Studies in electro-physiology (animal and vegetable)

Front matter

HX641 02777 QP341 .B161 studies in electro-p m

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Preface

I HAVE been encouraged by several medical friends, and particularly by my fellow students, Drs. White Robertson and E. W. Martin, to make an excursion into the realm of Electro-physiology ; a subject which I had previously been reluctant to take up in the declining years of my life owincy to the controversy which any new view of the operating forces of the body would be sure to provoke. But the matter at issue is too important for personal considerations to outweigh a possible advance in knowledge.

For more than half a century theories which were without any real scientific basis have barred the way to progress, and the rebutting evidence hitherto at command was in itself insufficient to compel adequate attention, although it was, upon careful examination, enough to refute the theories in question.

In a former work* of an unambitious character I considered the nature and distribution of nerve force from a new standpoint, and it followed that if I had discovered a fundamental principle my research work must harmonise with established laws and enable me, in accordance with those laws, to explain not only the nature and source of the force but to show how by its means the various functions of the body were called into operation.

The two theories of the nature of the nerve impulse, the physiological and the physical, are, in the present state of our acquaintance with the subject, equally unsatisfactory, but it has always been clear to my mind that upon investigation the body structure should make it manifest whether it was primarily designed for electrical or chemical functions ; or rather, whether it was evident from its * Electro-Pathology and Therapeutics. vii viii PREFACE

structure that electrical action was precedent to chemical change. If not, if, on the contrars^, the body consisted of a congeries of chemical laboratories, with only an occasional suggestion of an electrical circuit, then I was self -deceived.

To this day we electricians do not know if in a galvanic cell electrical begets chemical action or vice versa. But in the form and appearance of a galvanic cell there is nothing to guide us to definite opinion, much less to afford conclusive proof. What is electricity ? There are the onefluid and two-fluid theories. Dr. Le Bon has found that the particles emitted from an electrified point are identical with those of radimn ; carbon when suitably treated will give off a form of energy resembling electricit}^ but which can be shown to be some other element — if electricity is an element. We talk glibly of ions and electrons — although we know very little about them — and are constantly advancing new theories as if they wereiav>'S, and endeavom'- ing, and failing, to make results agree with them. There is only one law, and upon that law all creation is founded ; one law for the living and a modification of it for the dead. There are, of course, differences of structure and jDcrfection of structure, but the same law, as I hope to show in these pages, governs without exception everything that lives upon this earth, animal and vegetable alike.

A. E. BAINES.

London. 1918.

Table Of Contents

Page

PRF.FAP.E .... - - - VII

ERRATA

Part I Electrical Structure And Function In Plant Life

^ GENERAL - - - - - 3

DO VEGETABLES AND FRUITS POSSESS CAPACITY ? 17

SOME SEEDS IN THEIR ELECTRICAL ASPECT - 22

THE ELECTRODES AND ELECTROLYSIS - - 35

PRIMARY OR SECONDARY CELLS ? - - 36

WATER IN ITS RELATION TO PLANT LIFE - 38

THE EFFECT OF ELECTRICAL STIMULATION

UPON GROWTH - - - - 39

THE EMPLOYMENT OF ELECTRICITY IN AGRI- CULTURE - - - - - 42

NOTE FOR GUIDANCE IN TESTING - - 44

Part II Studies In Electro-physiology: Review Of Electro-physiological Research 49

CAUSES WHICH HAVE CONTRIBUTED TO ERROR 54

THE NATURE OF THE NERVE IMPULSE - - 73

INDUCTIVE CAPACITY - - - - 91

CELL REPRODUCTION - - - - IQS

ix

X TABLE OF CONTENTS

Part II. Continued.

Faob

SEGMENTATION OF THE OVUM - - 110

ANIMAL MAGNETISM - - - - 116

SOME EVIDENCES OF THE LAW - - 118

AMOEBOID MOVEMENT - - - - 138

STRIATED MUSCULAR TISSUE - - - 144 SARCOLEMMA AND NEURILEMMA - ^161

OTHER INSULATING PROCESSES - - 161

TERMINATION OF NERVES IN MUSCLE - - 165

DENDRONS AND SYNAPSES - - - 168

CONNECTION OF MUSCLES AND BONES - 172

RESPONSE OF MUSCLES AND NERVES TO ELEC- TRICAL STIMULATION - - - 178

CARDIAC MUSCLE - - - - 182

PLAIN MUSCLE - - - - 184

NISSL's GRANULES - - - - 189

THE NODES OF RANVIER - - - 192

GANGLION CELLS . - - - 196

UNIPOLAR AND BIPOLAR CELLS - - 203

MULTIPOLAR CELLS - - - - 205 electro-diagnosis - - - - 234 the interpretation of certain electro-physiological phenomena - - 251

ELECTRICAL CONDITIONS OF THE EARTH - 267

ELECTRICITY IN RELATION TO SOME VEGETABLE

LIST OF ILLUSTRATIONS

PART I— /n Colour

ELECTRICAL STRUCTURE AND FUNCTION IN PLANT LIFE

Plate I-II. Apple ..... fa£e p. 10

Plate III-IV. Banana ..... face p. 11

Plate VI. Orange ..... face p. 10

Plate VII-VIII. Lemon ..... face p. 11

Plate IX-XI. Turnip ..... face p. 12

Plate XII. Carrot ..... face p. 13

Plate XIII. Onion ..... face p. IS

Plate XIV-XV. Potato ..... face p. 14

Plate XVI-XVII. Artichoke .... face p. 15

Plate XVIII. Horse-Chestnut Leaf . . . face p. 16

Plate XIX. Ivy Leaf ..... face p. 16

Plate XX. Onion ..... face p. 17

Plate XXI. Onion '..... face p. 17

Fig. 21a. Diagram of Connections {not Coloured) . p. 18

PART I— Black and White

Fig.

22. Section of Horse-Chestnut

23. Section of Horse-Chestnut

24. Showing how Induction takes place

25. Section of Horse-Chestnut Seed

26. Horse-Chestnut Seed

27. Sections of Horee- Chestnut Seed

28. Section of Edible Chestnut

29. Section of Edible Chestnut 80. Acorns

31. Double Acorn in Section

32. Cluster of Cob-Nuts 88. Foliage and Cup of Cob-Nut opened out

xi

Page 23

XII

LIST OF ILLUSTRATIONS

PART^ 11— Black and White

FiGv, 1.

Thumb^pressure upon Electrodes

2. Condenser

3. Conventional Drawings of Condenser

4. Conventional Drawings of Condenser

5. Condenser joined up with Battery

6. Condensers in Parallel

7. Condensers in Series

8. Condensers in Series

9. Condensers in Series

10. Condensers in Series

11. Suggested Connection of Endplates with Muscle

12. Diagram of Connections for Capacity Test 13-20. Illustrating Mitotic Division 21-22. Illustrating Segmentation of the Ovum

23. Illustrating Cell Division

24. Lines of Force of Bar Magnet

25. Lines of Force of Two Bar Magnets 26-33. Illustrating Phases in Cell Reproduction in Animal

34. Fertilisation of the Ovum of a Mammal

35. Oosphere -with Spermatozoids

36. Ganglion Cell (Human)

37. Spore of Vaucheria Sessilis 88. Section of Spinal Cord (Human)

39. Transverse Section through a Root

40. Unipolar Cell of Rabbit

41. Section of a Branch of Usnea Barbata

42. Fibrils in the Sheath of a Nerve-Fibre

43. Cells from a Leaf of Hoya Carnosa

44. Formation of Blastoderm in Rabbit

45. Division of Pollen Mother Cells of Plant

46. Group of Cartilage Cells

47. Division of Pollen Mother Cells of Plant

48. Transverse Section of Sciatic Nerve of Cat

49. Parenchyma Cell from Cotyledon of Plant

50. Fibro-Cartilage Cells

51. Cells from Cortical Tissue of the Stem of a Plant

52. Section of SaUvary Gland (Human)

53. Glandular Colleter of Plant

54. Muscular Fibre-Cell (Human) .

55. A Vegetable Fibre

Page

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104-108

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118-119

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LIST OF ILLUSTRATIONS

Xlll

Part II — -Black and White. Continued.

Fig.

56. Diagram of Pregnant Human Womb

57. Ovule of a Gymnosperm ....

58. Epithelium Cells (Human)

59. Peripheral Protoplasm of the Embryo Sac of Plant

60. Endothelium of a Serous Membrane (Human) .

61. Cells from a Tendril of a Plant .

62. Section across a Nerve Bundle (Dog)

63. Section through a Young Internode of Plant

64. Capillary Vessels of the Air Cells of Lung (Horse)

65. Laticiferous Vessels from Root of a Plant

66. Injected Blood-Vessels of Muscle (Human)

67. United Latex Vessels of Plant

68. Stomata in Different Stages of Opening and Closing

69. Cells from the Leaf of a Plant .

70. Cells from a Staminal Hair of a Plant .

71 . Electrical Diagram of Voluntary Muscular Fibre

72. Physiological Diagram of Voluntary Muscular Fibre

73. Electrical Diagram of Voluntary Muscular Fibre 74-76. Illustrating Expansion and Contraction of Muscle

77. Diagrammatic

78. Connection of Nerve with Muscle

79. Connection of Nerve with Muscle

80. Connection of Nerve with Muscle

81. Sarcomere in Moderate Extension

82. Sarcomere in Contracted Condition

83. Portion of Leg Muscle of Insect

84. Muscle Curve

85. Section of Sciatic Nerve of Cat

86. Section of Screened Cable

87. Termination of Nerve-Fibre in Tendon

88. Plexus of Auerbach

89. Illustrating Molecular Theory of Electricity

90. Synaptic Connections of a Sympathetic Cell 91-91A. A Synapse (Diagrammatic) . 92. A Synapse (Diagrammatic) 93-94. Illustrating the Parallelogram of Forces 95. Muscular Fibre Cell (Small Intestine) - 96-99. Illustrating Contraction of Same (Diagrammatic)

100. Muscle Cells of Intestine

101. Anterior Horn Cell with Processes

XIV

LIST OF ILLUSTRATIONS

Part II — Black and White. Continued.

Fig.

102. Showing a Node of Ranvier .

103. Showing a Node of Bamboo

104. Degeneration of Nerve to Node of Ranvier

105. Diagram of Chain of the Sympathetic

106. Neurons of the Motor Path (Physiological)

107. The same reproduced artificially

108. Forms of Spinal Ganglion-Cells

109. A Unipolar Cell (Rabbit)

110. A Bipolar Cell (Fish)

111. Sketch of Metallic Ball for Electrification

112. A Multipolar Cell (Physiological)

113. A Multipolar Cell (Electrical)

114. A Multipolar Cell (Electrical)

115. A Multipolar Cell (Fish)

116. Reflex Action 117.' Root Fibres of the Cranial Nerves

118. Plan of the Origin of the Fifth Nerve .

119. Pigmented Cells of the Retina

120. Section through the Human Eye

121. Section through the Macula Lutea and Fovea

122. Diagrammatic Section of the Human Retina

123. Scheme of the Organ of Hearing

124. Square Case Kelvin Reflecting Astatic Galvanometer

125. Milled Torsion Head .

126. A d' Arson val Galvanometer .

127. Galvanometer Scale and Lamp

128. Transparent Galvanometer Scale and Stand

129. Paraffin Lamp for use with Galvanometer 130-131. Diaphragms 182-133. Short-Circuit Keys

134. Electrode

135. Thumb-Piece

136. Method of Connecting 137-138. Electrodes

139-140. Diagrams illustrating Ohm's Law 141-142. Diagrams of Fall of Potential 143. Illustrating Deflection in Lobar Pneumonia 143A-143C. Differences of Level and Potential 144-146. Illustrating Earth and Cloud

256-7 . 266-9

SYNOPSIS OF PART I

ELECTRICAL STRUCTURE AND FUNCTION IN PLANT LIFE

Chapter I General

Pagr Application of electricity to the soil — No attempt to ascertain Nature's methods — Experiments not conclusive — The views of Thome and Sachs — Analogies in animal and vegetable physiology — Electricity plays a part in the vegetable as well as in the animal worid — Everj'thing living has a well-defined electrical system — The edible part of a fruit or vegetable is the positive element — ^Dry earth is a non-conductor of electricity — Water required as an electrolj'te — Conservation of energy of vegetable cells — Electromotive force of vegetables, plants and fruits — Plants grown in pots — Electrical stimulation of growth — The recording instrument and electrodes — Sign of the earth and the air — How earth-grown plants, etc., are charged — Method of testing described — Theories examined and disputed — Effect of diffusion or decay — The apple described and illustrated — How a cut apple endeavours to protect itself against decay — The banana illustrated, its -positive and negative systems — ^The tomato illustrated — Difference between one grown in the open and one from the greenhouse — Effect of connecting pot with the earth — The orange and lemon, illustrated and described — Peculiarity of absolute insulation — ^The turnip illustrated — Defective absolute insulation and consequent short life after removal from the soil — No adequate means of protection — Effect of keeping in a moist condition (illustrated) — The carrot, illustrated and described — The onion (illustrated), a compound cell — Difficult to examine galvanometrically — Perfect absolute insulation — Its electromotive force and current — Invaluable as a standard cell ..--..-3 Tubers : The potato, illustrated and described — ^Takes its current from the mother plant — Prolific and unprohfic eyes — How it is enabled to repair injury — How it grows (illustrated) — The Jerusalem artichoke (illustrated) — Takes its electrical supply directly from the earth and differs in other respects from the potato — ^Leaves — Deciduous and evergreen — Differences of insulation and life — The horse-chestnut and ivy (illustrated) - 14

XV xvi SYNOPSIS

Page

Do Vegetables and Fruits possess Capacity ? Answer in the affirmative— ^Experiment with a quince — How the tests were taken — Experiments with onion, rhubarb, apple, banana, turnip and orange described - - - - - - - 17 chapter ii sojme seeds in their electrical aspect

Examination of seeds, in their various stages of development, of great interest — Some analogy between some immature seeds and the human foetus — Some law seems to govern both and also cell-reproduction — The Horse- Chestnut seed illustrated — Method of preparation and testing — Its construction, electrically considered — The insulating membranes and conducting layer — How the seed-pod is charged by the earth and the air — Its influence upon the seed substance — Independent existence of the seed only begun when it falls from the pod — Changes which then take place and how the seed-substance receives charge (illustrated) — The final appearance of the insulating membranes (illustrated) — The secretion of the pod and seed-substance — Chemical composition of the membranes — A contrast — The Edible Chestntjt (illustrated) examined and tested — How different to the horse-chestnut — Weird suggestion of foetus in womb — ^Higher order of growth — Food as well as seed — How it is equipped to serve as both — Its capacity compared with that of the horse-chestnut — Hypothetical explanation of the purpose underlying it — ^The Acokn (illustrated) — How the seeds are joined up electrically — The contacts and insulation — ^Twin seeds and how they are given protection — Cob-nuts (illustrated) — ^How joined up electrically and how insulation is preserved, etc. 22

The Electrodes and Electrolysis : Experiments to determine the

effect of electrolysis upon the deflections observed - - 35

Primary or Secondary Cells ? Probably neither — Cells undergo no disintegration and no change — Cannot be polarised or discharged — ^Length of Ufe in direct ratio to absolute insulation — Effect of short-circuiting — Plants " resting " in late autumn, winter and spring — Constancy of vegetable cells — ^Theoretical explanation of their long-sustained electrical activity - - - 36

Water in its relation to Plant Life : As dry earth is a non-conductor of electricity water is also required as an electrolyte — Experiment with mustard and cress, ferro-sulphate and less water — Some suggestions - ..... 38

SYNOPSIS xvii

Pxas

The Effect of Electrical Stimulation upon Groioth : Currents artificially sent through a root said to retard growth — Statement not warranted by fact — Experiments with potatoes, with plants in greenhouse, and with onions — Question of polarity, not electricity — Variously stimulated onions illustrated - - 39

Chapter III The Employment Of Electricity In Agriculture

Review of the last one hundred and fifty years — Results considered — Chlorosis in plants — Iron and oxygen in plant life — ^Periods of drought — The savoy cabbage - - - - - 42

Note for Guidance in Testing : The electrodes and how to connect

them (illustrated) - - - - - - 44

SYNOPSIS OF PART II

STUDIES IN ELECTRO-PHYSIOLOGY : ANIMAL AND VEGETABLE

Chapter IV Review Of Electro-physiological Research

Present state of knowledge — Galvani, Volta, Humboldt, Aldini, Nobili, Matteucci, Du Bois-Reymond, Radcliffe, Trowbridge — Causes of confusion — Certain factors not discovered - - 49

Causes which have Contributed to Error : Generation and dissipation of nerve force — Insulation of the body — Air and earth — Individuals differ electrically — Conflicting results and the reason therefor — Personal capacity — Capacity of liquids and moist substances — Non-polarisable electrodes — Other electrodes and their reliability — Dr. Longridge's experiments — Dr. Martin's experiments — Other tests of electrodes — Argument — " Suggestion " — The hand-to-hand deflection and thumb-pressure — Structure of the body primarily electrical - - - 54

Chapter V The Nature Of The Nerve Impulse

Rival theories, physiological and physical — Argument that impulse is chemical more in favour of it being electrical — Argument — Professor Rosenthal and peripheric nerves — Inhibition — Velocity

b xviii SYNOPSIS

Page of impulses compared — Retardation — Resistance of copper •wire compared with nerve — Normal E.M.F. and current of man — Effect of capacity — ^Hypothesis of Dr. Martin — Natural dielectrics — Experiments of Dr. Le Bon - - - 73

Chapter VI Inductive Capacity

The effects of capacity — Apparent velocity of current diminished — Condenser described — Connections in parallel and in series — Joint capacity in series — Current and resistance — ^Potential differences — Connection in series-parallel — Condensers of the human body — Reflex action — ^Rates of discharge — Condenser action in cardiac muscle — Influence of capacity upon velocity of the nerve impulse — Specific inductive capacity — ^Dimensions of plain and voluntary muscular fibres — ^To test the human body for capacity, method and diagram - - - - 9i

Chapter VII Cell Reproduction

Mitotic division — The centrosonxe and the attraction sphere — The centriole — ^Division of cell preceded by division of the attraction sphere — Changes in the cell during the process — ^Achromatic fibres and spindle — Chromatin — Chromosomes — Irritability of protoplasm — Cleavage — Repulsion as well as attraction — Nucleus and nucleolus- — Division briefly described - - 103

Segmentation of the Ovum : Hetero and homotypical mitosis — Polar bodies — ^Varying number of chromosomes — Sperm and germ nuclei — Fertilisation — Ascaris megalocephala — Difference from ordinary mitosis — Sexual reproduction in plant life — Mucor and spirogyra — Fucus — Asexual reproduction — Fungi, diatomaceae and protozoa — Importance of nuclei — ^Network in protoplasm — Enzyme action — Vines' description of Karyokinesis - - -- - - - -110

Chapter VIII Animal Magnetism

Alleged magnetic influences in the human body — Not warranted by fact — ^Resemblance of certain phenomena to magnetic control superficial — Geddes and Thomson's diagram of cell-division compared with lines of force of a bar magnet, and with two bar magnets ....... hq

SYNOPSIS xix

Chapter IX Some Evidences Of The Law

Page Phases of cell reproduction, animal and vegetable — Fertilisation of

the ovum and oosphere — Ganglion cell and spore — Spinal cord and root of Phaseolus multiflortis — Unipolar cell and section of branch — Spinal and reticular fibrils (human) and cells from a leaf — Blastoderm of rabbit and pollen mother cells of plants — Cartilage and pollen cells — Section of sciatic nerve and cell of plant — Fibro-cartilage cells and thickened cells from stem of plant — Human and vegetable glands — Cell of plain muscular fibre and a vegetable fibre — Pregnant human womb and ovule of a gymnosperm — Epithelium cells (human) and peripheral protoplasm of embryo-sac of a plant — Endothelium of a serous membrane (human) and cells froni a tendril of a plant — Section across a nerve in the second thoracic anterior root of a dog and section through internode of the short axis of a plant — Capillary vessels of the air-cells of horse's lung and laticiferous vessels of a plant — Sachs and others upon laticiferous vessels in plants — Injected blood-vessels of a human muscle and reticulately united latex vessels of a plant — Irritability of vegetable protoplasm— Similarity of senses — Motor mechanism of plants — Stomata — Stimulation — Sense organs of plants — Specific energies of the sensory nerves — Enzymes — Fats in plants — Wax in plants and fruits — Movement or circulation of protoplasm in plants — Cells from leaf of Elodea and hair of Tradescantia — Rhythnuc movement in plants — Paralysis or destruction of protoplasmic movement — Rate of propagation of stimuli in plants ...... us

Chapter X Amoeboid Movement

Movement apparently spontaneous — Nucleo-protein — All breathing or taking in oxygen — Nature of the movement — Effect of change of temperature, chemical stimuli, electrical stimuli, etc. — Foregoing paraphrased and explained — Live and dead amoeba — The experiment of Ampere — Attraction and repulsion — Experiments of Davy, Le Bon and Arrhenius — Czapec on salt solutions — Inorganic salts in the blood plasma — Rigor or cessation of protoplasmic movement in plants - - - 138

Chapter XI Electro-physiology Of The Motor Apparatus

Huecular tissue — Striated muscular tissue — Anticipation before studj— Sarcolemma and structure of the sarcomeres — Krause's membranes or Dobie's lines — Chemical or electrical action ? —

XX SYNOPSIS

Fasb

Certain electrical laws — ^Physiological aud electrical diagrams — Artificial muscular fibre — ^Discharge or neutralisation of charge — Further diagrams — ^How the nerve-fibres connect Avith groups of sarcomeres — Muscle extended and contracted — The plane of Hensen — Condenser-action — The " Muscle Telegraph " of Du Bois-Reymond — Physiology of muscular fibre considered — Stimuli not various forms of energy — Clear spaces may be " points " — StimuU not discharging forces — Effect of rise or fall of temperature upon muscular fibre — Excised muscle — Difference between the living and the non-living — Comparison with frog, toad and tortoise — Excitability of muscle when nerve dead — Compared with apple — Independent muscular activity reviewed — Wrong to say plants have no nerves — ^Reasons therefor — Effect of poisons upon nerves and plants — Curara and nux vomica — Muscle-curve due to single induction shock examined -------- 144

Sarcolemma and Neurilemma : Both elastic and both dielectric in

character — Argument - - - - -161

Other Insulating Processes : Sciatic nerve of cat — Endoneurium, perineurium and epineurium — The electrical function of lymph — Insulation of submarine and screened land cable — Inductive interference - - - - - - - 161

The Termination of Nerves in Muscle : End -organs — Fibres branch — MeduUated nerve-fibres — Plexuses of involuntary muscle — Each nerve-fibre separately insulated — Plexus of Auerbach - 166

Dendrons and Synapses : Cells of Purkinje — ^Neuroglia and connective tissue — Dendrons, axon and neuron — Cell processes — Synaptic junctions — Contiguous but not continuous structures — Propagation of electric force by molecular action — Sympathetic cell : arborisations — Physiological path of chains of neurons uninterrupted — Synapse compared with condenser — ^Necessity for insulating processes in the body - - - - 168

Connection of Muscles and Bones : Whole action of muscle the sum of the separate actions of all the fibres — Fan-shaped muscles — Semi-pennate muscles — Pennate muscles — Parallelogram of forces — Work performed by muscles conditioned by their attachment to the bones — Sesamoid bones - - - 172

Response of Muscles and Nerves to Electrical Stimulation : Nutrition of the nerves — When impaired — Nerve degeneration and its effect on muscle — Changes in the excitability of muscle — Contractions caused by constant and induced currents — ^Degeneration of motor nerve — Response of muscle to constant current — Afuscular paralysis — Paralysis due to disease - - - 178

SYNOPSIS xxi

Chapter XII Cardiac Muscle

Page Histological diagrams not sufficiently clear — Cardiac muscle intermediate— Each segment considered as a sarcomere — Branch or shunt circuits — Regulation exercised by the cardiac branches of the vagi — Day and night intake of oxygen in relation to the hand-to-hand galvanometric deflection — Inhibition — Effect of an escape of nerve energy, and of certain toxins - - 1 82

Plain Muscle : Very little information — Must be transversely striated — Professor Rosenthal's views — Schafer — The question of a sarcolenuna — Longitudinal striation would only cause flattening — Explanatory diagrams and speculative explanation — How the cells are probably connected up .... i84

Chapter XIII Nissl's Granules

Cells contain organically combined iron, but not in masses as hitherto thought — Mott's researches viith living cells — Nissl's granules the result of coagulation in the dead cell — In the living cell they exist in the form of fine particles - - - - 189

Chapter XIV The Nodes Of Ranvier

Illustration of a typical node — How the nodes occur — Compared with bamboo and canes — Strasburger on the nodes of bamboo — Degeneration of nerve only to node — Uninterrupted continuation of axon questioned — Constriction and increased resistance suggested — Reasons therefor - - - - - 192

Chapter XV Ganglion Cells

Some said to be condensers and some storage cells — Differentiation of the two — Efferent and afferent impulses, and control and regularity of supply — Diagram of motor and sensory paths from spinal cord — The functions of a condenser in telegraphy — Diagram of unipolar and bipolar cells — Maintenance of normal insulation resistance — Physiological and electrical diagrams of motor and sensory paths — Quantity and tension — The views of Dr. Le Bon — Confusion of terms — Electro-cardiograms and ganglia — Thornton's views — Autonomic ganglia — Afferent and efferent fibres - - - - - - - 196 xxii SYNOPSIS

Page Unipolar and Bipolar Cells : The conducting and non-conducting cell-substances — Macallum and Turner — Forms of Leyden jar and condenser — ^Their probable connection — Cells disposed in aggregations of different size — ^The capsule of connective tissue — Continuous with the epineurium and perineurium — Branching of the axis-cylinder process at node of Ranvier — ^Neuro-fibril network within cell body — Every cell not of same structure — Illustrations from Schafer ..... 203

Multipolar Cells : Cells of the cerebral cortex and spinal cord — Construction of an artificial multipolar cell described — Surface area and tension — Physiological and electrical diagrams — Dendrons said to be branch circuits — How to take off efferent and afferent impulses at will — Arrangement of condensers or bipolar cells described and illustrated — Multipolar cell made up of as many Leyden jars or rings as there are dendrons with separate nerve-fibres to each — Illustration from Haeckel — Reflex action illustrated and discussed — Synaptic junctions — Undifferentiated interstitial protoplasm — Storage cells in sensory paths illustrated — ^Not found in motor paths — Connection of voluntary motor fibres with multipolar nerve-cells of the anterior cornu — Direct motor impulses not interrupted in their passage through the brain .... 205

Chapter XVI The Eye And The Ear

The Eye : Strongly suggestive of a compoimd selenium-cell transmitting apparatus — The effect of light upon selenium — Transmitting pictures to a distance — The telectroscope described — Property of selenium — Trans/nission of colour — Colour in relation to white light — The lens of the eye — The iris or diaphragm — Pigment cells illustrated and described — ^The rods and cones — Connections at the fovea and elsewhere — ^The macula lutea — Visual impulses said to begin in the rods and cones on the outer side of the retina — Latter connected functionally, if not structurally, with the nerve filaments that pass to the optic nerve — " Visual purple " — Possible function of the epithelial pigment cells of the retina — Our ignorance of how undulations of light become converted into nervous impulses — Ordinary light and vibrations — The eye illustrated — Vertical section through the macula lutea — Diagrammatic section of the retina — Alleged vibrations of electrons in the retina — Maxwell and the speed of electro-magnetic waves — Duration of the sensation produced by a luminous impression on the retina — Optic nerve said to be a closed circuit — Movement of the pigment cells — Movement of the cones and possibly of the rods - - - - 237

SYNOPSIS xxiii

Page The Ear : Physiological description — Endolymph and perilymph —

Passage of the impulses — The external auditory meatus —

Malleus, incus and stapes illustrated and described — Mechanical

impidse questioned — Mechanism of hearing far from being

satisfactorily settled — Neuro-electrical theory more reasonable

and probable than chemical or mechanical — Proof that it is so —

The fenestra ovalis — Basilar membrane and membrane of

Reissner — Ear, from external auditory meatus to brain , said to

be a telephone system — Auditory nerves closed circuits —

" Faults " and how to test for them .... 228

Chapter XVII Electro-diagnosis^the Galvanometer And Electrodes

Chief requirements in a galvanometer — Its required sensibiHty and period — Illustration of square case Kelvin — Its adjustment — Its advantages and drawbacks — Galvanometers of the d'Arsonval type illustrated — Scales illustrated — The lamp (illustrated) — Types of galvanometer short-circuit keys — Shunts — Connecting wires — Earth connection— The electrodes illustrated and described— Sign of current unimportant — All deflections comparative ---.... 234

Chapter XVIII Ohm's Law

In its application to the human body — Shortly described — In terms of hydrostatics — Further description — Resistance of metallic and liquid conductors — Fluctuation of human E.M.F. — Influence of capacity of condenser-ganglion cells — Variation of potential — Temperature and moisture — Diagrams — Potential differences - 245 The Hmid-to-Hand Deflection : Precautions necessary - - 249

Application of Ohm's Law to Solutions : The researches of Arrhenius - 250

Chapter XIX Interpretation Of Certain Electro-physiological Phenomena

Dielectric substances and structures in the human body — Effect of heat upon all known dielectrics — Formula for calculating the relative resistance of gutta-percha — -Local temperature and local pyrexia and the effect upon local insulation resistance — Maxwell's experiments — Heat and liquid conductors — Effect of heat upon the dielectrics of the body as compared with its effect xxiv SYNOPSIS