170 Mary Somerville. 



scrape we may get into. Laplace, page 20, Mec. Cel. art. 

 7, is a little obscure here, and in deriving his equation 

 (/) a page of explanation would be well bestowed. 



One thing let me recommend, if you use as principles 

 either this, or that of virtual velocities, or any other, state 



them broadly and in general terms 



You will think me, I fear, a rough critic, but I think of 

 Horace's good critic, 



Fiet Aristarchus : nee dicet, cur ego amicum 

 Offendam in nugis ? Hae nugae seria ducent 

 In mala, 



and what we can both now laugh at, and you may, if you 

 like, burn as nonsense (I mean these remarks), would come 

 with a very different kind of force from some sneering 

 reviewer in the plenitude of his triumph at the detection 

 of a slip of the pen or one of those little inaccuracies 



which humana parum cavit natura 



Very faithfully yours, 



J. HERSCHEL. 



[About the same time my father received a letter from 

 Dr. Whewell, afterwards Master of Trinity College, 

 Cambridge, dated 2nd November, 1831, in which he 

 says : 



" I beg you to offer my best thanks to Mrs. Somerville 

 for her kind present. I shall have peculiar satisfaction 

 in possessing it as a gift of the author, a book which I 

 look upon as one of the most remarkable which our age 

 has produced, which would be highly valuable from any- 

 one, and which derives a peculiar interest from its writer. 



