Fix typo

docs/contracts.rst

@@ -774,7 +774,7 @@ The use in the JavaScript API would be as follows:
     // watch for changes
     event.watch(function(error, result){
         // result will contain various information
-        // including the argumets given to the `Deposit`
+        // including the arguments given to the `Deposit`
         // call.
         if (!error)
             console.log(result);