163 Mary Somerville. 



herself. This great philosopher was my mother's truest 

 and best friend, one whose opinion she valued above all 

 others, whose genius and consummate talents she ad- 

 mired, and whose beautiful character she loved with an 

 intensity which is better shown by some extracts from 

 her letters to be given presently than by anything I can 

 say. This deep regard on her part he returned with the 

 most chivalrous respect and admiration. In any doubt 

 or difficulty it was his advice she sought, his criticism 

 she submitted to ; both were always frankly given with- 

 out tl.e slightest fear of giving offence, for Sir John 

 Herschel well knew the spirit with which any remarks of 

 his would be received. 



FROM SIR JOHN HERSCHEL TO MRS. SOMERVILLE. 



SLOUGH, Feb. 23rd, 1830. 

 MY DEAR MRS. SOMERVILLE, 



As you contemplate separate 



publication, and as the attention of marry will be turned 

 to a work from your pen who will just possess quantum 

 enough of mathematical knowledge to be able to read the 

 first chapter without being able to follow you into its 

 application, and as these, moreover, are the very people 

 who will think themselves privileged to criticise and use 

 their privilege with the least discretion, I cannot recom- 

 mend too much clearness, fulness, and order in the 

 expose of the principles. Were I you, I would devote to 

 this first part at least double the space you have done. 

 Your familiarity with the results and formula has led you 

 into what is extremely natural in such a case a somewhat 

 hasty passing over what, to a beginner, would prove 



