_Bolyai’s Science Absolute of Space (Austin, 1896), Introduction, p. 18._ =927.= [Wolfgang Bolyai] was extremely modest. No monument, said he, should stand over his grave, only an apple-tree, in memory of the three apples: the two of Eve and Paris, which made hell out of earth, and that of Newton, which elevated the earth again into the circle of the heavenly bodies.--CAJORI, F. _History of Elementary Mathematics (New York, 1910), p. 273._ =928.= Bernard Bolzano dispelled the clouds that throughout all the foregone centuries had enveloped the notion of Infinitude in darkness, completely sheared the great term of its vagueness without shearing it of its strength, and thus rendered it forever available for the purposes of logical discourse.--KEYSER, C. J. _Lectures on Science, Philosophy and Art (New York, 1908), p. 42._ =929.= Let me tell you how at one time the famous mathematician _Euclid_ became a physician. It was during a vacation, which I spent in Prague as I most always did, when I was attacked by an illness never before experienced, which manifested itself in chilliness and painful weariness of the whole body. In order to ease my condition I took up _Euclid’s Elements_ and read for the first time his doctrine of _ratio_, which I found treated there in a manner entirely new to me. The ingenuity displayed in Euclid’s presentation filled me with such vivid pleasure, that forthwith I felt as well as ever.--BOLZANO, BERNARD. _Selbstbiographie (Wien, 1875), p. 20._ =930.= Mr. Cayley, of whom it may be so truly said, whether the matter he takes in hand be great or small, “_nihil tetigit quod non ornavit_,”....--SYLVESTER, J. J. _Philosophic Transactions of the Royal Society, Vol. 17 (1864), p. 605._ =931.= It is not _Cayley’s_ way to analyze concepts into their ultimate elements.... But he is master of the _empirical_ utilization of the material: in the way he combines it to form a single abstract concept which he generalizes and then subjects to computative tests, in the way the newly acquired data are made to yield at a single stroke the general comprehensive idea to the subsequent numerical verification of which years of labor are devoted. _Cayley_ is thus the _natural philosopher_ among mathematicians.--NOETHER, M. _Mathematische Annalen, Bd. 46 (1895), p. 479._ =932.= When Cayley had reached his most advanced generalizations he proceeded to establish them directly by some method or other, though he seldom gave the clue by which they had first been obtained: a proceeding which does not tend to make his papers easy reading....