diff --git a/Writing-your-own-publisher.md b/Writing-your-own-publisher.md
index 7939eac..794f1b2 100644
--- a/Writing-your-own-publisher.md
+++ b/Writing-your-own-publisher.md
@@ -30,7 +30,6 @@ public:
 
 
 private:
-  size_t num_cameras_;
   std::ofstream events_text_file_;
 };