258 SIR CHARLES LYELL. 



I am sure that six hours in bed, which is all we 

 allcrvr, and exercise all day long for the body, and 

 geology for the mind, ... is the best thing that 

 can be invented in this world for my health and 

 happiness." 



Eighteen hours of labor daily, and yet he was 

 happy ! He had found his life-work now. To a 

 sister he writes about the beetles at Aix. He can- 

 not be laughed out of this study as when a boy. 

 He has been to Parma, to see Professor Guidotti's 

 "finest collection of fossil-shells in Italy, . . . 

 spending three days, from six o'clock in the 

 morning till night, exchanging our respective 

 commodities." 



To his sisters he writes all his discoveries in 

 rocks and fossils, with the enthusiasm of a boy. 

 " I rode to the upper Val d'Arno, a famous day 

 for me, an old lacustrine deposit, corresponding 

 delightfully with our Angus lakes in all but age 

 and species of animals ; same genera of shells. 

 They have just extracted the fortieth skeleton of 

 hippopotamus ; have got about twenty elephants, 

 one or two mastodons, a rhinoceros and stags, and 

 oxen out of number. . . . At Rome I found the 

 geology of the city itself exceedingly interesting. 

 The celebrated seven hills, of which you have read, 

 and which in fact are nine, are caused by the Tiber 

 and some tributaries, which have cut open valleys 

 almost entirely through volcanic ejected matter, 

 covered by travertine containing lacustrine shells." 



He made the ascent of Etna, and sketched the 



