Second Edition of the Commerciiun Epistoliciim. 449 



With the new Ad Lcctorem, the liecensio taken from the 

 Philosophical Transactions, the reprint of John Bernoulli's 

 letter and the comments on it, I have nothing to do; this is 

 all avowedly new matter. The reprint commences with the 

 old title-page, the words typis Pearsonianis being omitted. 

 The variations areas follows: the first paging being that of 

 the first edition, the second of the second. 



I. (12, 80). The following note is added ; "* N.B, eodem 



sensu quo Nevotonus utitur symbolo 



aa 



Leibnitius utitur 



Symbolo S " Interpreting this note in the sense of all 



the rest, it implies of course that Leibnitz took Newton's mean- 

 ing and adapted it to a new symbol. This is not correct in 

 any particular; for Newton's symbol merely means "area to 

 the ordinate aa : 64*'," while Leibnitz's symbol means the sum 

 of diiFerentials or integral. And moreover Leibnitz does not 

 use the symbol S// but Hydx, involving a very different idea. 

 Neither is it pretended that Leibnitz, before publication of his 

 system, ever saw the letter on which this note is written, or 

 any other which contains the symbol above given. 



IL (18, 90). All the words in the note from " Eadem ex- 

 plicatur" to "Anno 1669" are new. The new editors un- 

 dertake to assert that a method, which Newton only alludes 

 to, must have been the method in the fifth proposition of the 

 book on Quadratures. That is to say, those v/ho in their 

 new Ad Lectorem, construe Leibnitz's silence as an admission 

 of everything, make him admit one proposition more. This 

 remark of course may be made throughout. 



III. (19,91). This note is new: ^^ Leibnitius scribit c?a: pro 

 o vel o.v\, dz pro ov vel oij." Another unfairness of the same 

 sort as in (I.). It is not pretended that Leibnitz ever saw 

 this letter, or any other in which x + o is written for x; but 

 under the assertion that Leibnitz saw certain letters, the new 

 editors exaggerate the prevailing fallacy of the old ones, 

 namely, the assumption of the right to bring any letters forward 

 as proving that what Leibnitz had in common with them must 

 have been takeny?o?« them. Those who remember the rational 

 protest which the English made against the editors of the 

 Leipsic Acts (January 170.')), for using words implying substi- 

 tution instead of independent adoption, when describing what 

 Newton had done, and the lame answer which was made to 

 that protest, will recognise a parallel in the conduct of both 

 sets of eilitors, new and old, of the Commercium Epistolicwn. 



IV. (2'J, 96). The note is new. Gregory states that he 

 had derived a method of tangents from that of Barrow ; on 



Phil. Mag, S. 3. Vol. 32. No. 2 1 7. June 1 848. 2 G 



