“He had an almost miraculous power of seeing, as it were, intuitively, what factors would divide any large number, not a prime. Thus, if he were given the number 17,861, he would instantly remark that it was 327 × 53. He could not, he said, explain how he did this; it seemed a natural instinct with him.” Another expert calculator, an English civil engineer named Blyth, says in a letter: “I am conscious of an intuitive recognition of the relations of figures. For instance, in reading statements of figures in newspapers, which are often egregiously wrong, it seems to come to me intuitively that something is wrong, and when that occurs I am usually right.” In the case of at least one lightning calculator there is proof positive of the concurrent operation of two trains of thought, the one conscious, the other subconscious. This is Jedediah Buxton, who “would talk freely while doing his questions, that being no molestation or hindrance to him.” Moreover, prodigious memory power is nearly always characteristic of the lightning calculator. This of itself is evidence of unusual access to the subconscious, since it is in the subconscious that memories are stored. Most impressive of all, however, is the rapid, almost instantaneous emergence of the answers to the problems propounded by those testing the calculator’s powers. It is as though the mere putting of the problem, and the mere desire to solve it, were enough to set in motion a “thinking machine” that automatically brought about the desired result. It is significant that in most cases, as in Bidder’s, the calculators themselves are unable to give any satisfactory account of the methods they employ, and sometimes frankly admit that they “do not know how the answers come.” Now, this sudden irruption of ideas, this dazzling solution of problems, is characteristic not only of calculating prodigies, but also of all men of genius. They may not have—in truth, they have comparatively seldom—such a spectacular resort to the subconscious; but they assuredly have it in an astonishing measure, and to better purpose. Precisely as we find the answers to mathematical puzzles rising spontaneously in the minds of ready reckoners, so, time and again, do we find great thoughts, amounting it may be to epoch-making conceptions, forcing themselves upon men of genius, frequently at moments when they are consciously thinking of some other matter, or are not consciously exercising their minds at all. And again we have only to go to the published testimony of men of genius themselves to obtain a strong body of evidence bearing out this statement.