diff --git a/lib/geocoder/calculations.rb b/lib/geocoder/calculations.rb
index ae912dde5c11d2fd0d6f6461d8564649a3678ecf..832ef3e0015d9a3981b43f8ad53d4a0abafa305d 100644
--- a/lib/geocoder/calculations.rb
+++ b/lib/geocoder/calculations.rb
@@ -271,7 +271,7 @@ module Geocoder
     ##
     # Convert kilometers to nautical miles.
     #
-    def to_nauticalmiles(km)
+    def to_nautical_miles(km)
       km * km_in_nm
     end
 
@@ -287,7 +287,7 @@ module Geocoder
 	when :mi
         	to_miles(EARTH_RADIUS)
 	when :nm
-      		to_nauticalmiles(EARTH_RADIUS)
+      		to_nautical_miles(EARTH_RADIUS)
       end
     end