The way Cæsar worked his tides crossing the English Channel when about to invade Britain in 55 B.C., or the way William the Conqueror a thousand years later wrestled with the same problem but in different ships--these and like matters cannot but appeal to anyone who is gifted with imagination and a keen desire for knowledge. And then--perhaps some will find it the most interesting of all--there comes that wonderful story of the dawn and rise of the navigational science which to-day enables our biggest ships to make passages across the ocean with the regularity of the train, and to make a landfall with an exactness that is nothing short of marvellous considering that the last land was left weeks ago. It is a story that is irresistible in its appeal for our consideration, firstly because of its ultimate value to the progress of nations, and secondly because no finer example could be afforded us of the persistency of human endeavour to overcome very considerable obstacles. It is a little difficult just at first to place oneself in the position of those navigators of the early centuries. To-day we are so accustomed to modern navigational methods, we have been wont so long to rely on them for finding our way across the sea, that it requires a great effort of the imagination to conceive of men crossing the Atlantic and other oceans--not to speak of long coasting voyages--without chart or compass, sextant or log-line. There are many names in history which very rightly have won the unstinted applause of humanity irrespective of national boundaries. These names are held in the highest honour for the wonderful inventions and benefits which have been brought about. But there are two among others which, as it seems to me, the world has not yet honoured in an adequate manner. These two--Pytheas and Prince Henry the Navigator--are separated by thirteen or fourteen hundred years, but their inestimable help consisted in making the ocean less a trackless expanse than a limited space whereon the mariner was not permanently lost, but could find his position along its surface even though the land was not sighted for many a day. Think of the indirect results of this new ability. Think of the subsequent effects on the history of the world--the establishment of new trade routes consequent on the discovery of new continents, the impetus to enterprise, the peopling of new lands, the rise of young nations, the growth of sea-power, the spread of Christianity, the accumulation of fortunes and the consequent encouragement given to the arts and sciences. It is indeed a surprising but unhappy fact that humanity, because normally it has its habitation on land, forgets how much it owes to the sea for almost everything that it possesses. Perhaps this statement may be less applicable to the European continent, but it is in every sense true of all the other parts of the world.