         @logger.debug("Initializing")
 
         @density = 10  # The density of the environment's medium. 
+        @gravitationalConstant = 0.5
 
 
     # Update the elements with the effects of the given number of milliseconds


        return element.direction.scale(-m)


# 
# An abstract base class for any drawable thing.

        for element in elements

            # Find the net force on the element.
            forces = [
                element.velocity(),
                @drag(element),
                @gravity(element)
            ]

            resultant = forces.reduce (t, s) -> t.sum(s)    #FIXME: not portable

