Chapter V: Part 5

_Bacteria._—Another and even more important chapter in the history of air-wafted organisms was opened by the indefatigable Leeuwenhoek. In 1683 he wrote a letter to the Royal Society which makes mention for the first time of bacteria, which he found upon his own teeth, and described as minute rods; some of them moved with surprising agility. For nearly two hundred years little more was done. A few bacteria were named and classified, and there the matter rested until Schwann proved experimentally that putrefaction is just as much the work of living microscopic organisms as alcoholic fermentation. In 1857 and the following years Pasteur not only confirmed the work of Schwann, which had been received by the majority of chemists with distrust, but went on to show that the lactic, butyric, and ammoniacal fermentations also depend upon the activity of bacteria. The happy thought struck him that they might be studied alive—a possibility which he soon realised in practice, and upon which the new science of bacteriology largely rests. From about the year 1873 he began to occupy himself seriously with contagion, which he suspected to be connected with specific aerial germs. Davaine and others had years before observed in the blood of sheep and cattle which had died of "charbon" (anthrax) minute "bâtonnets" (bacilli). Pasteur's published results induced Davaine to ask whether his "bâtonnets" might not be the cause of "charbon." Again, it was Pasteur's results which induced Lister to make experiments in the field of antiseptic surgery. Pasteur wasted no time upon the curiosities of bacterial life. His first studies on fermentation suggested that specific diseases may be propagated by microscopic germs, and that such cases of spontaneous generation as had hitherto escaped refutation might be explained by the access of live dust. The identification and biological history of the organisms interested him only as a step towards sure methods of controlling, and, if necessary, destroying, them; of mitigating their virulence by inoculation; of rendering animals immune against them; or of stamping out the disease by isolation. All this is happily too well known for repetition here. The story, with its many dramatic incidents, can be read in the pages of Vallery-Radot.

Hardly less important than the bacteria which destroy life or endanger the products of human industry are the beneficent forms, some of which have in all ages co-operated with man, while others can only be employed by those who possess knowledge and skill. None are so important to our welfare as the bacteria which renew the fertility of the soil. But for the soil-bacteria farm-yard manure would be useless to the crop, for it is they which render it fit for assimilation. Now the bacteria of the soil have their natural enemies, the most mischievous being certain Protozoa, such as Amœba and its kindred. As soon as this fact was grasped, likely remedies were thought of; indeed, one remedy was suggested without any guidance from theory by a vine-grower of Alsace, who treated his soil with carbon disulphide to destroy phylloxera, and found that in so doing he had notably enhanced its fertility. Heating to the temperature of boiling water destroys the soil-protozoa and at the same time the bulk of the soil-bacteria. The bacteria, however, soon multiply more than ever by reason of the absence of their enemies, and a soil cleared of protozoa yields for a few years appreciably richer crops. Of other useful bacteria the briefest notice must suffice. Wine, beer, cheese, and tobacco owe to certain of them distinct flavours, for which the customer is willing to pay high. Leather in certain stages of manufacture, indigo, and woad require the access of other forms. If we also bear in mind the part which yeast plays in the every-day manufacture of bread, wine, and beer, and the part which the vinegar-mould plays in the manufacture of acetic acid, we shall get some notion of the industrial importance of the various micro-organisms. Not a little of the control which we exercise over them we owe directly or indirectly to Pasteur.

The career of Pasteur exhibits a striking unity. His first research, which dealt with a subject so remote from the ordinary studies of the biologist as the crystalline forms of tartrates, made him acquainted with activities, hitherto unsuspected, of minute forms of life. The hope of aiding the industries of Lille, Orleans, and France kept him long engaged upon ferments. If he turned aside to examine the superstition of spontaneous generation, it was to protect his methods from misconstruction. An apparent break in his programme of work was forced upon him by the silkworm pestilence. It proved to be no real break, for pébrine and flacherie were both bacterial diseases. At a comparatively early date (1863) he wrote that his chief ambition was to throw light on the spread of contagious diseases; he could not then foresee that he was destined, not only to elucidate, but in a measure to control them. Around his tomb are inscribed words, each of which commemorates a signal service to his fellow-men: "1848, Molecular dissymetry. 1857, Fermentations. 1862, Spontaneous generation. 1863, Studies of wine. 1865, Silkworm diseases. 1871, Studies on beer. 1877, Contagious diseases of animals. 1880, Vaccination against contagious diseases. 1885, Prevention of hydrophobia." These manifold researches form a continuous chain, each being linked to what precedes and follows. The devotion by which all were inspired, beginning with devotion to science and the fatherland, ended by embracing all mankind.

* * * * *

Biology, which in the sixteenth century sent out only a few feeble shoots, has now become a mighty tree with innumerable fruit-laden branches. The vigour of its latest outgrowths encourages confident hopes of future expansion.

[44] Titius of Wittenberg, who published in 1766 what is commonly called Bode's law of planetary distances, objected to the Linnean system on the ground that it multiplied the principle of division. (_De divisione animalium generali_, 1760.)

[45] _Origin of Species_, chap. xiii.

[46] _Geol. Survey Memoirs_, 1846.

[47] By a curious and no doubt accidental coincidence, Darwin employs the same remarkable metaphor which had occurred to Iordanes in the sixth century A.D. Iordanes calls the north the _officina gentium_.

[48] Introduction to _Entomology_, Introductory Letter.

[49] _Life and Letters_, Vol. I., chap. ii.

[50] Darwin, _Variation of Plants and Animals under Domestication_, Concluding Remarks.

CHRONOLOGICAL TABLE

1200-1850

(The date of a discovery is the date of first publication, where this is known.)

1202. Arabic numeration introduced into Europe by Leonardo of Pisa
(Liber Abaci); it spread slowly, and did not become universal till the
middle of the seventeenth century.

1214-1294. Roger Bacon.

1265-1321. Dante.

1271-1295. Travels of Marco Polo.

1304~1374. Petrarch.

1324?-1384. Wycliffe.

1340?-1400. Chaucer.

1410. Wood-engraving introduced about this time.

1423. Earliest known block-book.

1450? Mazarin Bible, printed by moveable types.

1453. Taking of Constantinople by the Turks.

1466?-1536. Erasmus.

1471-1528. Albert Durer.

1472-1543. Copernicus.

1475-1564. Michael Angelo.

1477-1576. Titian.

1483-1520. Raphael.

1483-1546. Martin Luther.

1492. First voyage of Columbus.

1497-1498. Voyage of Vasco da Gama to India by the Cape.

1516. More's _Utopia_.

1517. Luther's theses.

1519-1521. Mexico conquered by Cortez.

1519-1522. Circumnavigation of the globe by a ship of Magellan's
squadron.

1530-1536. Brunfels' _Herbarum vivæ eicones_. Confession of
Augsburg.

1532. Peru conquered by Pizarro.

1534. Society of Jesus founded by Loyola.

1539. Bock's _New Kreutterbuch_ (without figures); 2nd ed. (with
figures) 1546.

1542. Fuchs' _Historia Stirpium_.

1543. Copernicus' _De Revolutionibus Orbium Celestium_. Vesalius'
_Fabrica Humani Corporis_.

1545. Botanic garden at Padua founded.

1545-1564. Council of Trent.

1547. Botanic garden at Pisa founded.

1551. Belon's _Histoire Naturelle des estranges poissons marins_.

1551-1587. Gesner's _Historia Animalium_.

1553. Belon's _De aquatilibus_, etc., and his _Observations de
plusieurs singularitez_, etc. (Travels in the Levant.)

1554. Rondelet's _De piscibus marinis_.

1555. Belon's _Histoire de la nature des Oyseaux_. Rondelet's
_Universæ aquatilium Historiæ pars altera_.

1564-1616. Shakespeare.

1564-1642. Galileo.

1566. Revolt of the Netherlands.

1571. Battle of Lepanto (advance of the Turks checked).

1571-1630. Kepler.

1572. Massacre of St. Bartholomew.

1576. L'Obel's _Plantarum seu Stirpium Historia and Adversaria_.

1577-1580. Drake's circumnavigation.

1583. Cesalpini's _De Plantis_.

1588. The Invincible Armada.

1596-1650. Descartes.

1600. Olivier de Serres' _Théâtre d'Agriculture_.

1601. Clusius' _Rariorum plantarum Historia_.

1605. Clusius' _Exoticorum libri decem_.

1610. Galileo'smicroscope invented about this time.

1614. Napier's Logarithms.

1618-1648. Thirty Years' War.

1620. Voyage of _Mayflower_. Bacon's _Novum Organum_.

1621. Aselli re-discovers the lacteals.

1623. C. Bauhin's _Pinax Theatri Botanici_.

1626. Jardin des Plantes founded.

1628. Harvey's _De motu cordis et sanguinis_ published, the lectures
had been delivered in 1614.

1635. French Academy founded.

1638. First authenticated cure of fever by chincona bark (in Peru).

1642. New Zealand and Van Dieman's Land discovered by Tasman.

1642-1727. Newton.

1643. Barometer invented by Torricelli.

1650? Air-pump invented by Otto von Guericke. Thoracic duct discovered
by Pecquet.

1653. Lymphatic vessels discovered by Rudbeck.

1660. Royal Society founded; incorporated 1662. Boyle's _Spring of
Air and its Effects_. Ray's _Catalogus Plantarum circa Cantabrigiam
nascentium_.

1661. Boyle's _Sceptical Chemist_. Passage of blood through
capillaries observed by Malpighi.

1665. Hooke's _Micrographia_.

1666. Académie des Sciences founded. Composition of white light
discovered by Newton.

1668. Redi on the Generation of Insects.

1669. Swammerdam's _Historia Insectorum Generalis_. Malpighi's _De
Bombyce_.

1671-1677. Grew's _Anatomy of Plants_; collected in one volume, 1682.

1672-1679. Malpighi's _Anatome Plantarum_; collected in his Opera
Omnia, 1686.

1673. Malpighi's _De formatione pulli in ovo_. Leeuwenhoek's first
paper published by the Royal Society.

1675. Greenwich Observatory founded. Velocity of light determined by
Roemer.

1676. Willughby's _Ornithologia_.

1677. Spermatozoa discovered by Hamm.

1680. Yeast-cells discovered by Leeuwenhoek.

1682. Ray's _Methodus Plantarum_.

1683. Bacteria discovered by Leeuwenhoek.

1687. Newton's _Principia_.

1691-1694. Camerarius on the sexes of flowering plants.

1702. Hydra discovered by Leeuwenhoek.

1711-1776. Hume.

1723-1790. Adam Smith.

1725. Vico's _Scienza Nuova_.

1734-1742. Réaumur's _Histoire des Insectes_.

1736-1810. Watt.

1737. Linnæus's _Systema Naturæ_; last edition by Linnæus, 1766.
Linnæus's _Genera Plantarum_.

1737-1738. Swammerdam's _Biblia Naturæ_ published; written long
before.

1738. Linnæus's _Classes Plantarum_.

1740-1761. Roesel von Rosenhof's _Insecten-Belustigungen_ begun.

1744. Trembley's _Polype d'eau douce_ (Hydra).

1745. Bonnet's _Traité d'Insectologie_ (aphids, Nais).

1748. Montesquieu's _Esprit des Lois_.

1749-1804. Buffon's _Histoire Naturelle_, the last volumes posthumous.

1752. Identity of lightning and electricity demonstrated by Franklin.

1753. British Museum founded.

1755. Black's experiments on carbonic acid and alkalis.

1759. C. F. Wolff's _Theoria Generationis_.

1760. Lyonet's _Traité Anatomique_, etc. (larva of goat-moth).

1770. New South Wales discovered by Captain Cook.

1775. Priestley's experiments on the restoration by green leaves
of air vitiated by combustion or respiration, and on
"dephlogisticated air" (oxygen). Adam Smith's _Wealth of Nations_.

1777. Spallanzani's experiments on the spontaneous generation of
minute organisms.

1781. Uranus discovered by Herschel. Leroy's _Lettres sur les Animaux_
(first collected edition).

1784. Cavendish's _Experiments on Air_ (composition of water).

1785. Hutton's _Theory of the Earth_.

1787-1789. Lavoisier's _Méthode de nomenclature chimique_ (1787) and
_Traité élémentaire de chimie_ (1789).

1789. First French Revolution. A. L. de Jussieu's _Genera Plantarum_.
White's _Natural History of Selborne_.

1790. Goethe's _Metamorphosen der Pflanzen_.

1791. Galvani's experiments on animal electricity.

1792. Sprengel's _Entdeckte Geheimniss der Natur_. F. Huber's
_Nouvelles Observations sur les Abeilles_.

1796. Cuvier on recent and fossil elephants.

1798. Jenner's _Inquiry_ (vaccination against small-pox). Lithography
invented by Senefelder.

1799. William Smith's _Order of the Strata and their Embedded Organic
Remains_.

1799-1825. Laplace's _Mécanique Celeste_.

1800. Volta's electric pile.

1807. Dalton's Atomic theory. Davy's decomposition of potash and soda.

1811. Motor and sensory roots of spinal nerves discovered by Bell.

1812. Cuvier's _Ossemens Fossiles_.

1816. Cuvier's _Règne Animal_.

1819. Electro-magnetism discovered by Œrsted. Chamisso's _De Salpa_.

1823-1831. Pollen-tubes traced to the ovule (Amici, Brongniart, Robert
Brown).

1827. Discovery of mammalian ovum by Baer.

1828-1837. Baer's _Entwickelungs-geschichte_.

1830-1832. Lyell's _Principles of Geology_.

1835. Cell-division in plants observed by Mohl.

1837. Caignard-Latour's demonstration that alcoholic fermentation is
due to living organisms.

1839. Schwann and Schleiden's cell-theory.

1840-1849. Joule's determination of the mechanical equivalent of heat.

1841. Faraday's discovery of electric induction.

1846. Discovery of Neptune by Leverrier and Adams. Agassiz and
Buckland's announcement of extensive glaciation in Scotland.

1848. Discovery of the antheridia of ferns by Suminsky.

1849-151. Hofmeister's comparative studies of the higher cryptogams
and the flowering plants.

1809-1851. Charles Darwin.

1822-1895. Louis Pasteur.

THE SUB-DIVISIONS OF BIOLOGY

Morphology:
Anatomy.
Minute Anatomy.
Comparative Anatomy.

Embryology.

Physiology (including adaptations to the conditions of life).

Psychology of Animals.

Classification.

Geographical Distribution.

Palæontology.

All these divisions, except Psychology, apply both to plants and animals. Many other modes of division have been proposed.

BIBLIOGRAPHY

[It will be readily understood that the literature of Biology is enormous, as a single fact will show. Half a century ago Dr. Hagen compiled a list of books and papers relating to Entomology alone. Though far from complete, it filled a thousand pages, and if brought down to the present date would probably fill a thousand more. The student who tries to follow in some detail the history of any branch of Biology must read books in half-a-dozen languages, and work continually in large public libraries. We shall attempt no more in this place than to mention a few books which can be procured and read by those whose leisure and knowledge of the subject are limited.]

History of Biology or its Sub-Divisions.

Carus, V. _Geschichte der Zoologie_. 1864 foll.

The French translation by Hagenmuller and Schneider (1880) will be
preferred by some.

Cuvier, G. _Histoire des Sciences Naturelles_. Publiée par M. de Saint-Agy. Two vols., 1841. Taken down from Cuvier's lectures, but not revised by him.

Though far from trustworthy (the first volume especially), this
history mentions many interesting facts, and suggests inquiries which
may be pursued with advantage.

Foster, Sir M. _Lectures on the History of Physiology_. Cambridge Natural Science Manuals, 1901.

Green, J. R. _History of Botany_, 1860-1900. A continuation of Sachs's History. Clarendon Press, 1909.

Sachs, J. _History of Botany_, 1530-60. English translation. Clarendon Press, 1889.

An outline of the History of Palæontology is prefixed to Zittel's _Handbuch der Palæontologie_, Bd. 1. (1876-80). English translation, 1900-2.

The ninth edition of the _Encyclopædia Britannica_ often contains useful references. See for example the articles Biology, Embryology, Medicine, Parasitism, and Zoology.

Biographical dictionaries are of course indispensable. _The Dictionary of National Biography_, the _Biographie_ _Universelle_, the _Nouvelle Biographie Universelle_, the _Allgemeine Deutsche Biographie_, and the _Biographie Nationale de Belgique_ will be frequently consulted.

* * * * *

Among the old authors who can be read for pleasure as well as for profit the present writer would include:—

Baker, H. _The Microscope Made Easy._ Second ed., 1743.—_Employment for the Microscope._ 1753.

Belon, P. _Observations de plusieurs singularitez et choses mémorables trouvées en Grece, Asie, Judée, Egypte, Arabie, et autres pays estranges._ 1553.

—— _Histoire de la nature des Oyseaux._ 1555.

Buffon, Comte de. _Histoire Naturelle._ Forty-four vols., of which thirty-six appeared during Buffon's lifetime. 1749-1804. Selected passages only.

Cuvier, G. _Ossemens Fossiles._ 1812. Fourth ed. in ten vols., besides two of plates, 1834-36. Selected passages only.

Hooke, R. _Micrographia._ 1665.

Huber, F. _Nouvelles observations sur les Abeilles._ 1792. Second ed., two vols., 1814.

—— J. P. _Recherches sur les mœurs des Fourmis indigènes._ 1810.

Le Roy, G. _Lettres sur les Animaux._ 1781. Reprinted, 1862.

Linnæus, C., and his Pupils. _Amœnitates Academicæ._ Seven vols., 1749-69.

Contain interesting discussions here and there among much that is now
valueless.

—— _Lachesis Lapponica; or, A Tour in Lapland._ Translated by Sir J. E. Smith from the original diary. Two vols., 1811.

Ray, J. _Catalogus Plantarum circa Cantabrigiam nascentium._ 1660.

Réaumur, R. A. F. de. _Histoire des Insectes._ Six vols. 1734-42.

Redi, F. _Experiments on the Generation of Insects._ Translated from the Italian edition of 1688 by Mab Bigelow. Chicago, 1909.

Roesel von Rosenhof, A. J. _Insecten-belustigungen._ 1746-61.

Turner, W. _On Birds._ 1544. Translated by A. H. Evans, 1903.

INDEX

AFFINITY, 17, 51

Agassiz, 122

Albrecht, 61

Aldrovandi, 13

America, discovery of, 24, 112

Aristotle, 2, 16, 17 _n._, 30, 39, 45, 47, 63, 73, 102 _n._

Aselli, 21

BACON, FRANCIS, 39

—— Roger, 28

Bacteria, 137

Baer, Von, 66, 102, 104, 121, 127

Bagehot, 135

Baker, 67, 69

Barry, 106

Belon, 13

Bernard of Breydenbach, 23

Bestiaries, 6, 23

Bichât, 105

Bock, 9, 12, 37, 124

Bonnet, 45, 60

Bonpland, 118

Bossuet, 66

Brown, 105 _n._

Brunfels, 9, 12

Buffon, 40, 45, 63, 68, 71, 94 _n._, 95, 120, 130

Busbecq, 113

Butler, 67

CAIGNARD-LATOUR, 137

Caius, 19, 67

Camerarius, 48

Cesalpini, 12, 17 _n._, 34, 37, 80, 85

Chamisso, 100

Charlemagne, 25

Clodd, 65 _n._

Clusius, 111, 113

Cole, 86

Compton, 116

Copernicus, 20

DARWIN, C., 46, 66, 75, 91, 92, 120, 121, 124

—— E., 120

Davaine, 138

Descartes, 69

Dioscorides, 4

Dumas, 106

Duverney, 36

ENCYCLOPÆDIC Naturalists, 12

Erasistratus, 4

Evelyn, 111, 115, 116

Experiments of ancient Greeks, 3

FABRICIUS, 21

Fagon, 115

Flemings, 26

Fontana, 105 _n._

Forbes, 131

Fries, 17

Frisch, 37, 67

Fuchs, 9, 12

GAERTNER, 86

Galen, 4, 21

Galileo, 28

Galton, 63 _n._, 135

Geer, De, 37, 68

Gerarde, 20

Gesner, 11, 13, 17 _n._, 18, 19, 20, 113

Goethe, 80, 81, 84, 85

Greenhouses, 114

Grew, 32, 47, 86

HALES, 68, 77

Hamm, 34

Harvey, 21, 102

Hedwig, 87

Heide, 37

Helmont, Van, 77, 136

Herophilus, 4

Hofmeister, 83, 85, 108, 109, 122

Hooke, 29, 34, 37, 105

Hothouses, 114

Huber, 68, 77

Humboldt, 118

Hume, 72

Hutton, 66

INGENHOUSZ, 79

JUSSIEU, B. de, 51

—— A. L. de, 51

KANT, 120

King, 36

Kirby, 68

—— and Spence, 55, 133

LAMARCK, 46

Laplace, 120

Leeuwenhoek, 32, 40, 58, 60, 68, 86, 106, 137

Leibnitz, 45, 64

Leroy, 68, 73

Lessing, 120

Lindsay, 86

Linnæus, 48, 49, 52, 64, 80, 82, 85, 87, 90, 92, 124, 130

Lister, Lord, 138

—— M., 35, 43, 67

L'Obel, 12, 26, 124, 130

Locke, 70

Lyell, 66, 67, 94, 121

Lyonet, 34, 58, 60, 61, 67

MALPIGHI, 32, 36, 40, 45, 47, 127

Marco Polo, 23

Master, 36

Mattioli, 113

Medicine and botany, 7

Méry, 37, 38, 67

Micheli, 87

Microscope, 28, 48

Middle Ages, 5, 6, 25

Millington, 47

Mohl, 106

Montagu, 68

Montesquieu, 63, 120

Morgan, Lloyd, 74

Morison, 86

Moufet, 20

NEEDHAM, 40

Newton, 63

OLIVER and Scott, 83, 85

_Ortus Sanitatis_, 16

PALEY, 133

Palissy, 34

Pallas, 46

Parkinson, 20

Pasteur, 136

Pecquet, 22

Perrault, 36, 37, 67

Peter Martyr Angierius, 24

Physiologus, 6

Pliny, 5

Plumier, 115 _n._

Pope, 45

Poupart, 37, 38, 67

Prévost, 106

Priestley, 77

QUACKELBEEN, 113

RATHKE, 104, 127

Ray, 17 _n._, 22, 35, 38, 41, 48, 68, 124

Réaumur, 37, 40, 54, 60, 64, 68, 70, 87

Redi, 39

Rhineland, 11

Roesel von Rosenhof, 67, 69, 100

Rondelet, 13

Rudbeck, 22

SARS, 101

Saussure, De, 79

Schleiden, 105

Scott and Oliver, 83, 85

Schwann, 105, 106, 137

Seneca, 28, 113

Serres, Olivier de, 26

Smith, 35

Socrates, 133

Spallanzani, 40

Spence, 68

Spencer, 122

Sprengel, 89

Stenson, 34

Suminski, 108

Swammerdam, 29, 37, 38, 40, 70, 86, 103, 106, 133

THEOPHRASTUS, 2, 47

Titius, 124 n.

Tournefort, 38

Tradescant, 115

Trembley, 57

Turner, 18, 67

Tyson, 36

VALLISNIERI, 40

Vesalius, 20, 21

Vico, 63

Voltaire, 35

WALLACE, 120

Wallis, 22

White, 68

Wolff, 80, 82, 84, 85, 103

Woodward, 34

Wotton, 18

YEAST, 136

PRINTED BY WATTS AND CO., JOHNSON'S COURT, FLEET STREET, LONDON, E.C.

End of Project Gutenberg's History of biology, by Louis Compton Miall