--- a/ThumbWheel.st	Sat Apr 02 17:08:55 2016 +0200
+++ b/ThumbWheel.st	Sat Apr 02 17:08:58 2016 +0200
@@ -11,6 +11,8 @@
 "
 "{ Package: 'stx:libwidg2' }"
 
+"{ NameSpace: Smalltalk }"
+
 View subclass:#ThumbWheel
 	instanceVariableNames:'orientation synchronousOperation thumbPosition thumbColor
 		thumbShadowColor thumbLightColor thumbEnteredColor tallyLevel
@@ -744,12 +746,12 @@
     |ppmm|
 
     preferredExtent isNil ifTrue:[
-	ppmm := self graphicsDevice pixelPerMillimeter.
-	orientation == #vertical ifTrue:[
-	    preferredExtent := (ppmm * (5 @ 30)) rounded
-	] ifFalse:[
-	    preferredExtent := (ppmm * (30 @ 5)) rounded
-	].
+        ppmm := device pixelPerMillimeter.
+        orientation == #vertical ifTrue:[
+            preferredExtent := (ppmm * (5 @ 30)) rounded
+        ] ifFalse:[
+            preferredExtent := (ppmm * (30 @ 5)) rounded
+        ].
     ].
 
     ^ preferredExtent
@@ -769,3 +771,4 @@
 version
     ^ '$Header$'
 ! !
+