vi PHYSICAL SCIENCE 



upon the subject of physical speculation. Its 

 currency during the Middle Ages rendered it for 

 many centuries the chief authority in science in 

 Western Europe. Its cosmology represented not 

 only popular but also educated opinion, and became 

 the source of many of the accepted ideas concerning 

 the universe that passed into early modern litera 

 ture in our own and other countries. 



Indebtedness to editors of Seneca and to others, 

 which has been very great, is acknowledged as 

 fully as possible in the Introduction and elsewhere 

 where help has been availed of. The interest 

 taken in the book by various friends is also grate 

 fully acknowledged. Professor Sir Joseph Larmor 

 and Professor J. Arthur Thomson have made 

 several useful suggestions. Professor Herbert 

 J. C. Grierson has very kindly read the proofs and 

 given valuable assistance in other respects. But 

 my chief acknowledgments are due to Sir Archibald 

 Geikie. To him the translation owed its inception : 

 his constant aid and encouragement have enabled 

 me to complete a task from which I should probably 

 have otherwise shrunk. I am indebted to him also 

 for the Commentary appended to the translation, 

 in which the questions treated by Seneca are con 

 sidered from the point of view of modern Science. 

 It has been to him a labour of love : may our 

 readers enjoy something of the, same satisfaction ! 



J. C. 



OLD ABERDEEN, 



September 27, 1909. 



