diff --git a/Navigator/src/Navigator/Physics/Caen/CompassRun.cpp b/Navigator/src/Navigator/Physics/Caen/CompassRun.cpp
index 61b10fc..264663a 100644
--- a/Navigator/src/Navigator/Physics/Caen/CompassRun.cpp
+++ b/Navigator/src/Navigator/Physics/Caen/CompassRun.cpp
@@ -14,12 +14,12 @@
 namespace Navigator {
 	
 	CompassRun::CompassRun() :
-		DataSource(), m_directory("")
+		DataSource(), m_directory(""), m_startIndex(0)
 	{
 	}
 	
 	CompassRun::CompassRun(const std::string& dir) :
-		DataSource(), m_directory(dir)
+		DataSource(), m_directory(dir), m_startIndex(0)
 	{
 		CollectFiles();
 	}
@@ -87,18 +87,18 @@ namespace Navigator {
 	{
 	
 		std::pair<CompassHit, bool*> earliestHit = std::make_pair(CompassHit(), nullptr);
-		for(unsigned int i=startIndex; i<m_datafiles.size(); i++) 
+		for(unsigned int i=m_startIndex; i<m_datafiles.size(); i++) 
 		{
 			if(m_datafiles[i].CheckHitHasBeenUsed()) 
 				m_datafiles[i].GetNextHit();
 	
 			if(m_datafiles[i].IsEOF()) 
 			{
-				if(i == startIndex)
-					startIndex++;
+				if(i == m_startIndex)
+					m_startIndex++;
 				continue;
 			} 
-			else if(i == startIndex) 
+			else if(i == m_startIndex) 
 			{
 				earliestHit = std::make_pair(m_datafiles[i].GetCurrentHit(), m_datafiles[i].GetUsedFlagPtr());
 			} 
diff --git a/Navigator/src/Navigator/Physics/Caen/CompassRun.h b/Navigator/src/Navigator/Physics/Caen/CompassRun.h
index 4e08753..68dcd6a 100644
--- a/Navigator/src/Navigator/Physics/Caen/CompassRun.h
+++ b/Navigator/src/Navigator/Physics/Caen/CompassRun.h
@@ -38,7 +38,7 @@ namespace Navigator {
 		const std::string m_extension = ".bin";
 
 		std::vector<CompassFile> m_datafiles;
-		unsigned int startIndex; //this is the file we start looking at; increases as we finish files.
+		unsigned int m_startIndex; //this is the file we start looking at; increases as we finish files.
 
 		ShiftMap m_smap;