272 PETER GUTHRIE TAIT 



It may be, however, that this apparent inconsistency is in reality dictated by skill 

 and prudence. The suspicious reader, already put on his guard by Clerk Maxwell's 

 first cautious introduction of the evil thing, has to be treated with anxious care and 

 nicety of handling : lest he should refuse altogether to bite again. If he rises to the 

 present cast we shall probably find that Prof. Clifford has V, in the form as it were of a 

 gaff, ready to fix him irrevocably. That he will profit by the process, in the long run, 

 admits of no doubt : so the sooner he is operated on the better. What is now urgently 

 wanted, for the progress of some of the most important branches of mathematical 

 physics, is a " coming " race of intelligent students brought up, as it were, at the feet of 

 Hamilton ; and with as little as may be of their freshness wasted on the artificialities 

 of x, y, z. Till this is procured, quaternions cannot have fair play. Nut-cracking, 

 though occasionally successful for a moment, is the most wasteful and destructive 

 of all methods of sharpening the teeth. 



What we have at some length discussed is the most prominent feature of the 

 present work, but by no means its only distinctive one. No writer, who has any claim 

 upon his readers at all, can treat even the most hackneyed subject without giving 

 a new and useful turn to many a long-known truth. Many of Prof. Clifford's proofs 

 are exceedingly neat, and several useful novelties (e.g. Three-bar Motion) are introduced. 

 We have to complain, however, of a great deal of unnecessary new and very strange 

 nomenclature : for a large part of which the author is not responsible, his error 

 (for such we cannot help considering it) consisting in giving this stuff a place of 

 honour in his book. One does not require to be very violently conservative to 

 feel dismayed at an apparently endless array of such new-fangled terms as Pedals, 

 Rotors, Cylindroids, Centrodes, Kites, Whirls, and Squirts ! Yet these are but a 

 few gleaned at random from the book. Something, it seems, must be hard in a 

 text-book simplify the Mathematic, and the Anglic (i.e. the English) immediately 

 becomes perplexing. 



In Nature of June u, 1885 (Vol. xxxn), Tait reviewed Clifford's 

 The Common Sense of the Exact Sciences, a book which was published 

 six years after the author's death. The following sentences seem of sufficient 

 permanent interest to deserve quotation : 



Once more a characteristic record of the work of a most remarkable, but too brief, 

 life lies before us. In rapidity of accurate thinking, even on abstruse matters, Clifford 

 had few equals ; in clearness of exposition, on subjects which suited the peculiar bent 

 of his genius and on which he could be persuaded to bestow sufficient attention, still 

 fewer. But the ease with which he mastered the more prominent features of a subject 

 often led him to dispense with important steps which had been taken by some of his 

 less agile concurrents. These steps, however, he was obliged to take when he was 

 engaged in exposition ; and he consequently gave them (of course in perfect good 

 faith) without indicating that they were not his own. Thus, especially in matters 

 connected with the development of recent mathematical and kinematical methods, 

 his statements were by no means satisfactory (from the historical point of view) to 



