diff --git a/CHANGES.md b/CHANGES.md
index 72cb6fb29654..95d07f133d0d 100644
--- a/CHANGES.md
+++ b/CHANGES.md
@@ -18,6 +18,7 @@ Change Log
 * Added `PolygonGraphics.hierarchy` for supporting polygons with holes via data sources.
 * `GeoJsonDataSource` now supports polygons with holes.
 * `ConstantProperty` can now hold any value; previously it was limited to values that implemented `equals` and `clones` functions, as well as a few special cases.
+* Fixed a bug in `EllipsoidGeodesic` that caused it to modify the `height` of the positions passed to the constructor or to to `setEndPoints`.
 * Instead of throwing an exception when there are not enough unique positions to define a geometry, creating a `Primitive` will succeed, but not render. [#2375](https://github.com/AnalyticalGraphicsInc/cesium/issues/2375)
 
 ### 1.5 - 2015-01-05
diff --git a/Source/Core/EllipsoidGeodesic.js b/Source/Core/EllipsoidGeodesic.js
index 932432412ad8..d382bd0c296f 100644
--- a/Source/Core/EllipsoidGeodesic.js
+++ b/Source/Core/EllipsoidGeodesic.js
@@ -185,10 +185,10 @@ define([
         vincentyInverseFormula(ellipsoidGeodesic, ellipsoid.maximumRadius, ellipsoid.minimumRadius,
                                start.longitude, start.latitude, end.longitude, end.latitude);
 
-        start.height = 0;
-        end.height = 0;
         ellipsoidGeodesic._start = Cartographic.clone(start, ellipsoidGeodesic._start);
         ellipsoidGeodesic._end = Cartographic.clone(end, ellipsoidGeodesic._end);
+        ellipsoidGeodesic._start.height = 0;
+        ellipsoidGeodesic._end.height = 0;
 
         setConstants(ellipsoidGeodesic);
     }
diff --git a/Specs/Core/EllipsoidGeodesicSpec.js b/Specs/Core/EllipsoidGeodesicSpec.js
index 23c73d094d22..18d3899f48f2 100644
--- a/Specs/Core/EllipsoidGeodesicSpec.js
+++ b/Specs/Core/EllipsoidGeodesicSpec.js
@@ -245,4 +245,12 @@ defineSuite([
         expect(expectedMid.longitude).toEqualEpsilon(result.longitude, CesiumMath.EPSILON13);
         expect(expectedMid.latitude).toEqualEpsilon(result.latitude, CesiumMath.EPSILON13);
     });
+
+    it('doesn\'t modify incoming cartographics', function(){
+        var start = new Cartographic(1,2,3);
+        var end = new Cartographic(2,3,4);
+        var geodesic = new EllipsoidGeodesic(start, end);
+        expect(start.height).toEqual(3);
+        expect(end.height).toEqual(4);
+    });
 });
\ No newline at end of file