diff --git a/gtsam_unstable/geometry/Event.cpp b/gtsam_unstable/geometry/Event.cpp
index 09cedb512..5248241e1 100644
--- a/gtsam_unstable/geometry/Event.cpp
+++ b/gtsam_unstable/geometry/Event.cpp
@@ -21,7 +21,4 @@
 
 namespace gtsam {
 
-const double Event::Speed = 330;
-const Matrix14 Event::JacobianZ = (Matrix14() << 0,0,0,1).finished();
-
 } //\ namespace gtsam
diff --git a/gtsam_unstable/geometry/Event.h b/gtsam_unstable/geometry/Event.h
index 3c622924a..dd362c7f4 100644
--- a/gtsam_unstable/geometry/Event.h
+++ b/gtsam_unstable/geometry/Event.h
@@ -33,10 +33,6 @@ class Event {
 public:
   enum { dimension = 4 };
 
-  /// Speed of sound
-  static const double Speed;
-  static const Matrix14 JacobianZ;
-
   /// Default Constructor
   Event() :
       time_(0) {
@@ -57,6 +53,7 @@ public:
 
   // TODO we really have to think of a better way to do linear arguments
   double height(OptionalJacobian<1,4> H = boost::none) const {
+    static const Matrix14 JacobianZ = (Matrix14() << 0,0,0,1).finished();
     if (H) *H = JacobianZ;
     return location_.z();
   }
@@ -87,6 +84,7 @@ public:
   double toa(const Point3& microphone, //
       OptionalJacobian<1, 4> H1 = boost::none, //
       OptionalJacobian<1, 3> H2 = boost::none) const {
+    static const double Speed = 330;
     Matrix13 D1, D2;
     double distance = location_.distance(microphone, D1, D2);
     if (H1)
diff --git a/gtsam_unstable/geometry/tests/testEvent.cpp b/gtsam_unstable/geometry/tests/testEvent.cpp
index 433ca7e7f..0842e2146 100644
--- a/gtsam_unstable/geometry/tests/testEvent.cpp
+++ b/gtsam_unstable/geometry/tests/testEvent.cpp
@@ -45,13 +45,13 @@ TEST( Event, Constructor ) {
 //*****************************************************************************
 TEST( Event, Toa1 ) {
   Event event(0, 1, 0, 0);
-  double expected = 1 / Event::Speed;
+  double expected = 1. / 330;
   EXPECT_DOUBLES_EQUAL(expected, event.toa(microphoneAt0), 1e-9);
 }
 
 //*****************************************************************************
 TEST( Event, Toa2 ) {
-  double expectedTOA = timeOfEvent + 1 / Event::Speed;
+  double expectedTOA = timeOfEvent + 1. / 330;
   EXPECT_DOUBLES_EQUAL(expectedTOA, exampleEvent.toa(microphoneAt0), 1e-9);
 }
 
@@ -79,7 +79,7 @@ TEST( Event, Expression ) {
 
   Values values;
   values.insert(key, exampleEvent);
-  double expectedTOA = timeOfEvent + 1 / Event::Speed;
+  double expectedTOA = timeOfEvent + 1. / 330;
   EXPECT_DOUBLES_EQUAL(expectedTOA, expression.value(values), 1e-9);
 }