Another instance of computation carried to paradoxical length, in order to illustrate a method, is the solution of x^3 - 2x = 5, the example given of Newton's method, on which all improvements have been tested. In 1831, Fourier's[142] posthumous work on equations showed 33 figures of solution, got with enormous labor. Thinking this a good opportunity to illustrate the superiority of the method of W. G. Horner,[143] not yet known in France, and not much known in {67} England, I proposed to one of my classes, in 1841, to beat Fourier on this point, as a Christmas exercise. I received several answers, agreeing with each other, to 50 places of decimals. In 1848, I repeated the proposal, requesting that 50 places might be exceeded: I obtained answers of 75, 65, 63, 58, 57, and 52 places. But one answer, by Mr. W. Harris Johnston,[144] of Dundalk, and of the Excise Office, went to 101 decimal places. To test the accuracy of this, I requested Mr. Johnston to undertake another equation, connected with the former one in a way which I did not explain. His solution verified the former one, but he was unable to see the connection, even when his result was obtained. My reader may be as much at a loss: the two solutions are: 2.0945514815423265... 9.0544851845767340... The results are published in the _Mathematician_, Vol. III, p. 290. In 1851, another pupil of mine, Mr. J. Power Hicks,[145] carried the result to 152 decimal places, without knowing what Mr. Johnston had done. The result is in the _English Cyclopaedia_, article INVOLUTION AND EVOLUTION. I remark that when I write the initial of a Christian name, the most usual name of that initial is understood. I never saw the name of W. G. Horner written at length, until I applied to a relative of his, who told me that he was, as I supposed, Wm. _George_, but that he was named after a relative of that _surname_. The square root of 2, to 110 decimal places, was given {68} me in 1852 by my pupil, Mr. William Henry Colvill, now (1867) Civil Surgeon at Baghdad. It was 1.4142135623730950488016887242096980785696 7187537694807317667973799073247846210703 885038753432764157273501384623 Mr. James Steel[146] of Birkenhead verified this by actual multiplication, and produced 2 - 2580413 / 10^{117} as the square. Calcolo decidozzinale del Barone Silvio Ferrari. Turin, 1854, 4to. This is a serious proposal to alter our numeral system and to count by twelves. Thus 10 would be twelve, 11 thirteen, etc., two new symbols being invented for ten and eleven. The names of numbers must of course be changed. There are persons who think such changes practicable. I thought this proposal absurd when I first saw it, and I think so still:[147] but the one I shall presently describe beats it so completely in that point, that I have not a smile left for this one. ON COMETS. The successful and therefore probably true theory of Comets. London, 1854. (4pp. duodecimo.)