18G DE MOIYRE. 



difficult to name one who has conferred more honour on his 

 adopted country than De Moivre. 



234?. Number 329 of the Philosophical Transactions consists 

 entirely of a memoir entitled De Mensura Soi^tis, sen, de Probabili- 

 tate Eventuum in Ludis a Casu Fortuito Pendentihus. Autore 

 Abr. De Moivre, RS.S. 



The number is stated to be for the months of January, 

 February, and March 1711 ; it occupies pages 213 — 261? of Vo- 

 lume XXVII. of the Philosophical Transactions. 



The memoir was afterwards expanded by De Moivre into his 

 work entitled The Doctrine of Chances: or, a Method of Calculating 

 the Pi'ohabilities of Events in Play. The first edition of this work 

 appeared in 1718 ; it is in quarto and contains xiv + 175 pages, 

 besides the title-leaf and a dedication. The second edition appeared 

 in 1738 ; it is in large quarto, and contains xiv + 258 pages, 

 besides the title-leaf and a dedication and a page of corrections. 

 The third edition appeared in 1756, after the author's death ; it is 

 in large quarto, and contains xii + 348 pages, besides the title-leaf 

 and a dedication. 



235. I propose to give an account of the memoir De Mensura 

 Sortis, and of the third edition of the Doctrine of Chances. In my 

 account of the memoir I shall indicate the corresponding parts of 

 the Doctrine of Chances ; and in my account of the Doctrine of 

 Chances I shall give such remarks as may be suggested by compar- 

 ing the third edition of the work with those which preceded it ; 

 any reference to the Doctrine of Chances must be taken to apply to 

 the third edition, unless the contrary is stated. 



236. It may be observed that the memoir De Mensura, Sortis 

 is not reprinted in the abridgement of the Philosophical Transac- 

 tions up to the year 1800, which was edited by Hutton, Shaw, and 

 Pearson. 



The memoir is dedicated to Francis Robartes, at whose recom- 

 mendation it had been drawn up. The only works of any import- 

 ance at this epoch, which had appeared on the subject, were the 

 treatise by Huygens, and the first edition of Montmort's book. 

 De Moivre refers to these in words which we have already quoted 

 in Art. 142. 



