^iS Prof. De Morgan 07i the Additions made to the 



noting the fact, can I do less than enter a protest. I must 

 notice the fact, because, with reference to the paper decently 

 interred at Somerset House, bnt exhumable at pleasure of any 

 Fellow of the Society, it is necessary that I should announce 

 that the present communication is altogether rewritten, with- 

 out my even* seeing the former one. 



It is obvious that, iVom the moment when the fact of inter- 

 polation is known, the second edition can be no longer cited. 

 But as the scarcity of the first (of which only a few copies 

 were printed, and those all distributed as presents, — it was 

 very scarce even in 1715) makes the citation of it almost im- 

 possible, the remedy is to publish a full account of all the 

 variations. This I do, excepting of course alterations of re- 

 ference, and excepting also trifling changes of idiom, to mend 

 the Latin, such as altering an indicative into a subjunctive, and 

 the like. 



The first editionf was published in 1712. Leibnitz died 

 in 1716. The second edition exists with two J title pages, 

 one of 1722, the other of 1725, but both from the same type. 

 Something which cannot now be explained occurred in the 

 printing. Sheet K ends with page 14'4, but L begins with a 

 second page 129; and this wrong paging is continued to the 

 end of M, after which N begins with 177, as it would have 

 done if there had been no interruption. In i\\e Ad Lectorem, 

 page 169 is referred to, which does not exist: that which 

 should have been 169 is the second 153, and there the matter 

 is found to which reference was made. 



* I am quite aware that the Society would have allowed me to copy it, 

 if I had been so inclined. 



"t" Its title is " Coninierciiim Epistolicuni D. Johannis Collins, et aliorum 

 de Analysi promcta : jiissu Societatis Regire In lucem edit inn. Londini : 

 typisPearsonianis.Anno MDCC XII." Qiiarto(folio signatures), pp. iv+ 122. 



X The first has after the word edilum, " Et jam Una cum ejusdem Recen- 

 sionc praeniissa, et Judicio ];rimarii, ut fcrebatur, Matheniatici subjiincto, 

 iteiuai impressum. Londini : E.k Officina et inipensis J. Tonson, et J. 

 Watts, prostant venales apud Jacobum Mack-Euen, Bibliopolam Edinbur- 

 genseni. M DCC XXII." Octavo, pp. vi + 250+i (errata). 



The second is " Commerciuni Epistolicuni de Varia Re Mathematica, 

 Inter Celeberrimos praesentis seculi Mathematicos. Yiz. Isaacum New- 

 tonnm Equitem Auratuni. Dnum Isaacum Barrow. Dnum Jacobum Grc- 

 gorium. Dnum .lohanneni Wallisium. Dnum J. Keilliuni. DnumJ. Colli- 

 niuni. Dnum Gulielmum Leibnitium. Dnum llenricum Oldenbourgum. 

 Dnum Franciscum Siusium. Et alios. Jussu Societatis Regias in hicem 

 editnm. El jam Una cum Recensione pracmissa insignia Controver.siae inter 

 Leibnitium et Keillimn de primo Inventore Metiiodi Fluxionum ; et Judicio 

 primarii, ut ferebatur, Mathematici snbjnncto, iterum imprcssun). Lon- 

 dini : Impensis J. Tonson et J. Watts, Prostant venales apud J. Mac Euen 

 ad Insigne Georgii Bnciianani e regione templi Sancti Clementis in vico 

 vuigo dicto the Strand. I7~5." Octavo, &€., as before. 



