b/gtsam_unstable/nonlinear/tests/testExpression.cpp
@@ -7,7 +7,7 @@
 
  * See LICENSE for the license information
 
- * -------------------------------------------------------------------------- */
+ * -------------------------------1------------------------------------------- */
 
 /**
  * @file testExpression.cpp
@@ -60,8 +60,8 @@ TEST(BAD, test) {
   // Create expression tree
 //  MethodExpression<Point3,Pose3,Point3>::method m = &Pose3::transform_to;
 //  MethodExpression<Point3,Pose3,Point3> methodExpression(x, &Pose3::transform_to, p);
-//  Expression<Point3> p_cam(x, &Pose3::transform_to, p);
-  Expression<Point3> p_cam(transformTo, x, p);
+  Expression<Point3> p_cam(x, &Pose3::transform_to, p);
+  //Expression<Point3> p_cam(transformTo, x, p);
   Expression<Point2> projection(project, p_cam);
   Expression<Point2> uv_hat(uncalibrate<Cal3_S2>, K, projection);