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painted for their hall. An inquiry was then made of all the members of his family; but no portrait of any description could be found. I have heard my father say that Gilbert White was much pressed by his brother Thomas (my grandfather) to have his portrait painted, and that he talked of it; but it was never done. A. HOLT WHITE. _"A Tub to the Whale"_ (Vol. viii., p. 220.).--In the Appendix B. to Sir James Macintosh's _Life of Sir Thomas More_ is the following passage: "The learned Mr. Douce has informed a friend of mine, that in Sebastian Munster's _Cosmography_ there is a cut of a ship, to which a whale was coming too close for her safety; and of the sailors throwing a tub {305} to the whale, evidently to play with. The practice of throwing a tub or barrel to a large fish, to divert the animal from gambols dangerous to a vessel, is also mentioned in an old prose translation of the _Ship of Fools_. These passages satisfactorily explain the common phrase of throwing a tub to a whale." Sir James Macintosh conjectures that the phrase "the tale of a tub" (which was familiarly known in Sir Thomas More's time) had reference to the tub thrown to the whale. C. H. COOPER. Cambridge. _The Number Nine_ (Vol. viii., p. 149.).--The property of numbers enunciated and illustrated by MR. LAMMENS resolves itself into two. 1. If from any number above nine be subtracted the number expressed by writing the same digits backwards, the remainder is divisible by nine. 2. If the number nine measure a given number, it measures the sum of its digits. As the latter is proved in most elementary books on Algebra, I confine my proof to the former. Let the number in question be-- _a__0 + _a__1 . 10 + _a__2 . 10^2 + ... + _a__{_n_-1} . 10^{_n_-1} + _a__{_n_} . 10^{_n_} Then _a__{_n_} + _a__{_n_-1} . 10 + _a__{_n_-2} . 10^2 + ... + _a__1 . 10^{_n_-1} + _a__0 . 10^{_n_} is "the same number written backwards." The difference is-- (_a__{_n_} - _a__0)(10^{_n_} - 1) + (_a__{_n_-1} - _a__1)(10^{_n_-2} - 1) . 10 + ... + (_a__{_n_/2+1} - _a__{_n_/2-1})(10^2-1) . 10^{_n_/2-1} if _n_ be even, but + (_a__{(_n_+1)/2} - _a__{(_n_-1)/2})(10-1) . 10^{(n-1)/2} if _n_ be odd. And every term of this difference, as involving a factor of the form (1 - 10^{_n_}), is divisible by 9; and therefore the difference is divisible by 9. C. MANSFIELD I
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