Second Edition of the Commercium Epistolicum. 451 



guntur in Lib. Epist. Regise Parisiis Jul. 15et Oct. 36[sic] 

 Societatis N°. 7. pag. 93 et datas, quae leguntur in Lib. 

 110, eaedemque reperiuntur Epist. Regiee Societatis N° 7. 

 impressae in Tomo tertioOpe- pag. 93 et 110, eaedemque re- 

 rum Mathematicorum D. J. periuntur impressae in Tomo 

 Wallis. tertio Operum Matliematico- 



rum D. J. Wallis, et in scri- 

 niisReg. Societatis asservantur 

 earum Autographa. 



It is particularly to be noted, that the additions make it 

 appear that new access had been obtained to the stores of the 

 Royal Society ; and this shows, on the one hand, that the 

 new edition* came from the Society, and on the other, that 

 there is pro tanto evidence for the facts slated. The new 

 editors have prefixed to the extract from the letter of July 15 

 the first words of the letter, " Diu est quod nuUas a me ha- 

 buisti literas." 



With regard to the assertion about Leibnitz, first made 

 after his death, that up to 1673 he had concerned himself with 

 arithmetic only, and from that time applied himself to geometry, 

 it is founded upon his having first corresponded on arithmetic 

 and afterwards on geometry. It was intended to prejudice 

 his cause, by producing the impression that at the time of his 

 announcement of the differential Calculus he was but a new 

 student of the higher analysis. With the statement, however, 

 I have nothing to do here, except to note the unfaii'ness of 

 printing it as if he had been challenged to deny it during his 

 life, and had not done so. Remembering how nearly the life 

 of Leibnitz was absorbed in jurisprudence, politics, history and 

 metaphysics, and how little of it remained for mathematics, — 

 remembering also the uniform manner in which Leibnitz's 

 later declarations of this press of occupation were treated as 

 evasion, — it would have been fairer if one of the earlier decla- 

 rations, made before any question arose, had been inserted by 

 the original editors from the first of these two letters, " In- 

 cumbunt enim mihi labores quidem inter se plane diversi; 

 quos partim Principes a me exigunt, partim Amici. Unde 

 parum temporis restat quod inquisitioni Naturae, et contem- 

 plationibus Malhematicis impendere possim." 



• This, I believe, was never doubted, though the names of the editors 

 have never been published that I know of. Another fact is, that the dia- 

 grams of the second edition are from tiie same wood-blocks as those of the 

 first, which certainly were the |)ro|)erty of the Society. Biot attributes the 

 publication to Newton himself, of which there is no proof Newton may 

 nave suggested or approved a second edition ; but that he should take any 

 part in its preparation, at the ago of eighty-two, is very unlikely. 



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