--- a/src/snapshot.rs	Sat Sep 02 19:55:10 2017 +0200
+++ b/src/snapshot.rs	Sun Sep 03 13:16:58 2017 +0200
@@ -40,13 +40,23 @@
     }
 
     pub fn delete(&mut self, ss: Snapshot) {
+        self.map.remove(&ss);
         if self.oldest == ss {
-            self.oldest += 1;
+            self.oldest = self.newest;
+            for (seq, _) in self.map.iter() {
+                if *seq < self.oldest {
+                    self.oldest = *seq;
+                }
+            }
         }
         if self.newest == ss {
-            self.newest -= 1;
+            self.newest = self.oldest;
+            for (seq, _) in self.map.iter() {
+                if *seq > self.newest {
+                    self.newest = *seq;
+                }
+            }
         }
-        self.map.remove(&ss);
     }
 
     pub fn empty(&self) -> bool {