diff --git a/lib/parfait/behaviour.rb b/lib/parfait/behaviour.rb
index 492c3858..66b3032d 100644
--- a/lib/parfait/behaviour.rb
+++ b/lib/parfait/behaviour.rb
@@ -1,8 +1,17 @@
-# Behaviour is something that has methods, basically class and modules superclass
-
-# instance_methods is the attribute in the including class that has the methods
-
 module Parfait
+  # Behaviour is the old smalltalk name for the duperclass of class and meta_class
+  #
+  # Classes and meta_classes are in fact very similar, in that they manage
+  # - the type of instances
+  # - the methods for instances
+  #
+  # The main way they differ is that Classes manage type for a class of objects (ie many)
+  # whereas meta_class, or singleton_class manages the type of only one object (here a class)
+  #
+  # Singleton classes can manage the type/methods of any single object, and in the
+  # future off course they will, just not yet. Most single objects don't need that,
+  # only Classes and Modules _always _ do, so that's where we start.
+  #
   class Behaviour < Object
 
     attr_reader :instance_type , :instance_methods
diff --git a/lib/parfait/meta_class.rb b/lib/parfait/meta_class.rb
index da4324e7..cbcfb64b 100644
--- a/lib/parfait/meta_class.rb
+++ b/lib/parfait/meta_class.rb
@@ -43,6 +43,12 @@ module Parfait
       inspect
     end
 
+    # adding an instance changes the instance_type to include that variable
+    def add_instance_variable( name , type)
+      super(name,type)
+      @clazz.set_type(@instance_type)
+    end
+
     # Nil name means no superclass, and so nil returned
     def super_class
       return nil
diff --git a/lib/risc/parfait_adapter.rb b/lib/risc/parfait_adapter.rb
index dd527a98..36dfd265 100644
--- a/lib/risc/parfait_adapter.rb
+++ b/lib/risc/parfait_adapter.rb
@@ -85,14 +85,14 @@ module Parfait
     # 0 -based index
     def get_internal_word(index)
       return @type if index == Parfait::TYPE_INDEX
-      name = Parfait.name_for_index(self , index)
+      name = self.type.names[index]
       return nil unless name
       instance_eval("@#{name}")
     end
 
     # 0 -based index
     def set_internal_word(index , value)
-      name = Parfait.name_for_index(self , index)
+      name = self.type.names[index] #unless name.is_a?(Symbol)
       raise "not sym for #{index} in #{self}:#{self.type}:#{name.class}" unless name.is_a?(Symbol)
       instance_eval("@#{name}=value" )
       value
@@ -100,16 +100,6 @@ module Parfait
 
   end
 
-  def self.name_for_index(object , index)
-    return :type if index == 0
-    clazz = object.class.name.split("::").last.to_sym
-    cl = self.type_names[clazz]
-    keys = cl.keys
-    keys[index - 1] # -1 because type is excluded in the lists (FIX)
-    # FIXME Now that we use instance variables in parfait, they should be parsed
-    # and the type_names generated automatically
-  end
-
   # new list from ruby array to be precise
   def self.new_list array
     list = Parfait::List.new
diff --git a/test/parfait/test_meta_class.rb b/test/parfait/test_meta_class.rb
index 3a284194..71d67b1b 100644
--- a/test/parfait/test_meta_class.rb
+++ b/test/parfait/test_meta_class.rb
@@ -36,15 +36,18 @@ module Parfait
       assert_raises{ @try.add_instance_method(nil)}
     end
     def test_add_instance_variable_changes_type
-      before = @space.get_class.instance_type
-      @space.get_class.add_instance_variable(:counter , :Integer)
-      assert before != @space.get_class.instance_type
+      before = @try.instance_type
+      @try.add_instance_variable(:counter , :Integer)
+      assert before != @try.instance_type
     end
     def test_add_instance_variable_changes_type_hash
-      before = @space.get_class.instance_type.hash
-      @space.get_class.add_instance_variable(:counter , :Integer)
-      assert before != @space.get_class.instance_type.hash
+      before = @try.instance_type.hash
+      @try.add_instance_variable(:counter , :Integer)
+      assert before != @try.instance_type.hash
+    end
+    def test_add_instance_variable_changes_class_type
+      @try.add_instance_variable(:counter , :Integer)
+      assert_equal @try.clazz.type , @try.instance_type
     end
-
   end
 end
diff --git a/test/risc/interpreter/class/test_class_inst.rb b/test/risc/interpreter/class/test_class_inst.rb
index fdfe4b2d..e549102a 100644
--- a/test/risc/interpreter/class/test_class_inst.rb
+++ b/test/risc/interpreter/class/test_class_inst.rb
@@ -1,7 +1,7 @@
 require_relative "../helper"
 
 module Risc
-  class InterpreterSetters < MiniTest::Test
+  class InterpreterGetters < MiniTest::Test
     include Ticker
 
     def setup
@@ -19,7 +19,7 @@ module Risc
 MAIN
       super
     end
-
+#Space type is wrong, shold be same as meta_class.instance_type
     def test_chain
       #show_main_ticks # get output of what is
       run_input @string_input
diff --git a/test/risc/interpreter/class/test_class_inst_set.rb b/test/risc/interpreter/class/test_class_inst_set.rb
index 32b0c2f1..a50b7ef9 100644
--- a/test/risc/interpreter/class/test_class_inst_set.rb
+++ b/test/risc/interpreter/class/test_class_inst_set.rb
@@ -23,7 +23,7 @@ MAIN
       super
     end
 
-    def est_chain
+    def test_chain
       #show_main_ticks # get output of what is
       run_input @string_input
       assert_equal 5 , get_return
diff --git a/test/vool/class_send/test_class_instance.rb b/test/vool/class_send/test_class_instance.rb
index 71767e59..f34ff75d 100644
--- a/test/vool/class_send/test_class_instance.rb
+++ b/test/vool/class_send/test_class_instance.rb
@@ -12,7 +12,7 @@ module Vool
             return @inst
           end
           def main(arg)
-            return Space.one_plus
+            return Space.some_inst
           end
         end
       eos
@@ -20,16 +20,34 @@ module Vool
 
     def setup
       ret = RubyX::RubyXCompiler.new(RubyX.default_test_options).ruby_to_mom(class_main)
-      @ins = ret.compilers.find{|c|c.callable.name==:some_inst}.mom_instructions.next
+      @compiler = ret.compilers.find{|c|c.callable.name==:some_inst}
+      @main = ret.compilers.find{|c|c.callable.name==:main}
+      @ins = @compiler.mom_instructions.next
     end
     def test_class_inst
-        space_class = Parfait.object_space.get_class
-        assert_equal :Space , space_class.name
-        names = space_class.meta_class.instance_type.names
-        assert names.index_of(:inst) , names
+      space_class = Parfait.object_space.get_class
+      assert_equal :Space , space_class.name
+      names = space_class.meta_class.instance_type.names
+      assert names.index_of(:inst) , names
+    end
+    def test_compiler
+      assert_equal Mom::MethodCompiler, @compiler.class
+      assert_equal Parfait::Type, @compiler.callable.self_type.class
+      assert_equal 6, @compiler.callable.self_type.names.index_of(:inst) , @compiler.callable.self_type.names
     end
     def test_array
-      check_array   [SlotLoad, ReturnJump, Label, ReturnSequence, Label]  , @ins
+      check_array [SlotLoad, ReturnJump, Label, ReturnSequence, Label]  , @ins
+    end
+    def test_main_array
+      check_array [MessageSetup, ArgumentTransfer, SimpleCall, SlotLoad, ReturnJump ,
+                    Label, ReturnSequence, Label]  , @main.mom_instructions.next
+    end
+    def test_main_args
+      args = @main.mom_instructions.next(2)
+      assert_equal Parfait::Class , args.receiver.known_object.class
+      assert_equal :Space , args.receiver.known_object.name
+      assert_equal :some_inst , args.receiver.known_object.type.method_names.first
+      assert_equal :inst , args.receiver.known_object.type.names.last
     end
     def test_load_inst
       assert_equal SlotLoad,  @ins.class
diff --git a/test/vool/class_send/test_class_send_inherited.rb b/test/vool/class_send/test_class_send_inherited.rb
index f78641ae..54c431f5 100644
--- a/test/vool/class_send/test_class_send_inherited.rb
+++ b/test/vool/class_send/test_class_send_inherited.rb
@@ -40,7 +40,7 @@ module Vool
       assert_equal SimpleCall,  @ins.next(2).class
       assert_equal :one_plus,  @ins.next(2).method.name
       assert_equal Parfait::Type,  @ins.next(2).method.self_type.class
-      assert_equal :Object,  @ins.next(2).method.self_type.object_class.name
+      assert_equal :Class,  @ins.next(2).method.self_type.object_class.name
     end
   end
 end