       # update the scaling function
       #
       @y = d3.scale.linear().
-        domain([0, max_height * 1.2]).
-        range([0, @height * .9])
+        domain([0, max_height * 1.25]).
+        range([0, @height * .90])
 
       # refresh the unit squares
       #

      #
      @nodes.data(@module.nodes.models, (d) -> d.get('id')).
        transition().duration(500).
        attr("y", (d) => @y d.y_offset())

      # then resize the rectangles
      #

  # Helper classes
  #
  Node: class extends Backbone.Model
    @width: 40
    @horizontal_spacing: 400

    initialize: =>
      # shortcut to access the collection objects
