Whilst the greatest effort has been made to ensure the quality of this text, due to the historical nature of this content, in some rare cases there may be minor issues with legibility. In this attempt to present an elementary, and at the same time a scientific view of the subject, I have expanded several of the suggestive ideas put forward in Dynamics of Rotation by Professor Worthington, to whom is due a large debt of thanks for much liberal criticism and assistance in the earlier chapters, and for permission to borrow his article on Brennan''s Monorail.