PREFACE Vll 



and laws from thoso that arc clue to the human 

 colouring in which the extraordinary event has 

 become enveloped. The inclusion of the impossible 

 has only served to throw doubt on those portions 

 of the narrative which are possible. Even with 

 the omission of the former, there is much that is 

 difficult to explain and which requires further re- 

 search. I am however encouraged, as the hypothesis 

 satisfies so many of the conditions of the problem, 

 to hope for a solution favourable to the inter- 

 pretation herein suggested. Much more time ar.-d- 

 many more workers are however required for the 

 investigation of the many questions involved in 

 the inquiry. 



In any case, if the connection of the Tradition with 

 the phenomena dcscrcd in these pages fails to find 

 confirmation, their study from a geological point of 

 view nr-y, I trust, be advanced by the collocation of 

 the facts which I have grouped together under the 

 designation of the "Bubble-drift." 



As the subject is necessarily technical, I have 

 given only such few geological details as are needed 

 for the argument, in a i> anner I trust to : under- 

 stood by those who have but a slight acquaintance 

 with that science. Geologists will find the fuller 

 details and discussion of the facts in the several 

 papers referred to in the text. 



JOSEPH PEESTWICH. 



