diff --git a/core/models/survex.py b/core/models/survex.py
index b82bd90..6c63034 100644
--- a/core/models/survex.py
+++ b/core/models/survex.py
@@ -69,7 +69,7 @@ class SurvexFile(models.Model):
 
 
 class SurvexStationLookUpManager(models.Manager):
-    """Don't know what this does, 
+    """what this does, 
     https://docs.djangoproject.com/en/dev/topics/db/managers/
     This changes the .objects thinggy to use a case-insensitive match name__iexact
     so that now SurvexStation.objects.lookup() works as a case-insensitive match
@@ -104,26 +104,27 @@ class SurvexStation(models.Model):
     def __str__(self):
         return self.name and str(self.name) or "no name"
 
-
 #
 # Single SurvexBlock
 #
-# class SurvexBlockLookUpManager(models.Manager):
-    # """Don't know what this does,  
-    # https://docs.djangoproject.com/en/dev/topics/db/managers/ 
+class SurvexBlockLookUpManager(models.Manager):
+    """what this does,  
+    https://docs.djangoproject.com/en/dev/topics/db/managers/ 
     
-    # This changes the .objects_set thinggy to use a case-insensitive match name__iexact
-    # so that now SurvexBlock.objects.lookup() works as a case-insensitive match UNUSED
-    # """
-    # def lookup(self, name):
-        # if name == "":
-            # blocknames = []
-        # else:
-            # blocknames = name.split(".")
-        # # block = SurvexBlock.objects.get(parent=None, survexfile__path=settings.SURVEX_TOPNAME)
-        # for blockname in blocknames:
-            # block = SurvexBlock.objects.get(parent=block, name__iexact=blockname)
-        # return block
+    This adds a method to the .objects thinggy to use a case-insensitive match name__iexact
+    so that now SurvexBlock.objects.lookup() works as a case-insensitive match.
+    This is used in lookup() in SurvexStationLookUpManager()  
+    which is used in Entrance().other_location() which is used in the Cave webpage
+    """
+    def lookup(self, name):
+        if name == "":
+            blocknames = []
+        else:
+            blocknames = name.split(".")
+        # block = SurvexBlock.objects.get(parent=None, survexfile__path=settings.SURVEX_TOPNAME)
+        for blockname in blocknames:
+            block = SurvexBlock.objects.get(parent=block, name__iexact=blockname)
+        return block
 
 
 class SurvexBlock(models.Model):