Another curious circumstance connected with this "castoreum" is, that as soon as one beaver has deposited any of it on the ground, the beavers from another lodge go to the spot, and after covering it with earth and leaves, deposit their own "castoreum" on it.  When they have gone away, others in turn perform the same operation; and thus the process goes on till a heap four or five feet in height has been raised.  No one has as yet been able to ascertain the object of this proceeding.  It gives the trapper, however, the means of catching the poor creatures--means which they would undoubtedly withhold, if they had the power.  Like human beings, they are sufferers from their own acts.