diff --git a/lib/slide_helper.rb b/lib/slide_helper.rb
index a0ac6562f725afaab2260df53e9bbce5960ce240..3ba1b2af38cad7817045965ca8b2da7431559eb4 100644
--- a/lib/slide_helper.rb
+++ b/lib/slide_helper.rb
@@ -132,6 +132,10 @@ module SlideHelper
             @next_mov_scale = 1
             @next_slide_scale = 1
         end
+
+        def to_s
+          "x = #{@x}, y = #{@y}"
+        end
     end
 
     @@pos = SlidePosition.new
@@ -257,12 +261,13 @@ module SlideHelper
     end
 
     def impress_bookmark(args)
+      puts "Bookmark #{args} #{@@pos}"
       @@bookmarks[args] = @@pos.clone
       ''
     end
 
     def impress_goto(args)
-        @@pos = @@bookmarks[args]
+        @@pos = @@bookmarks[args].clone
         "!SLIDE unclickable x=#{@@pos.x} y=#{@@pos.y} scale=#{@@pos.slide_scale} #{args}"
     end