       if t.id == thing.id
         @things.splice i, 1
         break
-    delete @thingMap[thing.id]
-    for k, t of @thingMap
+    for t in @things
       delete t.others[thing.id]
   # moves a thing based on that things velocity, handling reflection off
   # the edges of the universe

    for other in @nearby()
      influence = @affinity other
      if influence
        data = @otherData other
        influence /= Math.pow( data.distance, 2 )
        influence *= @g()
        [ xa, ya ] = data.vector influence

    now
  # the steps involved in one go of the universe's clock
  go: ->
    unless @dead
      @tick += 1
      self = @
      self.move()
      setTimeout(
        -> self.recalculateGeometries()
        0
      )
  afterGeometry: ->
    self = @
    self.die()
