INDEX

Absorption from alimentary canal, [129]
Accelerator nerves of heart, [237]
Accommodation of the eye for distance, [391]
for light, [390]
Acromegaly, [93]
Addison’s disease, [91]
Adrenalin, action on the kidney, [209]
formed in suprarenal capsule, [92]
Air, quantity inspired, [173]
quantity needed by individual, [191]
Air-cells of lungs, [168]
Albumin made by plants, [12]
Alcohol, effect on nerve conduction, [301]
Alimentary canal, morphology of, [98]
nerves of, [104]
Altitude, highest, attained by climbers, [187]
Alveoli of lungs, their number, [169]
Amides produced from proteins, [119]
Amœba, irritability of its protoplasm, [10]
Amyl nitrite, effect on vascular system, [237]
Anæmia, treatment with iron, [67]
Anæsthetics, influence on protoplasm, [11]
Analysis by animals, [12]
Angina pectoris, [237]
Angler fish, its nerve-cells, [31]
Animal machine and its driver, [354], [358]
Animals, hunting versus hunted, [366]
not reflex machines, [358]
relative insensibility to the knife, [361]
Antitoxins, formation by protoplasm, [20]
Aorta, diameter of, [232]
Aphasia, [352]
Apnœa, condition of arrested respiration, [181]
Appendicitis, increased frequency of, [101]
Appetite, a safe guide, [114]
Arteries, blood-pressure in, [234], [239]
structure of wall of, [233]
Artificial respiration, [183]
Asphyxia, [182]
Association-zones in the cortex of the great brain, [348]
Asthma, due to reflex contraction of small bronchi, [167]
Astigmatism, correction by glasses, [393]
due to modern print, [269]
Attention, effect of, in heightening pain, [361]
Bacteria, diminution of number in intestine on milk diet, [138]
of alimentary canal, [135]
of Bulgarian sour milk, [138]
of the River Ganges, [141]
in an infant’s intestine, [136]
their rôle in nature, [20]
Balance-sheet of body, how drawn up, [149]
Balloon, highest altitude attained in, [187]
Basket-cells in nervous system, [324], [340]
Bat’s squeak, number of vibrations, [418]
Bats, flight not dependent on vision, [381]
Beats in music, explanation of, [407]
Beetle, muscle of, [261]
Belladonna, physiological action, [109]
Bile, composition, [117]
function in regard to absorption of fat, [133]
relation to digestion, [117]
Bile-pigment, origin from hæmoglobin, [69], [82], [118]
Bioplasm, the essential substance of a living cell, [148]
Birds, sense of hearing of, [410]
Blind spot, how filled in, [395]
Blisters, [41]
Blood, amount ejected by heart, [219]
circulation-time, [219]
composition of, [59]
gases of, amount, [190]
tension, [61]
lodged in abdominal veins, [234], [236]
Blood-corpuscles, cellular nature, [28]
life-story, [62]
number, [61]
origin, [63], [64]
structure, [60]
Blood-platelets, [74]
Blood-poisoning, [57]
Blushing, [243]
Bowman’s description of kidney, [200]
discs in muscle, [259]
Brain. Cf. Cerebellum, Cortex of cerebrum
blood-supply of, [352]
Bread, digestion of, [120]
Breathing, mechanism of, [171]
Bruises, explanation of play of colours, [69]
Bulgarian milk-germ, [138]
Capillary vessels, circulation of blood in, [232]
migration of leucocytes from, [232]
structure of their walls, [38]
Carbohydrate foods, chemical composition, [147]
Carbonic acid, carried by blood, [60]
liberation in lungs, [61], [189]
Carbonic oxide, compound with hæmoglobin, [187]
Carnivora, absorption of fat from alimentary canal of, [133]
Cartilage, growth, [28]
Catalysis, [17]
Cell theory, [26]
Cells, constituent parts, [26], [28]
size, [30]
specialization of function in, [35]
Cells of Purkinje in the cerebellum, [303], [340]
Cellulose, digestion of, [137]
Cerebellum, cases of deficiency of, [341]
connections with cerebro-spinal axis, [340]
development of granules of, [299], [303]
lobes, [338]
minute anatomy, [339]
phylogeny, [338]
relation to tone of muscles, [342]
Cerebral hemisphere, an outgrowth towards olfactory pit, [334]
in animals with various sensory endowments, [349]
Cerebro-spinal fluid, [50]
Chemical activity of protoplasm, [12]
messengers, [89], [123]
processes in plants, [15]
Chemiotaxis of leucocytes, [56], [364]
Children, brain in, [346]
development of astigmatism in eyes of, [269]
Chill, catching a, [242]
Chloroform. Cf. Anæsthetics
Cholesterin, [118]
Chromatolysis in nerve-cells, [320]
Chrome-silver method of colouring nerve-tissue, [293]
Chyme, food converted into, [126]
Circulation of the blood, [218]
Circulation-time, [219]
Cirrhosis of liver, [42]
Coagulation of blood, [69]
Cochlea, anatomy, [413]
Cockney dialect, the degradation of vowel-sounds, [439]
Coke-fire, poisonous fumes from, [186]
Cold-spots in skin, [429]
Collaterals of nerves, [297]
Colon, length and disposition of, [101]
Colour-blindness, [385]
Colour-vision, [385]
Colours, reason for apparent fading in twilight, [378]
Conductivity of protoplasm, [248]
Consciousness, does not come within physiological investigation, [360]
its part in animal life, [359]
Control experiments, their value, [72]
Convolutions of brain, [345]
Cooking, effect upon digestibility of meat, [120]
Corneal epithelium, sensitiveness of, [424]
Corpus striatum of brain, [344]
Cortex of cerebrum, discovery of excitability of, [344]
fissures and convolutions, [345]
functional areas, [352]
myelination of its fibres, [345]
sensory and association areas, [346]
structure of, [347]
variations in different animals, [349]
Corti, organ of, its structure, [414]
theories of function of, [416]
Coughing, mechanism of, [180]
Crayfish, tone of claw-muscle of, [273]
Cretinism, [85], [90]
Cricket, chirp of, [261]
Crypts of Lieberkühn, [103]
Curdling of milk, [75]
Dancing, association of sound with movement, [422]
Day’s work, food required for, [151]
Deafness due to sore throat, [412]
Degeneration of nerves after section, [326]
Depressor nerve of the heart, [237]
Diabetes, excretion of more carbohydrate than contained in food, [143]
Dialysis, explanation of the process, [40], [128]
Diaphragm, function in respiration, [171]
Diastases, destructive ferments, [18]
Diet, limits of possible variations in, [153]
of labouring classes, [152]
Digestibility of bread, meat, fish, etc., [120], [125]
Digestion, mechanism of, [96]
vascular changes during, [235]
waits on appetite, [114]
Digitalis, action on heart and kidney, [209]
Diphtheria, antitoxin of, [20]
Diuretics, [209]
Dog’s sense of smell, [370]
Dreams, theory of, [362]
Dropsy, [42]
Drowning, resuscitation from, [183]
Drugs, physiology of, [95]
Ductless glands, [94]
Dyspnœa, difficult respiration, [181]
Ear, anatomy, [411]
bones of, [412]
differentiation into separate sense-organs, [410]
in fishes, [410]
phylogeny, [409]
Eel’s blood injected into mammal, [20]
Effector, an organ which exhibits change in response to stimulation, [253]
Egg-albumin destroyed by blood, [19]
Electric organs, [288]
phenomena of muscles, [279]
Emotions, their relation to vaso-motor changes, [242]
Energy, expended by body, [151]
source of the body’s, [152]
of stimulus compared with energy of muscular response, [254]
Engines, body compared with, [152], [256]
Epiglottis during swallowing, [433]
Equilibrium, maintenance of, in walking, [342]
Erepsin, ferment of intestinal juice, [119]
Errors of sensory judgment, [402]
Excretion, [195]
Eye, accommodation for distance, [391]
adaptation for darkness, [390]
blind spot, [394]
optical defects of, [393]
phylogeny, [334]
refractive media, formation of image by, [391]
Eyeball, abnormalities in shape of, [392]
anatomy, [373]
development, [374]
muscles of, indefatigable, [269]
Fat, absorption of, [131], [132]
accumulation of, relation to foods consumed, [144]
chemistry, [132]
digestion, [133]
laid down in connective tissues, [145]
stored in liver, [145]
Fatigue, causes of, [45], [268]
Fermentation, [16]
Ferments, chemical nature, [18]
classification, [16], [18]
physiological importance, [18]
Fibrin of blood, its antecedents, [75]
Fireflies, source of their light, [291]
Fish, sense of smell of, [365]
supposed to be frightened by noise, [410]
Flatulence, cause of, [114], [125], [136]
Foods, classification, [142]
history of, after absorption, [142]
relative value, [147], [151], [153], [157]
residue after digestion and absorption, [194]
Foramen ovale of heart, sometimes perforate, [218]
Frigate-bird, turbinate bones of, [166]
Frog, supposed to be found entombed in rock, [164]
Functional interdependence of organs, [94]
Functions transferred to other organs, [87]
Gall-stones, cause of formation of, [118]
Galvani’s observation of contraction of a frog’s muscles, [277]
Ganges, purifying water of, [138]
Ganglia of sympathetic chain, function, [325]
Ganglion-cells of retina, [376]
spinal, [299], [333]
Gaseous tension, meaning of expression, [188]
Gases of blood, their exchange in the lungs, [184]
Gastric glands, structure, [123]
juice, amount secreted, [114]
composition, [114]
digestive action, [115]
Gelatin as article of diet, [158]
Giant cells, [65]
Glands, vaso-motor nerves of, [109], [241]
Glycogen, formula, [147]
as muscle food, [148]
stored in liver, [147]
Goitre, cause of, [84]
Granules, appearance of, in glands, [110]
of cerebellum, development of, [299], [303]
Grey matter, formation of paths in, [356]
Growth, a function of protoplasm, [24]
a reaction to work, [47]
Hæmatin, [68]
Hæmatoidin, [68]
Hæmochromogen, [68]
Hæmoglobin, crystalline form, [66], [186]
formula, [66]
as oxygen carrier, [66], [186]
spectrum, [68], [185]
Hæmophilia, non-coagulability of blood, [76]
Hallucinations, [362]
Headache, a pain in the scalp, [106], [319]
the brain’s warning of fatigue, [269]
from strain of eye-muscles, [268]
Hearing, analysis of compound vibrations, [405]
capacity dependent upon education, [422]
Hearing, Helmholtz’s theory of analysis of sounds, [419]
range of sensations, [418]
sense of, [404]
upper limit, [418]
Heart, anatomy, [217]
automatism of, [238]
development, [218]
murmurs, [229]
muscular tissue, minute structure, [261]
nerves regulating beat, [237], [239]
sounds of, [228]
valves, their mechanism, [226]
work done by, [219], [223]
Heat, production of, by muscles, [254], [256]
Heat-spots in skin, [429]
Helmholtz’s theory of organ of Corti, [419]
Hering’s theory of colour-vision, [388]
Hormones, meaning of term, [89], [124]
of pancreas and liver, [127]
of stomach, [123]
Humours in ancient medical theory, [79]
Hunter, experiment of grafting cock’s spur in its comb, [47]
Hydrochloric acid, part taken in digestion, [114]
Hydrophobia, protective inoculation, [78]
Hyperpnœa, excessive respiratory efforts, [182]
Hypoblast, a layer of the embryo, [97]
Illusions of movement, [335], [384]
of size and distance, [400]
Immunity, acquisition of, [20]
Impulse of the heart, [225]
rate of passage in muscle, [280]
in nerve, [278], [280]
theory of nerve conduction, [282]
Inhibition, explanation of term, [311]
of reflex actions, [311]
Insects, efficiency of their muscles, [261]
Instinct, due to brain-pattern, [359]
Intelligence of animals, [359]
Internal secretions, [83]
Intestinal juice, digestive action, [119]
Intestine, large, sacculation of its walls, [101]
small, folds and glands of mucous membrane, [102]
Intestines, movements of, [103]
nerves of, [105]
size and situation, [100]
Iodine, importance of, to economy, [89]
Iodothyrin, goitre due to deficiency of, [90]
Iris, its function in regulating admission of light to eye, [394]
Iron in food, [67]
in hæmoglobin, [67]
use of, in treatment of anæmia, [67]
Irritability, a function of protoplasm, [10]
Japanese, cultivation of sense of smell by, [370]
Judgment of angles, [402]
of distance and size, [401]
of meaning of sensations, [396], [399]
Kidney, ancestral history, [195]
elimination of indigo by, [207]
of birds and reptiles, [200], [207]
hydrostatic mechanism, [189]
minute anatomy, [196]
Kinæsthetic sensations, absence from dreams, [363]
part played by, in voluntary actions, [354]
representation in cortex of brain, [350], [352]
Knee-jerk, [274]
Labyrinth of ear, [413]
Lactate of ammonia, relation to urea, [13]
Lacteals, lymphatic vessels of alimentary canal, [43], [131]
Lactic acid produced in muscle, [46], [146]
Larynx, closure during swallowing, [433]
structure of, [430]
Latent period of muscle after nervous impulse reaches it, [278]
Laughter, respiratory mechanism of, [180]
Lecithin produced by metabolism of nerve-tissue, [118]
Leech, ganglion-cells of, [298]
Leucocytes as protective agents, [52]
death of, [54], [57]
migration of, [49]
number in lymph and in blood, [49], [61]
origin of, [33], [51]
source of fibrin-ferment, [74]
Leucocythæmia, excess of leucocytes in the blood, [215]
Levers to which muscles are attached, [286]
Light, emission of, by animals, [291]
Lime, influence upon coagulation of blood, [75]
curdling of milk, [75]
Lithates, or urates, constituents of calculi, [213]
Liver, destruction of red blood-corpuscles in, [83]
form and structure of, [160]
former theories of its functions, [129], [163]
manufactures urea and uric acid, [146], [162]
of well fed sheep, [147]
origin of, in vertebrate phylogeny, [34]
Liver stores food, especially glycogen, [46], [145], [147], [161]
Locomotor ataxy, [341]
Ludwig’s view of mechanism of kidney, [200]
Luminous glands, [291]
Lung, exchange of gases in, [173], [184], [190]
nerve-supply, [178]
structure, [168]
Lymph, amount of, in body, [37]
composition, [49]
relation to blood, [51]
Lymph-spaces, [37], [43], [49]
Lymphatic glands, structure of, [54]
Lymphatic vessels, [43]
Malapterurus, electric organs, [288]
immense neurones of, [295]
Manometer for measuring blood-pressure, description of, [238]
Man’s ancestry, [153]
Massage of abdominal viscera, [101]
of muscles, [48]
Meal, the story of a, [120]
Meat, diet consisting solely of, [157]
digestion of, [121]
extracts of, as articles of diet, [159]
Megacaryocytes, [65]
Memory, physiological explanation, [356]
Metabolism, chemical change in living tissue, [12], [273]
Methæmoglobin, [69]
Microscope, its discovery, [26]
Migration of birds, [359]
Milk, call for secretion of, by a hormone, [94]
chemical and physical constitution, [132]
digestion of, [127]
Milk diet, reduction of bacteria in alimentary canal on, [138]
Mind, physiology of, [354]
Mosquitoes, production of sound by, [261]
Motile cells, [32]
Mountain sickness, [187]
Mountains, highest climbed, [187]
Mucous membrane, use of term, [97]
Murmurs, in chest, in diseases of lungs, [169]
of heart, [229]
Muscle, change in appearance under microscope during contraction, [263]
chemistry of contraction, [266]
contraction a phenomenon of osmosis, [258]
electric phenomena of, [278]
means of promoting growth of, [271]
measurement of its power, [285]
nature of impulse which leads to contraction of, [282]
Muscle of heart, its minute structure, [224]
of insects, its efficiency, [261]
plain, its minute structure, [258]
plasma, its coagulation, [266]
rhythm of voluntary contraction, [279]
theory of its structure as a mechanism liberating energy, [234], [255]
tone of, [272]
tracings taken of contracting, [278]
voluntary, its minute structure, [259]
wastes when its nerve is severed, [274]
work done by, proportional to load, [286]
Muscles, arrangement in regard to the bones which they move, [286]
co-operation in lifting a weight, [287]
Muscular energy, source of, [235]
Muscularis mucosæ of alimentary canal, [103]
Musculi papillares of heart, [227]
Music, chords admissible in, [408]
Indian, division of octave, [408]
primitive, prevalence of minor chords, [408]
Musical tones and overtones, [406]
Myelination of nerves, order of, [345]
Myxœdema, dependent on disease of thyroid gland, [85]
Myxomycetes, fusion of cell-bodies of, [27]
Nasal chambers, air warmed in, [166]
Negroes, their long heels, [285]
Nerve, conduction in, theory of, [282]
degeneration, [326]
electrical phenomena, [279]
indefatigable, [282]
regeneration, [326]
structure, [296]
Nerves, depressor, [237]
experiment of crossing, [327]
fifth, [316]
of heart, [239]
of intestines, [426]
protopathic and critical systems of, [425]
secretory, of the salivary glands, [109]
splanchnic, [236]
superior laryngeal, [178]
vagus, [104]
vaso-motor, [239]
Nerve-cells last throughout life, [148]
limitations of their functions, [321]
store of energy in, [320]
transfer of impulses from cell to cell, [177], [300]
their relation to muscle-fibres, [274]
varying size of, [295], [322]
Nerve-centres, [176]
Nerve-force, improper use of expression, [281]
Nerve-impulses, distribution in grey matter, [305]
reinforcement of, [320]
resistance to, at synapses, [306]
Nerve-nets, pericellular, [301], [319]
Nervous system, neuronic and extra-neuronic conduction, [310]
phylogeny of, [332]
Neuro-fibrillæ, [298]
Neurone, origin of term, [293]
transmission of current by, [328]
various types of, [296], [323]
Night-blindness, [378]
Nissl’s bodies, source of nervous energy, [320]
Nitric oxide, combination with hæmoglobin, [186]
Nitrogenous equilibrium, [150]
food, stimulating effect of, [157]
waste, [210]
Nœud vital of Flourens, [176]
Normal diet, [151]
Normal salt-solution, [82]
Nucleo-proteins, source of uric acid, [215]
Odours, classification of, [366]
Œdema, or dropsy, [42]
Olfactory membrane, structure, [366]
Optic nerve, number of fibres, [378]
Organ of Corti, structure, [415]
theory of function, [417]
Organs that have lost their prime functions, [87]
Orientation, sense of, [335]
Osmosis, [40], [128], [201]
cause of muscular contraction, [235]
Osteoblasts, bone-forming cells, [32]
Osteoclasts, bone-eating cells, [65]
Oxygen, amount required per diem, [166]
carried by red blood-corpuscles, [66]
Pain, influence of, upon action, [359]
referred from viscera to surface of body, [316]
relation to sensation, [313], [425]
theory of, [312], [425]
Pancreas, structure, [116]
Pancreatic juice, constitution, [116]
fat-splitting ferment of, [133]
Papillæ of the tongue, various forms of, [97]
Parathyroids, [86]
Pepsin, digestive action, [115]
Peptone prevents coagulation of blood, [77]
Pericellular nerve-nets, [301]
Perspiration, cools the surface of the body, [236]
repressed during fever, [257]
Peyer’s patches of lymph-follicles in intestine, [53]
Phagocytes, germ-eating leucocytes, [60]
consumption of red blood-corpuscles by, [82]
Phosphenes, developed by pressure on eyeball, [383]
Phosphorescence, cause of, [291]
Phrenology, [343]
Pictures, suggestion of solidity in, [401]
Pineal body, phylogeny, [334]
Pituitary body, [93]
Plants, anæsthetized by ether, [12], [24]
their metabolism, [15]
their respiration, [24]
Pleura, lining membrane of chest, [172]
Pleurisy, pain of, [313]
Pleuritic fluid, absorption of, [223]
Pneumonia, changes in lung during, [169]
Portal system of bloodvessels, [80]
regulator of vascular tone, [236]
Power of muscles, [285]
Precipitins formed in blood, [19]
Proteins, absorption by alimentary canal, [145]
chemical constitution, [6]
dietetic value, [157]
fate after absorption, [212]
Protopathic nerves, [425]
Protoplasm, arrangement in cells, [30]
constitution, [7]
Huxley’s definition, [6]
Pulse, cause of, [244]
records of, [245]
variations, [247]
Purgatives, theory of action, [128]
Purkinje-cells of cerebellum, [303], [340]
shadows of retinal vessels, [375]
Pus, origin of, from leucocytes, [57]
Pyramids of cortex of great brain, [346]
Rabbit’s ear, vaso-motor changes in, [235]
Receptor, an organ specially sensitive to stimulation, [253]
Referred pains from viscera, [316]
Reflex action, inhibition of, [311]
of scratching, [330]
vinegar experiment with frog, [307]
Regeneration of nerves, [326]
Renal-portal circulation, [199]
Renewal of tissues, [148]
Rennin, ferment of milk, [16]
Resistance in nervous system, laws of, [177], [307]
Respiration, artificial, [179]
effect on circulation, [221]
a function of protoplasm, [23], [164]
movements of, [171]
nervous mechanism, [175], [179]
in tissues, [165], [193]
Respiratory centre in medulla oblongata, [176], [178], [182]
Respiratory quotient, [174]
Retina, structure, [374]
Retinal pigment, relation to vision, [381]
Rice ordeal, arrest of secretion of saliva, [112]
Rigor mortis, [266]
Rods and cones, respective functions in vision, [378]
Rowing, value of, as exercise, [287]
Saccharin, taste of, [367]
Saline frog, respiration in, [193]
Saliva, chemical constitution, [107]
function of, [96], [107]
Salivary glands, mechanism of secretion, [108]
nerves of, [109], [236]
Salts, absorption of, in alimentary canal, [128]
Scientific method, definition of, [71]
Scratch reflex, in dog, [330]
Sea-sickness, [106]
Secretin, hormone of pancreas and liver, [127]
Secretion, accumulation of granules in cells, and their discharge, [110]
a response to stimulation, [111]
not a process of filtration, [110]
Semicircular canals, their functions, [410]
their positions in space, [335]
Sensations, their apparent fusion, [356]
many which escape attention, [318], [355]
neutralization of one by another, [356]
Sense-organs, origin in vertebrata, [336]
Sensory areas in cortex of the great brain, [348]
Sensory nerves, their connection with cerebro-spinal axis, [304]
Shell-fish, poisonous extract of, [41]
Shivering due to loss of heat from skin, [257]
Sight. Cf. Vision
Skate, electric organs of, [289]
Skilled movements, dependent upon kinæsthetic sensations, [357]
Skin, experiment of cutting nerve, [424]
variety of sensations from, [423]
Sleep, condition of neurones in, [362]
Sleeping sickness, [33]
Smallpox, protection against, [78]
Smell, disappearance of sense of, in later life, [370]
dog’s dependence upon sense of, [366]
reason for mental associations with sensations of, [371]
sensitiveness to mercaptan, [365]
Smells, nice and nasty, [369]
Smoking, mental effect of, [371]
Sneezing on looking at bright light, [317]
Sore throat, cause of deafness, [412]
Soul, Aristotle’s definition, [32]
Sound, mode of conduction, [404]
rapidity of vibrations of, [406], [418]
Sounds of the heart, [228]
periodic and aperiodic, [409]
Spectacles, defects of eyeball which call for, [392]
Speech, derangements of, due to disease of the brain, [353]
mechanism of, [437]
Sphygmographs for recording pulse, [245]
Spinal dog, reflex action in, [330]
frog, reflex action in, [307]
ganglia, development of cells, [299]
Splanchnic nerves, regulation of blood-pressure by, [236]
Spleen, destruction of blood-corpuscles in, [80]
structure, [79]
Squint, correction of double vision in, [397]
Starch, formula, [15]
Star-shapes due to puckering of crystalline lens, [393]
Starvation, statistics of, [156]
Stiffness of muscles, cause of, [45], [271]
Stimuli to muscles and nerves, [248]
Stokes, discovery of spectrum of blood, [68]
Stomach, digestion in, [120]
glands of, [123]
referred pains from, [316]
shape and size, [99]
Stone in the bladder, its cause, [213]
Subconscious self, [355]
Sugars, digestion of, [120], [136]
formulæ, [15]
Sun, apparent size near horizon, [399]
Suprarenal capsules, their structure and function, [91]
Sweetbread as article of diet, [215]
Sympathetic system of nerves, [243], [325]
diameter of fibres, [325]
Synapses of nerve-cells, resistance interposed at, [306]
Synaptases, constructive ferments, [18]
Synthesis by plants, [15]
Tapeworms, resist digestion in the intestines, [21]
Taste, confusion with sense of smell, [364]
localization on tongue, [367]
sense of, in fishes, [365]
sensitiveness to quinine, [369]
Taste-bulbs, their structure, [368]
Tattooing, removal of pigment by leucocytes, [55]
Tea, its dietetic value, [122]
Teeth, [96]
Tendon, the growth of, from cells, [28]
Tension of gases in the lungs, [190]
Tetanus, the vibratile contraction of muscle, [279]
Thoracic duct, discharges lymph into veins, [43], [131]
Thorax, negative pressure in, [222]
Thorns on dendrites of nerve-cells, [300]
Thyroid body or gland, forms an internal secretion, [86]
relation to goitre, [85]
structure of, [85]
Tight-lacing, deformation of organs which it causes, [220]
Tigroids, in nerve-cells, stores of energy, [320]
Tissues, respiration in, [165], [193]
Tone of muscles, [272]
Tongue, as organ of taste, [367]
Tonsils, function as guardians of the fauces, [53]
structure, [52]
Torpedo, electric organs of, [290]
Touch, sensations of, [426]
Toxins produced by microbes, [20]
Urea, amount relatively to proteins consumed, [155]
antecedents of, [146], [212]
chemical formula, [211]
secreted during period of starvation, [156]
Uric acid, amount secreted daily, [213]
artificial production of, [13]
chemical formula, [13], [214]
diathesis, its relation to diet, [140]
due to metabolism of leucocytes, [53], [216]
form in which excreted, [207]
made in the liver of birds, [13]
Urticaria due to abnormal composition of lymph, [41]
Vaccination, protective value of, [22]
Valves of heart, their mechanism, [226]
Vascular system, tone of, [236], [240]
Vaso-constrictor nerves, [236]
Vaso-dilator nerves, [236]
Vegetables, dietetic value of, [139]
digestion of, [125], [137]
Vermiform appendix, [88]
Villi of intestine, absorption of food by, [130]
fat seen in, during active digestion, [134]
Viscera, their insensitiveness to injury, [316], [426]
Vision, colour contrasts, [382]
duration of images, [382]
judgment of distance and size, [411]
solidity, [401]
stereoscopic, doctrine of corresponding points, [397]
Visual purple, [381]
Vital action, definition of expression, [205]
Vivisection, [4]
Vocal cords, structure, [431]
how modified in singing, [435]
Voice, breaking of, in boys, [434]
falsetto, how produced, [435]
range of human, [435]
registers, [436]
Vomiting, [105]
Vowels, synthesis by tuning-forks, [439]
Wandering cells, [33]
Warmth, appreciation of, by skin, [429]
Waste substances, classification, [194]
how eliminated from body, [59]
Waterfall, negative after-image of, [384]
Water-weed, experiment proving that it respires, [24]
Wear and tear of bioplasm, [145]
Wisdom-tooth, tending to disappear, [96]
Yawning, beneficial effect on circulation, [222]
nervous mechanism of, [180]
Young’s theory of colour-vision, [385]
Zymogen, [110]

THE END

BILLING AND SONS, LTD., PRINTERS, GUILDFORD

FOOTNOTES:

[1] Proteïn, subs., proteïd, adj., general terms for complex nitrogenous substances, such as albumin (white of egg), the less soluble globulins, fibrin of blood, casein of milk, etc.

[2] Notice the distinction between filtration and dialysis. If water containing soluble and insoluble substances is placed in a porous jar, the water and the soluble substances pass through the pores of the jar. The rate of flow varies as the pressure. If water containing soluble substances is placed in a bladder, and the bladder is suspended in a vessel of water, some of the substances which it may contain—white of egg, for example—are non-diffusible; others will pass from the water inside the bladder to the water which surrounds it. But every diffusible substance has its own osmotic value. Some pass through the membrane rapidly, soon establishing a condition of equilibrium in the two fluids; others take a long time. Further, if the water on one side of the membrane contains a certain percentage weight of a salt, the molecules of which are large—say sulphate of magnesia—and the water on the other side the same percentage weight of a salt of smaller molecule—say chloride of sodium—water containing the salt of smaller molecule will pass into the water containing the salt of heavier molecule with a certain force. If, to start with, the two solutions are at the same level, the level of the solution containing the less diffusible salt, sulphate of magnesia, will at the commencement of the experiment rise. It is therefore said to exert a greater osmotic pressure than the more diffusible salt—chloride of sodium. Equilibrium will not be established until the fluid on one side of the membrane contains the same number of molecules per unit volume as the fluid on the other side. If the molecules of magnesic sulphate are pictured as oranges, and the molecules of sodic chloride as nuts, it will be understood that equilibrium is not established until the oranges and nuts to the pint on one side equal in number the oranges and nuts to the pint on the other. When these principles are applied to the passage of water containing products of digestion through the wall of the alimentary canal, it is evident that, if we understand all the conditions, the process cannot be explained as merely an exhibition of osmosis. Take the simplest illustration. When blood-serum is placed in the intestine it is absorbed. If it were in a dialyser, there would be equilibrium between the serum inside the intestine and the lymph on the outside. There would be no osmosis. Or, again, supposing water containing 2% of common salt is placed in the intestine, we find that both salt and water pass through into the lymph. In a dialyser water would pass from the lymph (which contains salts equal to about 0·9% of sodic chloride) through the membrane into the stronger solution. A salt-solution needs to be very concentrated to cause water to take the reverse course through the intestinal wall, and so to act as a purgative. When we study absorption from the alimentary canal, we find that its wall, if it wants a salt or any other substance, sets the laws of osmosis at defiance. If the salt is not wanted, the ordinary phenomena of osmosis are exhibited. Sulphate of magnesia (Epsom salt) would be deleterious if absorbed. The intestinal wall behaves towards it like a dead membrane. The salt retains the water in which it is dissolved: possibly water passes out of the lymph into the solution of the salt. The contents of the intestines are in consequence unduly liquid. The salt acts as a purge.

[3] A bullock’s larynx is an admirable object of study. In almost all points of form and structure it is practically identical with the human larynx, and its large size makes it easy to dissect.

Transcriber’s Notes:

The illustrations have been moved so that they do not break up paragraphs and so that they are next to the text they illustrate.

Old or antiquated spellings have been preserved.

Typographical errors have been silently corrected.