Problems of Life and Mind. Second series by George Henry Lewes (chrysanthemum read aloud txt) đ
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17 At the time this was written, I had some fish ova in the course of development. Out of the same mass, and in the same vessel, all those which were supported by weed at a depth of half an inch from the surface, lived and developed; all those, without exception, that were at a depth of two to four inches, perished. In ordinary parlance, surely, nothing would be objected to in the phrase, âthese ova were all in the same Mediumâ; the water was the same, the weed the same, the vessel the same; yet some difference of temperature and carbonic acid made all the difference between life and death. Another curious fact was observed; I removed eight of these ova with active embryos, and placed them in a large watch-glass containing a solution (one half per cent) of bichromate of ammonia. In this acid the embryos lived and were active fifty-seven hours, although other embryos placed in a similar watch-glass containing pond-water, survived only forty hours. The non-effect of the acid was probably due to the non-absorption which nullifies the effect of certain virulent poisons when they are swallowed; but why the fish should live longer in the acid than in the simple water, I do not at all comprehend.
18 Agassiz, Essay on Classification, 1859, p. 15.
19 Haeckel, Generelle Morphologie, II. 211.
20 See on this last point Ranke, Die Lebensbedingungen der Nerven, 1868, p. 34.
21 See Waldeyer, art. Eierstock, in Strickerâs Handbuch der Lehre von den Geweben, 1870, p. 570. âI found in a fĆtus, which, in a case of extra-uterine pregnancy, had lain thirty years in the body of its mother, the structure of the muscles as intact as if it had been born at its full time.ââVirchow, Cellular Pathologie, Lect. XIV.
22 See Beale, The Structure of the Simple Tissues, 1861; the Introd. to his edition of Todd and Bowmanâs Physiological Anatomy, 1866; and How to Work with the Microscope, 4th ed., 1868; also Bioplasm, 1872.
23 âThe physical property of the tissue does not depend upon this matter, nor is its function due to it.ââBeale, Introduction to Todd and Bowman, p. 11. That is to say, he regards even contractility and neurility as physical, not vital facts.
24 In turning over the pages of a work which was celebrated some half-century agoâRudolphiâs Grundriss der PhysiologieâI was interested to find a clear recognition of this biological principle: âAlle Theile aller Organismen,â he says, I. 233, âsie mögen noch so verschieden in ihrem Bau, in ihrer Mischung, und in ihrer ThĂ€tigkeit seyn, sind ohne Ausnahme als organisch und mithin als lebend zu betrachten.â In a note he adds that physiologists have considered certain solid partsâepidermis, nail, hair, and bonesâto be dead; âbut all these are organically developed, and are in direct connection with the other parts.â
25 Virchow, Die Cellular Pathologie, 1860, Lect. I.
26 Beale, Bioplasm, 104.
27 Kölliker, Gewebelehre, 5th ed., 1867, p. 12.
28 Nevertheless there are some facts directly contradicting his conclusions. For example, he considers the axis cylinder of the nerve to be formed material, and agrees with Max Schultze and others as to its fibrillated structure; yet according to Lister and Turner, Gerlach and Frey, the axis cylinder is deeply stained by carmine, and in this respect resembles the nucleus of protoplasm.
29 From the quite recent experiments M. Baillon has submitted to the Académie des Sciences (15th February, 1875), it appears that although cut flowers absorb colored fluids, the roots when intact only absorb the fluid, and reject the coloring matters, by a veritable dialysis.
30 Gerlach cited by Ranke, op. cit., p. 76.
31 Stein, Der Organismus der Infusionsthierchen, 1859, p. 76.
32 Stahl had a profound conviction of the radical difference, though he was not able to point out the conditions involved. See his Disquisitio de mechanismi et organismi vera diversitate.
33 M. Fernand Papillon has shown that animals may be fed with food deprived of phosphates of lime if its place is supplied with magnesia, strontia, or alumina; they make their bones out of these as out of lime. But no such substitution is possible in muscle, nerve, or gland; we cannot replace the phosphate of magnesia in muscles by the phosphate of iron, lime, or potash, as we can replace the iron of a wheel by steel, copper, or brass.
34 Anatomy resolves the Tissues into Organites (cells, fibres, tubes); here its province ends, and that of Chemistry begins by pointing out the molecular composition of the Organites.
35 This luminous conception, though vaguely seized by Pinel, was first definitely wrought out by Bichat. See his Recherches sur la Vie et la Mortâand especially his Anatomie GĂ©nĂ©rale, 1812, I. p. lxx. It was one of the most germinal conceptions of modern times.
36 Just as there go other materials besides canvas to make a sail, and others besides iron to make a windlass, so there go other tissues besides the muscular to form a muscleâthere is the membranous envelope, the nerve, the blood-vessels, the lymphatics, the tendon, and the fat. Even in Contraction there is another property involved besides the Contractility of the muscular element, namely, the Elasticity of the fibrous wall of the muscular tube; but Contractility is the dominant property, and determines the speciality of the function.
37 âLâĂ©lĂ©ment musculaire peut ĂȘtre annexĂ© Ă une foule de mĂ©canismes divers; tantĂŽt Ă un os, tantĂŽt Ă un intestin, tantĂŽt Ă une vessie, tantĂŽt Ă un vaisseau, tantĂŽt Ă un conduit excrĂ©teur, tantĂŽt enfin Ă des appareils tout Ă fait spĂ©ciaux Ă certaines espĂšces dâanimaux.ââClaude Bernard, Rapport sur les ProgrĂšs de la Physiologie gĂ©nĂ©rale, 1867, p. 38.
38 Vulpian, Leçons sur la Physiologie du SystĂšme Nerveux, 1866, p. 581. In a work just published I find M. Luys hesitating at the consistent application of this law. After pointing out the identity of the tissue in cerebrum and spinal cord, he is only prepared to say that we cannot deny that there is no impossibility in admitting physiological equivalence where there is morphological equivalence.âLuys, Actions Reflexes du Cerveau, 1874, p. 14.
39 It is because men converted the result into a principle, and supposed that Life preceded the Organism, that they were led to puzzle themselves over such facts as the continuance of vitality in divided organisms. Aristotle felt the force of the objection: âPlants when divided are seen to live, and so are certain insects, as if still possessing the same Vital Principle (ÏÏ Ï᜔) considered specifically (Ïáż· ΔጎΎΔÎč) though not the same numerically (Όᜎ áŒÏÎčÎžÎŒáż·). Each of these parts has sensation and locomotion for a time; and there is no room for surprise at their not continuing to manifest these properties, seeing that the organs necessary for their preservation are absent.ââDe Anima, Lib. I. Ch. IV. Compare Basso, Philos. Naturalis adversus Aristotelem, Amsterdam, 1649, p. 260; and Taurellus, Contra CĂŠsalpinum, 1650, p. 850; neither of them grappling with the difficulty so firmly as Aristotle.
40 Spencer, Principles of Biology, 1864, I. 153.
41 Comp. Lamarck, Philos. Zool., II. 114.
42 Comp. Spencer, op. cit., II. 362, 363, for good illustrations of this.
43 Agassiz, Essay on Classification, p. 91.
44 âNulla in corpore animali para ante aliam facta est, et omnes simul creatĂŠ exiatunt.ââHaller, Elementa PhysiologiĂŠ, VIII. 148.
45 Quatrefages, Metamorphoses de lâHomme et des Animaux, 1862, p. 42.
46 Von Baer, Ueber Entwickelungageschichte, 1828, I. 221.
47 Curiously enough, while the Nudibranch, which is without a shell, possesses one during its embryonic life, there is another mollusc, Neritina fluviatilis, which possessing a shell in its subsequent life is without one during the early periods, and according to ClaparĂšde begins an independent existence, capable of feeding itself before it acquires one. See his admirable memoir on the Neritina, in MĂŒllerâs Archiv, 1857.
48 Has any advocate of the hypothesis that animals were created as we see them now, fully formed and wondrously adapted in all their parts to the conditions in which they live, ever considered the hind legs of the seal, which he may have watched in the Zoölogial Gardens? Here is an animal which habitually swims like a fish, and cannot use his hind limbs except as a rudder to propel him through the water; but instead of having a fish-like tail he has two legs flattened together, and nails on the toesâtoes and nails being obvious superfluities. Now which is the more rational interpretation, that these limbs, in spite of their non-adaptation, were retained in rigid adherence to a Plan, or that the limbs were inherited from an ancestor who used them as legs, and that these legs have gradually become modified by the fish-like habits of the seal?
49 Milne Edwards, Intro. à la Zoologie Générale, 1851, p. 9.
50 Von Baer, op. cit., I. 203.
51 Wolff, Theorie der Generation, 1764, § 67. The reader will find abundant and valuable corroboration of this biological principle in Sir James Pagetâs Lectures on Surgical Pathology.
52 Von Baer, Selbstbiographie, 1866, p. 319.
53 Milne Edwards, Intro. à la Zoologie Générale, 176.
54 Von Baer, Ueber Entwickelungsgeschichte, I. 147.
55 Lotze, art. Lebenskraft, in Wagnerâs Handwörterbuch der Physiologie, p. XXVI.
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