16 NOVEMBER 1872, Page 3

The Atheneum of last week, being ambitious to correct an

error which we had not made, fell into error itself, in the following slipshod statement :—" In last week's Spectator it is assumed that 'Dc Morgan's Probabilities' was by De Morgan. Natural as this seems, a correspondent assures us that Professor De Morgan once informed him that his name was attached to the work in mistake. Every Cambridge man knows that there is at least a doubt upon the point." The Atheneum's correspondent was confusing two quite distinct matters, and the Atheneum itself answered very rashly for "every Cambridge man," who is not quite so ill- informed on the subject as is assumed. What we referred to (p. 1398 of our number of this day fortnight) was De Morgan's "Essay on Probabilities," written chiefly with a view to elucidate popularly the principle of Life Insurance. No one ever thought of attributing either this, or his more learned mathematical essay republished from the Encyclopaedia Met ropolitana, to anyone but De Morgan. Indeed, be constantly referred to both as his own in his lec- tures. The Athenmum's correspondent was thinking of the late Sir John Lubbock's '1 Useful Knowledge" tract on Probability, pre- pared by him jointly with Mr. Drink water Bethune, on the outer cover of which Mr. De Morgan's name did appear by mistake,—the mistake being recounted and corrected, in the very "Budget of Paradoxes" we were reviewing, in a most amusing passage, wherein Mr. De Morgan quizzes his old friend Sir J. Lubbock for his pre- cision of style,—for preferring, for instance, the word 'probability' in the singular for 'probabilities' in the plural, and for writing 'obverse and reverse' instead of head and tail.' On this Mr. De Morgan remarks that Sir J. Lubbock could not, however, keep up this precision, for having to mention the winner of a race, Beau Bedlam' by name, he did not write, as he ought to have done, Elizabeth Bethlehem,' but followed the jockeys. The Atheneum and its correspondent have found a maresnest.