A PAETING WORD. 



N completing this long work, begun in the clays of my youth, I 

 may congratulate myself on the good fortune by which, in the 

 course of a life not lacking in stirring incidents, I have been 

 enabled to fulfil my engagements of regular publication, without 

 ever once breaking faith with my readers. At the same time I am well aware 

 that the best intentions and most conscientious labour would have been inade- 

 quate to such an undertaking, but for the devoted fellow- workers who have 

 constantly aided me by their researches and advice. 



A feeling of gratitude must therefore be uppermost, and my thanks are 

 accordingly given to all friends who have directly or indirectly helped me by 

 notes, studies, correspondence, corrections, encouragement, or criticism. But this 

 acknowledgment can no longer reach all those to whom it is due ! A retrospective 

 glance shows the path marked at intervals b}^ the memory of comrades in work 

 garnered by death. Towards them above all m}" thoughts are turned at the close 

 of my task. On this last pnge I record the name of Emile Templier, who sought 

 me out on the pontoons of Brest with a view to the publication of the long con- 

 templated Earth and its In/uibitaiits. 



This period of twenty years, long relatively to the life of a man, is as nought 

 in the history of the Earth ; yet how well it has been utilised ! IIow many 

 discoveries and explorations have followed one on the other, adding to our previous 



