diff --git a/src/multi_array_operation.cc b/src/multi_array_operation.cc
index 624807a..8b259ff 100644
--- a/src/multi_array_operation.cc
+++ b/src/multi_array_operation.cc
@@ -11,8 +11,8 @@ namespace MultiArrayTools
     MultiArrayOperationBase<T,Range>::
     MultiArrayOperationBase(MultiArray<T,Range>& ma,
 			    const Name& nm) : mArrayRef(ma),
-					      //mIndex(mArrayRef.begin()),
-					      mIibPtr(new IndexType(mArrayRef.begin())),
+					      mIndex(mArrayRef.begin()),
+					      mIibPtr(&mIndex),
 					      mNm(nm)
     {
 	mIibPtr->name(nm);
diff --git a/src/multi_array_operation.h b/src/multi_array_operation.h
index 261c5f7..fca3f78 100644
--- a/src/multi_array_operation.h
+++ b/src/multi_array_operation.h
@@ -64,7 +64,7 @@ namespace MultiArrayTools
     protected:
 
 	MultiArray<T,Range>& mArrayRef;
-	//mutable IndexType mIndex;
+	mutable IndexType mIndex;
 	IndefinitIndexBase* mIibPtr = nullptr;
 	Name mNm;
     };