498 Philosophical Magazine, 4th Series, January 1870, vol. xxxix. p. 2.

499 Novum Organum, bk. ii. Aphorism 25.

500 Faraday’s Experimental Researches in Chemistry and Physics, p. 93.

501 Memorabilia, iv. 7.

502 Experimental Researches in Electricity, Series xii. vol. i. p. 420.

503 Life of Faraday, vol. ii. p. 7.

504 Nature, vol. ii. p. 278.

505 Journal of the Chemical Society, vol. viii. p. 51.

506 Correlation of Physical Forces, 3rd edit. p. 184.

507 Philosophical Magazine, 4th Series, vol. xlii. p. 451.

508 Grove, Correlation of Physical Forces, 3rd edit. p. 118.

509 Ibid. pp. 166, 199, &c.

510 Philosophical Transactions, 1861. Chemical and Physical Researches, p. 598.

511 Life of Sir W. Hamilton, p. 439.

512 Powell’s History of Natural Philosophy, p. 201. Novum Organum, bk. ii. Aphorisms 5–7.

513 Thomson and Tait, Treatise on Natural Philosophy, vol. i. pp. 346–351.

514 Philosophical Transactions (1740), vol. xli. p. 454.

515 Principia, bk. i. Law iii. Corollary 6.

516 Helmholtz, Taylor’s Scientific Memoirs (1853), vol. vi. p. 118.

517 Lucretius, bk. i. lines 232–264.

518 Novum Organum, bk. 1 Aphorism 104.

519 The Unity of Worlds and of Nature, 2nd edit. p. 116.

520 Principia, bk. iii, ad initium.

521 Keill, Introduction to Natural Philosophy, p. 89.

522 Jeremiæ Horroccii Opera Posthuma (1673), pp. 26, 27.

523 Young’s Works, vol. ii. p. 564.

524 Essay on Logic, Works, vol. viii. p. 276.

525 Life of Faraday, by Bence Jones, vol. ii. p. 206.

526 Lacroix, Traité Élémentaire de Calcul Différentiel et de Calcul Intégral, 5^me édit. p. 699.

527 Histoire des Mathématiques, vol. i. p. 298.

528 See Goodwin, Cambridge Philosophical Transactions (1845), vol. viii. p. 269. O’Brien, “On Symbolical Statics,” Philosophical Magazine, 4th Series, vol. i. pp. 491, &c. See also Professor Clerk Maxwell’s delightful Manual of Elementary Science, called Matter and Motion, published by the Society for Promoting Christian Knowledge. In this admirable little work some of the most advanced results of mechanical and physical science are explained according to the method of quaternions, but with hardly any use of algebraic symbols.

529 Birch, History of the Royal Society, vol. iii. p. 262, quoted by Young, Works, vol. i. p. 246.

530 Opticks, Query 28, 3rd edit. p. 337.

531 Rankine, Philosophical Transactions (1856), vol. cxlvi. p. 282.

532 Cosmotheoros (1699), p. 16.

533 Laplace, System of the World, vol. ii. p. 316.

534 Cosmotheoros (1699), p. 17.

535 Ibid. p. 36.

536 System of the World, vol. ii. p. 326. Essai Philosophique, p. 87.

537 Principia, bk. ii. Section ii. Prop. x.

538 De Morgan, Cambridge Philosophical Transactions, vol. xi. Part ii. p. 246.

539 Life of Faraday, vol. i. p. 216.

540 Babbage, The Exposition of 1851, p. 1.

541 Daubeny’s Atomic Theory, p. 76.

542 Bakerian Lecture, Philosophical Transactions (1868), vol. clviii. p. 2.

543 Principia, bk. ii. Prop. 20. Corollaries, 5 and 6.

544 Treatise on Natural Philosophy, vol. i. p. 50.

545 Maxwell’s Theory of Heat, (1871), p. 175.

546 Galton, on the Height and Weight of Boys. Journal of the Anthropological Institute, 1875, p. 174.

547 Grant’s History of Physical Astronomy, p. 116.

548 Discourse to the Royal Society, 28th May, 1684.

549 Robert Hooke’s Posthumous Works, p. 365.

550 Experimental Researches in Electricity, vol. ii. pp. 240–245.

551 Murchison’s Silurian System, vol. ii. p. 733, &c.

552 Philosophical Transactions (1872), vol. clxii. No. 23.

553 Philosophical Transactions (1852), vol. cxlii. pp. 465, 548, &c.

554 Philosophical Magazine, 4th Series, vol. i. p. 182.

555 Maxwell, Theory of Heat, p. 123.

556 Prior Analytics, ii. 2, 8, and elsewhere.

557 Hofmann’s Introduction to Chemistry, p. 198.

558 Stewart’s Elementary Treatise on Heat, p. 80.

559 Jevons, Proceedings of the Manchester Literary and Philosophical Society, 6th March, 1877, vol. xvi. p. 164. See also Mr. W. E. A. Axon’s note on the same subject, ibid. p. 166.

560 A Treatise on Logic, or, the Laws of Pure Thought, by Francis Bowen, Professor of Moral Philosophy in Harvard College, Cambridge, United States, 1866, p. 315.

561 Proceedings of the Royal Society, November, 1873, vol. xxi. p. 512.

562 Lectures on the Elements of Comparative Anatomy, 1864, p. 1.

563 Essai sur la Philosophie des Sciences, p. 9.

564 Lectures on the Elements of Comparative Anatomy, and on the Classification of Animals, 1864, p. 3.

565 Ossemens Fossiles, 4th edit. vol. i. p. 164. Quoted by Huxley, Lectures, &c., p. 5.

566 Chambers, Descriptive Astronomy, 1st edit. p. 23.

567 Philosophical Magazine, 4th Series, vol. xxxix. p. 396; vol. xl. p. 183; vol. xli. p. 44. See also Proctor, Popular Science Review, October 1874, p. 350.

568 Humboldt, Cosmos (Bohn), vol. iii. p. 224.

569 Baily, British Association Catalogue, p. 48.

570 Outlines of Astronomy, § 850, 4th edit. p. 578.

571 Life of Faraday, vol. ii. p. 87.

572 Proceedings of the Royal Society, vol. xvii. p. 212. Chemical and Physical Researches, reprint, by Young and Angus Smith, p. 290.

573 Essai sur la Nomenclature et la Classification, Paris, 1823, pp. 107, 108.

574 George Bentham, Outline of a New System of Logic, p. 115.

575 Outline of a New System of Logic, 1827, p. 117.

576 Porphyrii Isagoge, Caput ii. 24.

577 Jevons, Elementary Lessons in Logic, p. 104.

578 Chrestomathia; being a Collection of Papers, &c. London, 1816, Appendix V.

579 The Classification of the Sciences, &c., 3rd edit. p. 7. Essays: Scientific, Political, and Speculative, vol. iii. p. 13.

580 Owen, Essay on the Classification and Geographical Distribution of the Mammalia, p. 20.

581 Dana’s Mineralogy, vol. i. p. 123; quoted in Watts’ Dictionary of Chemistry, vol. ii. p. 166.

582 Instructions for the Discrimination of Minerals by Simple Chemical Experiments, by Franz von Kobell, translated from the German by R. C. Campbell. Glasgow, 1841.

583 Edition of 1866, p. lxiii.

584 Philosophia Botanica (1770), § 154, p. 98.

585 Philosophical Magazine, 3rd Series (1845), vol. xxvi. p. 522. See also De Morgan’s evidence before the Royal Commission on the British Museum in 1849, Report (1850), Questions, 5704*-5815*, 6481–6513. This evidence should be studied by every person who wishes to understand the elements of Bibliography.

586 English Cyclopædia, Arts and Sciences, vol. v. p. 233.

587 Swainson, “Treatise on the Geography and Classification of Animals,” Cabinet Cyclopædia, p. 201.

588 Darwin, Fertilisation of Orchids, p. 159.

589 Descent of Man, vol. i. p. 214.

590 Laws of Botanical Nomenclature, p. 16.

591 Waterhouse, quoted by Woodward in his Rudimentary Treatise of Recent and Fossil Shells, p. 61.

592 Bentham’s Handbook of the British Flora (1866), p. 25.

593 Philosophia Botanica (1770), § 157, p. 99.

594 Ibid. § 159, p. 100.

595 Amœnitates Academicæ (1744), vol. i. p. 70. Quoted in Edinburgh Review, October 1868, vol. cxxviii. pp. 416, 417.

596 Descent of Man, vol. i. p. 228.

597 Agassiz, Essay on Classification, p. 219.

598 Ibid. p. 249.

599 Philosophia Botanica, § 155, p. 98.

600 Laws of Botanical Nomenclature, by Alphonse Decandolle, translated from the French, 1868, p. 19.

601 Darwin, The Variation of Animals and Plants, vol. ii. pp. 293, 359, &c.; quoting Paget, Lectures on Pathology, 1853, pp. 152, 164.

602 Ibid. vol. ii. p. 372.

603 Théorie Analytique des Probabilités, quoted by Babbage, Ninth Bridgewater Treatise, p. 173.

604 First Bridgewater Treatise (1834), pp. 16–24.

605 System of Logic, 5th edit. bk. III. chap. V. § 7; chap. XVI. § 3.

606 System of Logic, vol. i. p. 384.

607 Ninth Bridgewater Treatise, p. 140.

608 Ibid. pp. 34–43.

609 Professor Clifford, in his most interesting lecture on “The First and Last Catastrophe” (Fortnightly Review, April 1875, p. 480, reprint by the Sunday Lecture Society, p. 24), objects that I have erroneously substituted “known laws of nature” for “known laws of conduction of heat.” I quite admit the error, without admitting all the conclusions which Professor Clifford proceeds to draw; but I maintain the paragraph unchanged, in order that it may be discussed in the Preface.

610 Tait’s Thermodynamics, p. 38. Cambridge Mathematical Journal, vol. iii. p. 174.

611 Clerk Maxwell’s Theory of Heat, p. 245.

612 Maxwell’s Theory of Heat, p. 92.

613 Report of the British Association (1852), Report of Sections, p. 12.

614 Mr. C. J. Monroe objects that in this statement I do injustice to Comte, who, he thinks, did impress upon his readers the inadequacy of our mental powers compared with the vastness of the subject matter of science. The error of Comte, he holds, was in maintaining that science had been carried about as far as it is worth while to carry it, which is a different matter. In either case, Comte’s position is so untenable that I am content to leave the question undecided.

615 Fragments of Science, p. 362.

616 Familiar Lectures on Scientific Subjects, p. 458.

617 Philosophical Magazine, 3rd Series, vol. xxvi. p. 406.

618 History of the Theory of Probability, p. 398.

619 Trigonometry and Double Algebra, chap. ix.

620 Agassiz, Essay on Classification, p. 75.