!i!*l« 
 
 
 ^B&* 
 
 LIBRARY OF CONGRESS. 
 
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 • Shell ,.W.I>3 
 
 UNITED STATES OF AMERICA. 
 
 
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"HUMAN physiology; 
 
 FIRST EDITION. 
 
 WATKINS. 
 
QJJIZ-COMPEND 
 
 A COMPEND OF 
 
 Human Physiology, 
 
 ARRANGED IN THE FORM OF 
 
 QUESTIONS AND ANSWERS. 
 
 PREPARED AND ESPECIALLY ADAPTED FOR THE 
 USE OF MEDICAL STUDENTS. 
 
 By WM. J. \V ATKINS, M. D., 
 
 GRADUATE OF KENTUCKY MEDICAL COLLEGE, LOUISVILLE, KY. 
 
 First Edition. 
 
 LOUISVILLE, KY.: 
 
 W. J. Watkins, M. D., 508 W. Chestnut St. 
 1 891. 
 

 Entered according to Act of Congress, in the year 1891, by 
 
 W. J. Watkins, M. D., 
 
 In the Office of the Librarian of Congress, at Washington, D. C. 
 
 1891— COPYRIGHT— 1891. 
 
 PRESS OF 
 
 Courier-Journal Job Printing Company 
 louisville, ky. 
 
— TO— 
 
 STUDENTS OF MEDICINE 
 
 THIS LITTLE VOLUME 
 
 IS RESPECTFULLY CONSIGNED 
 
 BY 
 
 THE AUTHOR. 
 
PREFACE TO FIRST EDITION. 
 
 At the present time, when the student is forced by the rapid 
 progress of medical science to imbibe an amount of knowledge 
 which is far too great to permit of an attempt on his part to master 
 it, any volume which contains the "essentials " of a science in a con- 
 cise, yet readable form, must, of necessity, be of considerable value. 
 The trite saying that "there is no short road to knowledge" is, of 
 course, as true as it is old; but as long as the effort is made to 
 " cram " the whole science of medicine into a five months' course it 
 is necessary that the hurried student have condensed books on the 
 most important branches presenting essential facts, so that he need 
 not wade through the more exhaustive and voluminous text-books. 
 
 There is no one desires more than the writer that the depth and 
 scope of medical education be increased ; but, in his belief, the evil 
 at present in existence consists in the fact that medical institutions, 
 by granting a degree " too early," make the short road to knowledge 
 the only one which the student with the average amount of cerebral 
 gray matter can possibly travel. The evil lies with the small 
 amount of time required for the obtaining of the degree. 
 
 The writer of this little book has, at all times, had in view the 
 interests of the medical student, and should it find a place of average 
 appreciation among them, we will consider that our time and 
 trouble have been justly compensated. 
 
Manuals of this kind are in no way intended to supplant any 
 of the text-books {or question pamphlets " without answers " now be- 
 ing used in some schools in this country), but to contain the essence 
 of those facts with which the average student must be familiar, and 
 to arrange the subjects in the form of questions and answers, from 
 the fact that in reading the standard works the student is often at a 
 loss to discover most important points to be remembered, and is 
 equally puzzled when he attempts to formulate ideas as to the man- 
 ner in which the questions will be put in the silent and unavoidable 
 "green room. 1 ' 
 
 In producing this little volume we would acknowledge our in- 
 debtedness to such standard books as Landois, Dalton, Yeo, etc., but 
 for its foundation and basis throughout we are indebted to Mr. 
 Flint's latest revised edition ; but for a great many of our questions 
 we are under many obligations to our old friend and teacher, Dr. 
 Sam. Cochran. W. J. W., 
 
 508 W. Chestnut St. 
 Louisviu,e, Ky., October, 1891. 
 
CONTENTS. 
 
 CHAPTER I. 
 
 Introduction. 
 
 II. 
 
 Chkmical Composition of the Body. 
 
 III. 
 
 Structural Composition of the Body 
 
 IV. 
 
 Blood. 
 
 V. 
 
 Heart. 
 
 VI. 
 
 Fcetal Circulation. 
 
 VII. 
 
 Arteries. 
 
 VIII. 
 
 Capillaries. 
 
 IX. 
 
 Veins. 
 
 X. 
 
 Respiration. 
 
 XI. 
 
 Alimentation. 
 
 XII. 
 
 Mastication. 
 
 XIII. 
 
 Deglutition. 
 
 XIV. 
 
 Digestion. 
 
 XV. 
 
 Small Intestines. 
 
 XVI. 
 
 Pancreas. 
 
 XVII. 
 
 Bile. 
 
 XVIII. 
 
 Large Intestines. 
 
 XIX. 
 
 Defecation. 
 
 XX. 
 
 Absorption. 
 
 XXI. 
 
 Imbibition. 
 
 XXII. 
 
 Lymph and Chyle. 
 
 XXIII. 
 
 Secretion. 
 
 XXIV. 
 
 Mammary Glands. 
 
 XXV. 
 
 Excretion. 
 
 XXVI. 
 
 Skin. 
 
 XXVII. 
 
 Perspiration. 
 
 XXVIII. 
 
 Kidneys. 
 
 XXIX. 
 
 Liyer. 
 
 XXX. 
 
 Spleen. 
 
 XXXI. 
 
 Nutrition. 
 
 XXXII. 
 
 Animal Heat. 
 
 XXXIII. 
 
 Nervous System. 
 
 XXXIV. 
 
 Cranial Nerves. 
 
 XXXV. 
 
 Spinal Accessory. 
 
 XXXVI. 
 
 Hypoglossal. 
 
 XXXVII. 
 
 Tri-Facial. 
 
 XXXVIII. 
 
 Pneumogastric. 
 
 XXXIX. 
 
 Spinal Cord. 
 
 XL. 
 
 Brain. 
 
 XLI. 
 
 Cerebellum. 
 
 XLIL 
 
 Medulla Oblongata. 
 
 XLIH. 
 
 Special Sense. 
 
 XLIV. 
 
 Sympathetic. 
 
 XIvV. 
 
 Reproduction. 
 
 (9) 
 
CHAPTER xi.vi. ewiaw Organs of Generation 
 
 Graafian Follicles, 
 The Parovarium, 
 The Uterus, 
 The Fallopian Tubes, 
 External Organs, 
 The Ovum, 
 VT „ TTr „ Puberty and Menstruation. 
 -\ j a ii. Male Organs of Generation 
 The Testicles, 
 The Vas Deferens, 
 The Vesiculae Seminales, 
 Prostate Glands, 
 Glands of Urethre, 
 VT TrTTT ^ Male Element of Generation. 
 XLVIII. Fecundation and Development of the 
 Ovum, 
 Hereditary Transmission, 
 Changes in Fecundated Ovum 
 Primitive Trace, 
 Blastodermic Layer, 
 Formation of the Membrane, 
 The Amnion, 
 The Allantois, 
 Amniotic Fluid, 
 The Chorion, 
 Umbilical Cord, 
 Membranae Decidua, 
 The Placenta. 
 XLIX. Development of the Embryo 
 The Ovum, 
 Nerveous System, 
 Digestive Apparatus, 
 The Liver of the Embrvo, 
 The Pancreas, 
 The Lungs, 
 The Bladder, 
 The Face, 
 The Eye, 
 The Internal Ear, 
 The Skeleton, 
 
 Development of Genito Urinary Apparatus, 
 External Organs of Generation, 
 The Circulatory Apparatus, 
 Placental Circulation, 
 The Heart, 
 Foetal Circulation. 
 L. Finale. 
 
 (io) 
 
Compend of Human Physiology. 
 
 CHAPTER I. 
 
 HUMAN PHYSIOLOGY. 
 
 What is Physiology? Arts. Physiology is the study of 
 vital phenomena which are always present in all living 
 things, be they animal or vegetable. 
 
 What is Human Physiology ? A study of the functions 
 of the human body as exhibited in the healthy state. 
 
 How is Physiology divided ? Two sub-divisions, known 
 as Animal Physiology and Vegetable Physiology; but it 
 should be remembered that the line of demarkation between 
 Animal and Vegetable Physiology in the lower forms of life 
 is very ill-defined. 
 
 From what is the word Physiology derived ? From a 
 Greek word Qvolc, "Nature," and lo^oc, "a discourse," 
 and in its original meaning was applied to the study of 
 natural history in general, and is really synonymous with 
 the term biology, since it is necessary for the study of either 
 one that vital properties be present in the thing studied. 
 
 Define Vegetable and Animal Physiology? (i) Vegetable 
 Physiology treats of the phenomena manifested by which 
 the several structures of the plant is composed. (2) Ani- 
 mal Physiology treats of the phenomena manifested by the 
 organs and tissues of which the animal body is composed. 
 
 Which is the most important to physicians? Animal 
 Physiology by far most important. 
 
 Describe three most important classes as compared with 
 Human Physiology? (1) " Nutrition," which has for its ob- 
 
 (") 
 
12 COMPEND OF HUMAN PHYSIOLOGY. 
 
 ject the preservation of individual — e. g., digestion, absorp- 
 tion, circulation of the blood, respiration, assimilation, 
 animal heat, secretion and excretion. (2) "Animal" which 
 bring the individual into a physiological relationship with 
 external nature — e. g., sensation, motion, language, mental 
 and moral manifestations. (3) " Reproductive function" 
 which has for its object the multiplication and preservation 
 of the species. 
 
 Is there any means by which Human Physiology can be 
 proven ? Yes. By Anatomy, Chemistry, Pathology, Com- 
 parative Anatomy, Vivisection, the application of Physics, 
 etc., etc. 
 
 What is the chemical basis of the body ? The body may 
 be studied from a chemical or structural point of view. Of 
 the sixty-three elements known to chemists a very small 
 number, comparatively speaking, are found in any quantity 
 in living animal matter; however, traces of them all are 
 frequently present. 
 
 What elements found most in abundance ? Oxygen, car- 
 bon, hydrogen and nitrogen are present in very large pro- 
 portions in all the tissues, and together compose about 
 ninety-seven per cent, of the whole bod3 r , while sulphur, 
 phosphorus, chlorine, fluorine, silicon, chloride-sodium, mag- 
 nesium, calcium and iron are almost indispensable to the 
 economy, but are widely distributed, and appear in much 
 smaller quanties. 
 
 What two great groups of substances make up the body ? 
 Physiological chemistry teaches us that we have in the 
 body two sets, or groups of substances known as nitrog- 
 enous and non-nitrogenous. 
 
 Which is most important ? The nitrogenous perform the 
 most important functions, and, indeed, form all the active 
 portions of the organism ; as the simplest element of these 
 nitrogenous bodies may be mentioned protoplasm. 
 
HUMAN PHYSIOLOGY. 1 3 
 
 What is derived from this ? From this, and entering into 
 the formation of it, are albumins, serum-albumins, and by 
 the outcome of still further differentiation we have albumi- 
 noids, which is chiefly represented by gelatine, last of those 
 products which, though nitrogenous in character, differ 
 from this in that they are intermediate or effete products 
 of tissue manufacture or waste, as, for example, "'urea" 
 uric acid, kreatin and kreatinin. 
 
 What can you say of non-nitrogenous substances ? They 
 consist chiefly of carbohydrates, which contain hydrogen 
 and oxygen in the proportion to form water, as, for exam- 
 ple, starch and sugar. Then we have substances contain- 
 ing oxygen in less proportions than the above, namely, fats. 
 Chloride sodium occurs all through the tissues, as does also 
 water. 
 
14 
 
 COMPEND OK HUMAN PHYSIOLOGY. 
 
 CHAPTER II. 
 
 CHEMICAL COMPOSITION OF THE HUMAN BODY. 
 
 What do you 
 man body ? By 
 the body can be 
 stances, which 
 can be resolved, 
 ical elements, 
 tained, and the 
 in the following 
 
 rtOygen • 
 ^Hydrogen 
 
 rNitrogen 
 ^/Carbon . 
 <?Sulphur . 
 
 /Phosphorus 
 
 ^-Calcium 
 //Sodium 
 
 /Potassium .... L026 
 
 7'Magnesium 
 /-Chlorine . 
 
 /Fluorine 
 ///Iron . . 
 
 //Silicon . . . 
 
 fManganesium 
 
 *Frora Burbaker. 
 
 mean by a chemical composition of the hu- 
 a chemical analysis the solids and fluids of 
 
 first reduced to a number of compound sub- 
 are termed proximate principles. These 
 by an ultimate analysis, into fifteen chem- 
 
 The different chemical elements thus ob- 
 
 proportion in which they exist, are shown 
 
 table : * 
 
 . . 72.00] O H and C are found in all the tissues 
 . . 9 . 10 I and fluids of the body without excep- 
 
 |- tion. 
 . . 2 .50 O H C and N found in most of the 
 • • I 3-5°J fluids of the tissues except fats. 
 . . : 14.7 In fibrin, casein, albumin, gelatine, as 
 potassium sulpho-cyanide in saliva ; 
 as alkaline-sulphate in urine and sweat. 
 . . 1 .15 In fibrin and albumin ; in brain, as tri- 
 sodium ; phosphate in blood and sa- 
 liva, etc. 
 . . 1 .30 As calcium phosphate in lymph, chyle, 
 blood, saliva, bones and teeth. 
 ;.io As chloride sodium in all the fluids and 
 i solids of the body except enamel ; as 
 
 sodium sulphate and phosphate in 
 blood and muscles. 
 As potassium chloride in muscles ; gen- 
 erally found with sodium, as sulphates 
 and phosphates. 
 :.ooi Generally in association with calcium, 
 
 as phosphates in bones. 
 1.085 I n combination with sodium, potas- 
 sium and other bases, in all the fluids 
 and solids. 
 ;.o8 As calcium fluoride in bones, teeth and 
 
 urine. 
 Loi In blood globules, as peroxide in mus- 
 cles, 
 traces In blood, bones and hair. 
 traces Probably in hair, bones and nails. 
 
CHEMICAX COMPOSITION OF THE HUMAN BODY. 1 5 
 
 Summary. Of the four chief elements which combined 
 make up 97 per cent, of the body, O H N are eminently 
 mobile, elastic, and possesses great atomic heat. C H N 
 are distinguished for the narrow range and feebleness of 
 their affinities and chemical inertia. C has the greatest 
 atomic cohesion. O is noted for the number and intensity 
 of its combinations, and its remarkable display of chemical 
 affinity, combining with every element except fluorine. 
 
 With the exception of the gases O H and N, what cari 
 you say ? Other elements do not exist alone in the body, 
 but are combined in characteristic proportions to form com- 
 pounds, the proximate principles, the ultimate compounds 
 to which the fluids and solids can be reduced. 
 
 How do proximate principles exist in the body ? Under 
 their own form and can be extracted without losing their 
 distinctive properties. 
 
 How are proximate principles divided ? There are about 
 one hundred proximate principles, which are divided into 
 four classes, viz : inorganic, organic non-nitroge7iized, organic 
 nitrogenized and principles of waste. 
 
 I. INORGANIC PROXIMATE PRINCIPLES. 
 
 Although this subject is treated elsewhere, give a brief 
 outline of those four classes of proximate principles ? 
 
 1. Inorganic proximate principles are oxygen, found in 
 lungs and blood. Hydrogen, in stomach and intestines. 
 Nitrogen, in blood and intestines. Carbonic anhydride, 
 found in expired air of lungs. Carburetted hydrogen and sul- 
 phuretted hydrogen found in lungs and intestines. Water, 
 in all the solids and fluids. Sodium chloride, found in all 
 the solids and fluids except the enamel of the teeth. Potas- 
 sium chloride, in muscles, liver, saliva, gastric juice, etc. 
 Ammonium chloride, gastric juice, saliva, tears, urine. Cal- 
 cium chloride, bones, teeth and urine. Calcium carbonate, 
 
1 6 COMPEND OF HUMAN PHYSIOLOGY. 
 
 bones, teeth, cartilage, internal ear and blood. Calcium 
 phosphate, magnesium phosphate, sodium phosphate, potas- 
 sium phosphate, found in all fluids and solids of the body. 
 Sodium sulphate, potassium sulphate, universal except milk, 
 bile, and gastric juice. Sodium carbonate, potassium car- 
 bonate, bones, blood, urine, lymph, etc. 
 
 Of this class which most important? Oxygen is one of 
 the constituents of all the fluids and solids of the body ; it 
 is found in a free state in the respiratory passage and intes- 
 tinal tract. The function of O in the body appears to be 
 the oxidation of the albuminous, oleaginous, and saccha- 
 rine compounds to their ultimate forms, urea, carbonic acid, 
 water, etc. 
 
 As to whether this is brought about by direct oxidation 
 or by a fermentative process is yet unknown. As O only 
 enters into combination under a high temperature, it is 
 assumed that it exists in the body under the form of ozone, 
 OO 3 , which possesses remarkably active oxidizing powers. 
 
 What can you say of hydrogen? It is also a constituent 
 element of almost all the compounds of the body ; existing 
 in a free state in the intestinal tract, when it is produced by 
 a decomposition of organic substances. 
 
 What is the function of hydrogen ? Its function in the 
 system is unknown, yet it is asserted by Hoppe-Seyler that 
 hydrogen unites with neutral oxygen, 2 , in the tissues, 
 forming water and liberating oxygen in the nascent state, 
 which becomes the oxidizing agent. The process is repre- 
 sented in the following equation : H H -j- O. -f n = H 2 O + 
 On, in which n represents the oxidizing substance. 
 
 To combine 2 and H what have you ? The combination 
 form water, which is the most essential constituent of the 
 body. 
 
 How much of the body is composed of water ? About 
 seventy per cent, of the entire body weight. 
 
CHEMICAL COMPOSITION OF THE HUMAN BODY. 17 
 
 Its most important function ? A vehicle, lubricant, solv- 
 ent, etc. 
 
 How introduced into the body? In the form of drink, 
 and as a constituent of all kinds of food. The average 
 quantity consumed daily is about four pints. 
 
 How does water act as a solvent, etc. ? Gives general 
 pliability to various tissues, and promotes the passage of 
 inorganic and organic matter through animal membranes. 
 It also promotes chemical changes which are essential to 
 absorption and assimilation of food and the elimination of 
 products of waste. 
 
 How eliminated ? By the skin, lungs and kidneys. 
 
 What can you say of sodium chloride ? It is present in 
 all the solids and fluids of the body, with the exception of 
 the enamel of the teeth, regulates osmotic action, holds the 
 albuminous principles of the blood in solution, and pre- 
 serves the form and consistence of blood corpuscles and the 
 cellular elements of the tissues by regulating the amount 
 of water entering into their composition. 
 
 How is chloride sodium introduced ? In the form of 
 nearly all foods and drinks, each person containing four or 
 five ounces ; of this, about ten per cent, is consumed and 
 eliminated daily — thrown off chiefly by skin and kidneys. 
 
 "What part does calcium-phosphate play in the body ? 
 Most abundant of all the inorganic principles, with the 
 exception of water, and is present to a great extent in 
 bone, teeth, muscles and milk. It gives the requisite con- 
 sistency and solidity to the different organs, and in the 
 blood it is held in solution by the albuminous constituents. 
 The sodium and potassium phosphates are present in most of 
 the solids and fluids, and give to them their alkaline reac- 
 tion. They are chiefly derived from the food. 
 
l8 COMPEND OF HUMAN PHYSIOLOGY. 
 
 2. ORGANIC NON-NITROGENIZED PRINCIPLES. 
 
 From what are Organic Non-nitrogenized Principles 
 derived? Derived mainly from the vegetable world, but 
 are also produced within animal body. 
 
 Into how many classes can you define this second class 
 of proximate principles ? Into four subdivisions, (i) The 
 carbo-hydrates \ comprising starch and sugar, bodies in which 
 the O and H exist in proportion to form water ; (2) The fats, 
 bodies having the same elements entering into their compo- 
 sition, but with the carbon and hydrogen increased and the 
 oxygen diminished in amount ; (3) Fatty acids, which com- 
 bine with sodium, potassium, and calcium, are found as salts 
 in various fluids of the body, such as blood, chyle, faeces, etc. 
 (4) Alcohols. In this group we have Glycerine, Cholesterin, 
 and Alcohol. Glycerine is chemically a triatomic alcohol in 
 combination with the neutral fats of the body. During pan- 
 creatic digestion it is set free. This by many physiologists 
 is supposed to be directly concerned in the production of 
 glycogen. Cholesterin is a crystallizable substance largely 
 present in the bile, though it is found in other fluids and 
 solids. Alcohol has been found in the urine. It is supposed 
 to be the result of an alcoholic fermentation in the intes- 
 tines. 
 
 3. ORGANIC NITROGENIZED PRINCIPLES. 
 
 Give a brief outline of this third class? This class 
 are organic in their origin, being derived from the animal 
 and vegetable world. They are taken into the body as food, 
 and are appropriated by the tissues, and constitute their 
 organic basis. They differ from the non-nitrogenized sub- 
 stances in not being crystalline, but amorphous, in having 
 a more complex but just as definite composition, and con- 
 taining in addition to C HO, nitrogen, with at times, 
 sulphur and phosphorus. 
 
CHEMICAL COMPOSITION OK THE HUMAN BODY. 19 
 
 The proteids possess peculiarities which distinguish them 
 from all other substances, viz., a molecular mobility, which 
 permits isomeric modifications to take place with great fa- 
 cility; a catalytic influence, in virtue of which they promote, 
 under favorable conditions, chemical changes in other sub- 
 stances ; e. g.y during digestion salivin and pepsin cause 
 starch and albumin to be transformed into sugar and albu- 
 rn inose respectively. 
 
 Briefly outline the principal nitrogenized (or proteid 
 compounds) bodies as found in the organism ? They are 
 quite numerous, and although they resemble each other 
 in many particulars, yet there are important distinctions, 
 and can be better understood in the following groups : 
 
 1. Native Albumins. — Proteid bodies soluble in -water y 
 many acids, and usually in alkalies ; coagulable at a temper- 
 ature of from 140 to 163 F. 
 
 a. Serum Albumin, the principal form of albumin found 
 in the animal fluids and solids. 
 
 b. Egg Albumin, not found in ordinary tissues, but pres- 
 ent in white of egg. 
 
 2. Globulins. — Proteid bodies insoluble in water, but 
 soluble in solutions of sodium chloride. 
 
 a. Globulin, found in many tissues, but largely present in 
 crystalline lens. 
 
 b. Myosin, found in the muscles in life, in a fluid condi- 
 tion ; after death it undergoes coagulation, giving rise to 
 the rigidity of the muscles. 
 
 c. Paraglobulin, present in blood and obtained from it by 
 passing a stream of carbon dioxide through it ; it is also pre- 
 cipitated by adding sodium chloride. 
 
 d. Fibrinogin, present in serous fluids and blood, and can 
 be precipitated by the prolonged use of carbon dioxide ; it 
 is also precipitated by the addition of 12 or 16 per cent, of 
 sodium chloride. 
 
20 COMPEND OF HUMAN PHYSIOLOGY. 
 
 3. Derived Albumins. — Proteid bodies which are not 
 coagulable by heat ; insoluble in pure water and in salt 
 solutions ; soluble in both acid and alkaline solutions. 
 
 a. Acid Albumin, found principally in stomachs during 
 the first stage of digestion, the result of the action of the 
 hydrochloric acid upon the albumin of the food. 
 
 b. Alkali Albumin, found in the intestine during pancre- 
 atic digestion, the result of the action of alkalies upon the 
 albumin of the food. 
 
 c. Casein, the chief proteid of milk; it is precipitated by 
 acetic acid and rennet. 
 
 4. Peptones. — These bodies are found in the stomach 
 and intestinal tract by the action of the gastric and pancre- 
 atic juices upon the albumins of the food. Soluble in water, 
 alkaline and acid solutions ; non-coagulable by heat ; very 
 diffusible. They are precipitated by tannic acid and alcohol. 
 
 5. Albuminoids. — The albuminoids are the result of Ya- 
 rious modifications of albumins occurring during the nutri- 
 tive process, as well as by the action of various external influ- 
 ences. 
 
 a. Mucin, the characteristic ingredient of mucus, secreted 
 by the mucous membrane, giving to it its viscidity. 
 
 b. Chondritis found in cartilage. 
 
 c. Gclati?i, found in connective tissue, tendons, ligaments, 
 bones, etc. 
 
 d. Elastin, found in elastic tissue. 
 
 e. Keratin, found in skin and epidermic appendages, nails, 
 hair, horn, etc. 
 
 6. Fibrin. — A filamentous albumin obtained by washing 
 blood clots. It is insoluble in water and mineral acids. 
 
 4. FOURTH CLASS OF PROXIMATE PRINCIPLES. 
 
 Under what head is this fourth class generally known ? 
 
 Principles of waste. 
 
STRUCTURAL COMPOSITION OF THE BODY. 21 
 
 Known by what names ? Urates. 
 
 Name the principal elements of " Waste ? " The principal 
 
 elements of Waste are : 
 
 Urea, 
 Creatin, 
 Creatinin. 
 Cholesterin, 
 
 Those principles are represented as what ? Waste of or- 
 ganic origin, arising within the body as products of disassim- 
 ilation or retrograde metamorphosis of the tissues. They 
 are absorbed by the blood, carried to the various excretory 
 organs, and by them eliminated from the body. The ex- 
 crementitious substances will be fully considered under 
 Excretion. 
 
 Xantliin, 
 
 Sodium, 1 r-j 
 Potassium, [_ 2 
 
 Tvrosin, 
 
 Hippuric Acid, 
 
 Ammonium, [ % 
 
 Calcium Oxalate, 
 
 Calcium, J ? 
 
 CHAPTER III. 
 
 STRUCTURAL COMPOSITION OF THE BODY. 
 
 Give the proximate quantity of the chemical elements 
 and proximate principles of the body weighing 154 lbs. ? 
 Ans. This has been estimated as follows : 
 
 Lbs. Oz. 
 
 Oxygen in . . 
 
 Hydrogen 14 . . 
 
 Nitrogen 3 8 
 
 Carbon 21 . . 
 
 Calcium 2 . . 
 
 Phosphorus 1 12 
 
 Sodium, etc 12 
 
 154 • • 
 
 Lbs. Oz. 
 
 Water iit . . 
 
 Albuminoids 23 7 
 
 Fats 12 . . 
 
 Calcium Phosphate . . 5 13 
 
 " Carbonate . . 1 . 
 
 " Fluoride 3 
 
 Sodium Sulphate, etc. ... 9 
 
 154 • • 
 
22 COMPEND OF HUMAN PHYSIOLOGY 
 
 CHAPTER IV. 
 
 THE BLOOD. 
 
 What is the most abundant and highly organized fluid of 
 body Ans. Blood. 
 
 What does it contain ? All the elements necessary for 
 nutrition. 
 
 What does it receive ? Products of waste. 
 
 What do these processes require ? Regeneration of the 
 blood and elimination of effete matter. 
 
 What is extra vascular tissue ? That not directly sup- 
 plied with blood. 
 
 How nourished ? By imbibition. 
 
 What tissues are supplied by blood ? Those in which 
 nutrition is active. 
 
 Symptoms produced by abstracting large quantity of 
 blood ? Stops the vital powers. 
 
 Effect of returning the blood? Suddenly revives. 
 
 Why does death not occur immediately where large 
 artery is cut ? The hemorrhage weakens the heart. 
 
 What is transfusion ? Injecting blood of one person into 
 another. 
 
 Part inject? Red corpuscles. 
 
 Why? Vivifying power lies in them. 
 
 Amount? Three to six fluid ounces. 
 
 Dangers of transfusion? Shock to heart and danger of 
 getting air into veins. 
 
 Danger if air gets into veins? It can't circulate through 
 the pulmonary capillaries and causes death. 
 
 Danger if it gets into arteries? None. 
 
 What is blood ? Fluid found in the blood vessels. 
 
 Amount ? One- tenth weight of the bodv. 
 
THE BLOOD. 23 
 
 How determined ? Decapitate, drain the blood, then wash 
 blood vessels with water, evaporate this to a clot and com- 
 pare to other clot to see how much blood it would represent. 
 
 When greatest? During or just after digestion. 
 
 More blood in male or female ? Male. 
 
 At what period of life is there least blood, proportionately ? 
 Infancy. 
 
 What two elements make up blood? Plasma and cor- 
 puscles. 
 
 State the characters of blood ? Red, opaque fluid, saline 
 taste, alkaline in reaction, characteristic odor. 
 
 Why opaque ? Due to the difference of refractive power 
 between corpuscles and plasma. 
 
 Taste ? Saline. 
 
 Why ? Due to chloride of sodium. 
 
 Odor ? Characteristic of the animal. 
 
 How brought out? Add a mineral acid. 
 
 Reaction? Alkaline. 
 
 Why ? Due to the basic phosphates and carbonates. 
 
 Specific gravity? 1052 to 1057. 
 
 Greatest, male or female? Male. 
 
 Color in arteries ? Bright red. 
 
 Color in veins ? Blue. 
 
 When red in veins ? During the period of gland activity. 
 
 Why? Circulates too fast to give up its oxygen. 
 
 Warmest which side of the heart ? Right. 
 
 Why? Has not been cooled in going through the lungs 
 as that of left side. 
 
 Warmest, arteries or veins ? Arteries. 
 
 Hottest blood in the body ? That of the hepatic vein. 
 
 Temperature ? One hundred and seven degrees Fahrenheit. 
 
 Warmest in portal vein or abdominal aorta ? Portal vein. 
 
 Temperature of the blood? Ninety-eight and one-half 
 decrees. 
 
24 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Anatomical elements of the blood? Red and white cor- 
 puscles. 
 
 Define " anatomical element ? " Any thing that undergoes 
 waste and repair. 
 
 Proportion of red corpuscles to blood ? Little less than 
 one half. 
 
 More in male or female ? Male. 
 
 Shape of red corpuscle ? Biconcave circular disc. 
 
 Where thickest ? At the edge of vessels. 
 
 Consistence of red corpuscles ? Consistence of liver. 
 
 Why think they are elastic ? On account of the persistency 
 with which they keep their shape. 
 
 If blood does not coagulate, why do the red corpuscles go 
 to the bottom ? Due to their high specific gravity. 
 
 What is their specific gravity ? 1088 to 1 105. 
 
 What is that of plasma ? 1028. 
 
 Appearance of red corpuscles under the microscope? 
 Nucleated. 
 
 Why ? Can't focus the edge with the center. 
 
 Color of red corpuscles ? Amber. 
 
 Illustrate ? Dilute it with water. 
 
 What do you mean by Rouleaux ? Arrangement of the 
 red corpuscles like piles of coin. 
 
 Cause of this arrangement ? An adhesive exudation. 
 
 Size of red corpuscle ? One thirty-five hundreths of an 
 inch. 
 
 Largest in which animal? Elephant and sloth. 
 
 Different shape in what animals ? Camel and llama. 
 
 How tell blood of man from lower animals ? By their 
 size. 
 
 Relation of muscular activity to the size of the corpus- 
 cle ? Inverse. 
 
 Peculiarity of red corpuscles of invertebratas ? Are oval 
 and have a nucleus. 
 
THE BLOOD. 25 
 
 How count red corpuscles ? Dilute blood and put in glass 
 tube. 
 
 Number to one twenty-fifth of an inch ? Four million. 
 
 In what vessels most abundant ? Veins. 
 
 In what vein are they most abundant ? Splenic. 
 
 Least abundant? Hepatic. 
 
 What does this indicate ? That they are manufactured in 
 the spleen and destroyed in the liver. 
 
 Post mortem appearance? Shriveled and serrated. 
 
 How make them resume their original form ? Add fluid 
 with the same density as plasma. 
 
 What is the structure of red corpuscles ? Homogeneous. 
 
 Why do you think so ? A membrane has never been 
 demonstrated. 
 
 Name the first blood vessel ? Area vasculosa. 
 
 When does the blood become red ? When the foetus is 
 one-tenth inch in diameter. 
 
 When does corpuscle appear first in foetus ? About the 
 same time. 
 
 Relative size at first? Thirty to one hundred per cent, 
 larger than in adult. 
 
 Shape then ? Most circular ; some oval or globular. 
 
 Appearance red blood corpuscles under microscope? 
 Nucleated. 
 
 How long do they remain so ? Three or four months. 
 
 Give reason for thinking that they are not produced by 
 any special organ? They exist before any organ. 
 
 Why think they are not formed from leucocytes ? They 
 exist before the leucocytes. 
 
 Origin of first corpuscles ? They are generated de novo. 
 
 In adult what is their origin? Spleen, lymphatic gland 
 and red marrow of the bones. 
 
 Color of marrow of bones in foetus? Red. 
 
 Name ? Lymphoid. 
 
26 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Color of marrow in long bones of adult? Yellow. 
 
 Where find red ? Short bones. 
 
 Part spleen plays? Manufactures red corpuscles. 
 
 Part liver plays? Destroys them. 
 
 What becomes of coloring matter? Goes to form other 
 pigmentary matter. 
 
 Relation of ansemia to corpuscle forming function of 
 the marrow? It increases it. 
 
 Function of red corpuscles ? Carry oxygen. 
 
 What part of blood most necessary to life ? Red corpus- 
 cles. 
 
 Symptoms when all the arteries to a part are tied ? Loss 
 of function. 
 
 What is the oxygen absorbing capacity of the blood? 
 Ten to thirteen times as much as water. 
 
 On what does it depend ? On red corpuscles. 
 
 Other name for the white corpuscles ? Leucocytes. 
 
 Why have they this name in blood? Because they are 
 found elsewhere. 
 
 Where are leucocytes normally found? Blood, lymph, 
 chyle, cholestrum and vitreous humor. 
 
 Where pathologically found ? Pus and irritated mucous 
 membranes. 
 
 Shape ? Globular. 
 
 In what part of vessel does red corpuscle circulate? 
 Middle. 
 
 Where do the white circulate? Along the sides of 
 vessels. 
 
 Cause ? Their adhesive character. 
 
 Size of leucocytes? One-twenty-five hundredth inch. 
 
 In what fluid do you find them in greatest abundance ? 
 Pus. 
 
 What shape may they assume ? Polygonal or ovoid. 
 
 When do they increase in size ? When confined in tissue. 
 
THE BLOOD. 27 
 
 Number as compared with red corpuscles? One to 
 seven hundred and fifty or one thousand red. 
 
 Specific gravity ? Ten per eeut. 
 
 When do they first appear? In early foetal life. 
 
 Why think spleen has to do with their production ? Find 
 more in splenic vein than splenic artery. 
 
 Why in lymphatic glands ? More in blood going to than 
 coming" from the glands. 
 
 What is leucocythemia? Abnormal amount of leucocytes 
 in the blood. 
 
 What does leucocyte mean ? White body. 
 
 Origin of leucocytes? Spleen, marrow of the bones, and 
 lymphatic glands. 
 
 Anatomical changes in the spleen and lymphatic glands 
 in leucocythemia ? They become enlarged. 
 
 Functions of the leucocytes? Thought to aid in coagu- 
 lation of blood. 
 
 Other name for blood plaques ? Elementary corpuscles. 
 
 Shape ? Flat circular discs. 
 
 Structure? Homogeneous. 
 
 Size ? One-sixth that of the red corpuscle. 
 
 Color? Grayish tint. 
 
 Number ? One to twenty or thirty red corpuscles. 
 
 Where are they distinct? In the circulating blood. 
 
 When do they adhere ? When the blood is drawn. 
 
 Changes they undergo out of the body ? They become 
 ovoid or elongated. 
 
 Function of the plaques ? To form red corpuscles. 
 
 Composition of red corpuscles? Globulin, inorganic 
 salts and coloring matter. 
 
 Rich in what inorganic salts? Salts of potassa. 
 
 What is globulin ? Organic nitrogenous proximate prin- 
 ciple of the red corpuscle. 
 
 How extracted ? By adding chloride of sodium to defibri- 
 nated blood. 
 
28 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What is the coloring matter of red corpuscle ? Haema- 
 globin. 
 
 How obtained ? By percolating blood with ether. 
 
 Shape of the crystals ? Four sided prisms or rhomboids. 
 
 Color ? Purplish. 
 
 How is it precipitated ? By acetic acid, nitrate of mer- 
 cury, chlorine gas and ferrocyanide of potassium. 
 
 In what is it soluble ? Water and weak alkaline solutions. 
 
 Proportion of coloring matter in blood? One hundred 
 and twenty-seven parts per one thousand. 
 
 In dried corpuscles ? Twelve-thirteenths to nine-tenths 
 of the dried corpuscle. 
 
 With what does coloring matter unite? With oxygen. 
 
 What kind of union ? Unstaple. 
 
 What is plasma ? Watery element of the blood. 
 
 Specific gravity of it? 1028. 
 
 In studying the analysis of the blood how is it divided ? 
 Into proximate principle or chemical constituent. 
 
 Define chemical constituent ? Something that exists as 
 such in the body, and when extracted and decomposed 
 changes properties. 
 
 Is it an element or compound ? May be either. 
 
 Define an element ? Simple and uudecomposable sub- 
 stance. 
 
 Name one ? Oxygen. 
 
 Define a compound ? Substance made up of two or more 
 elements. 
 
 Name one ? Water. 
 
 What is the first class of chemical constituents? Inor- 
 ganic. 
 
 What are the properties of the inorganic ? Inorganic in 
 origin, definite chemical composition, crystallizable, need no 
 preparation for introduction, undergo no change in the organ- 
 ism, and always exist in combination with organic. 
 
THE BLOOD. 29 
 
 When is there a deficiency of elimination ? Old age. 
 
 What does it cause ? Calcareous degeneration. 
 
 Most important of the inorganic ? Water. 
 
 Where do you find it? Throughout the system. 
 
 How do you know when you need it ? Get thirsty. 
 
 Where thirst referred ? Throat and fauces. 
 
 Where exist ? In the tissues. 
 
 Amount of chloride of sodium, or common salt, in the 
 blood ? Four parts per 1000, or about five and one-half 
 ounces in each person. 
 
 Function of chloride of sodium ? It gives density to the 
 plasma, aids in osmosis and determines transudation. 
 
 Amount of inorganic salts ? Six to eight parts per 1000. 
 
 Function of them ? Prevent solution of the corpuscle. 
 
 Which of them are decomposed in the system ? Carbon- 
 ates and phosphates. 
 
 Which are formed in the system ? Organic salines. 
 
 Function of pneumic acid ? To decompose the carbonates 
 and bicarbonates. 
 
 Origin of pneumic acid ? Formed in the organism. 
 
 Origin of lactic acid ? From decomposition of lactose. 
 
 Function? Same as pneumic acid. 
 
 Name the organic salines ? Lactates and pneumates. 
 
 Origin ? Action of lactic and pneumic acid on the bases. 
 
 Name the organic non-nitrogenized constituents of the 
 blood ? Olein, margarin, steirine, lecithin, glucose, glyco- 
 genic matter and inosit. 
 
 Why is lecithin placed in this group ? It has many of 
 the properties of the fats. 
 
 Where found? Blood, bile, nervous tissue, and yolk of 
 
 egg- 
 
 What organ first produces sugar ? Placenta. 
 
 After birth in what blood find it ? Blood going from liver 
 to lungs.. 
 
30 COMPEND OF HUMAN I'll YSIOLOGY. 
 
 What becomes of it ? It is destroyed in the lungs. 
 
 Is it ever deposited ? It is not. 
 
 Is it ever eliminated ? Only where large quantity is in- 
 gested. 
 
 Function of sugar? Thought to produce fat. 
 
 How are fats and sugars distinguished from the others ? 
 They contain carbon, oxygen and hydrogen. 
 
 How are fats introduced ? Form of adipose tissue. 
 
 Where digested and by what ? In small gut by the pan- 
 creatic juice. 
 
 By what is it absorbed ? Lacteals. 
 
 Destination of fats? Either destroyed or deposited. 
 
 Ever eliminated ? No. 
 
 Function? Thought to keep up animal heat. 
 
 Name the organic nitrogenized principles of blood. 
 Plasmine, serine, peptones and coloring matter. 
 
 Properties of this class? Organic in origin, have no defi- 
 nite chemical composition, are not crystallizable, need prepa- 
 ration for introduction and undergo change in the organism. 
 
 What is plasma ? Watery element of blood. 
 
 What is plasmine ? Organic nitrogenous proximate prin- 
 ciple of blood. 
 
 Amount? Twenty-five parts per one thousand. 
 
 How obtained? By adding saturated solution of chloride 
 of sodium to plasma. 
 
 How decompose it? Add water and whip with twigs. 
 
 What are the products of its decomposition ? Metalbu- 
 min and fibrin. 
 
 How many parts of each ? Metalbumiu twenty-two parts, 
 fibrin three parts. 
 
 Is fibrin a proximate principle ? No. 
 
 What is it ? A product of decomposition of plasmine. 
 
 What is metalbumin^ Also a product of decomposition 
 of plasmine. 
 
THE BLOOD. 31 
 
 What is serine? Organic nitrogenous proximate princi- 
 ple of blood. 
 
 How does it differ from albumin? It is more osmotic and 
 is not coagulated by ether. 
 
 Amount of serine ? Fifty-three parts per one thousand. 
 
 What represents the albumin of the older writers? Met- 
 albnmin and serine. 
 
 Does the blood contain albumin ? It does not. 
 
 What are peptones? Organic nitrogenous proximate prin- 
 ciples of blood. 
 
 Origin ? Products of stomachic digestion. 
 
 Has the coloring matter ever been isolated ? No. 
 
 What are paraglobine and fibrinogen ? Fibrin producing 
 principles. 
 
 In what form is blood in the vessels ? Fluid. 
 
 How if circulation is disturbed? Clots. 
 
 Technical name for a clot ? Crassamentum. 
 
 What blood coagulates most rapidly? That of birds. 
 
 WTiy will arterial blood coagulate more rapidly than 
 venous? There is more fibrin formed. 
 
 What is the first thing you notice in the process of coag- 
 ulation ? A thin pellicle forms on top. 
 
 In what time ? One to six minutes. 
 
 Next thing ? It gets gelatinous on the sides. 
 
 In what time ? Two to seven minutes. 
 
 Next thing ? Entire mass becomes gelatinous. 
 
 In what time ? Seven to sixteen minutes. 
 
 What becomes of the clot? It separates into two parts. 
 
 Cause? Contraction of the fibrin. 
 
 In what time ? Ten to twelve hours. 
 
 What does the solid part contain? Corpuscles and fibrin. 
 
 What does the serum contain ? The watery part. 
 
 Amounts of each ? About equal. 
 
 On what does the consistence of clot depend? On the 
 rapidity of coagulation. 
 
32 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Color of a venous clot ? Blue. 
 
 Changes when exposed to air? Becomes red at the edge. 
 
 Why? It takes on oxygen. 
 
 What do you mean by " buff y coat ?" Yellow layer on 
 top of the clot. 
 
 Cause of the yellow color? A peculiar coloring matter 
 which has never been isolated. 
 
 Cause of bufify coat ? Slow coagulation. 
 
 Old significance of it? Thought it was pathognomonic of 
 inflammation. 
 
 What is serum ? Watery part of the clot. 
 
 What is plasma? Watery part of the blood. 
 
 Which is physiological ? Plasma. 
 
 Color of serum ? Straw color. 
 
 Specific gravity? 1028. 
 
 To what is the coagulation of blood due ? Formation of 
 fibrin. 
 
 What expresses the serum ? Contraction of the fibrin. 
 
 When do the corpuscles remain in the clot ? Due to the 
 adhesive matter which covers them. 
 
 What kind of stream does blood coagulate more rapidly ? 
 Slow and small stream. 
 
 What kind of vessel would hasten coagulation ? A rough 
 one. 
 
 How can you produce instantaneous coagulation ? Re- 
 ceive the blood on a cloth. 
 
 Influence of air on coagulation ? It favors it. 
 
 Influence of a vacuum ? Increases it. 
 
 Effect of freezing the blood ? Retards coagulation while 
 it is frozen. 
 
 What chemicals will prevent coagulation ? Soda and 
 potash salts. 
 
 Why does menstrual flow not coagulate ? Vaginal secre- 
 tion keeps it fluid. 
 
THE BLOOD. 33 
 
 Does blood coagulate in vessels after death ? Yes. 
 
 In what time ? Twelve to twenty-four hours. 
 
 Chiefly in what vessels ? The veins. 
 
 Why are arteries empty ? They contract after death. 
 
 Coagula are largest on which side of the heart ? Right 
 side". 
 
 Does coagula form during life ? Yes. 
 
 What were they called by the old writers ? Polypi. 
 
 How do they occur? When death is gradual. 
 
 How can you tell anti from a post-mortem clot ? Ante- 
 mortem is firmer, whiter, and more closely adherent. 
 
 Effect of proj ections in the vessel ? Favors their formation . 
 
 Name of stationary clot ? Thrombus. 
 
 Of a floating one ? Embolus. 
 
 Condition the blood assumes when effused in tissue or 
 cavities ? It coagulates. 
 
 In what cavity will it remain fluid ? Tunica vaginalis. 
 
 What is hemorrhagic diathesis ? A tendency to bleed. 
 
 Cause? Lack of fibrin-producing principle. 
 
 Why will a cut vessel bleed more than a torn one ? The 
 torn one exposes more blood to the air, favoring coagulation. 
 
 Office of coagulation? To arrest haemorrhage. 
 
 Cause of coagulation ? Decomposition of plasmine by a 
 ferment. 
 
 Origin of the ferment ? Due to changes in the leucocytes. 
 
 Do the red corpuscles play any part in coagulation? No. 
 
 What is paraglobin? About the same as metalbumin. 
 
 Peculiarity of the blood of a leech bite ? It bleeds consid- 
 erably and remains fluid. 
 
 What blood does not coagulate very readily after death ? 
 That of renal and hepatic veins and capillary blood. 
 
 Is fibrin a proximate principle ? No ; it is a product of 
 decomposition of plasmine. 
 
34 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER V. 
 
 THE HEART. 
 
 Where do you find it? Ans. Thoracic cavity in middle 
 mediastinum. 
 
 Peculiarities of its fibres ? Small, striated and anastomose 
 freely, haYe no sarcolemma, and contain granular matter. 
 
 Give arrangement of muscular fibres ? Two layers ; the 
 external is oblique and the internal circular. 
 
 Origin of external ? At base of heart. 
 
 Where become spiral ? At apex. 
 
 Where go ? To form the columna carneae. 
 
 Describe the different kinds? (i) Columna carneae proper, 
 simply fleshy projections in the heart ; (2) Columna papilla- 
 ria, give attachment to the cordae tendinae ; (3) trabeculae 
 carnae, are attached at each end and free in the middle. 
 
 Thickness of right auricle ? One line. 
 
 Left auricle ? One and one-half lines. 
 
 Hight ventricle ? Two and one-half lines. 
 
 Left ventricle ? Seven lines. 
 
 What is systole ? Contraction of the heart. 
 
 What is diastole ? Dilatation of the heart. 
 
 To what part are these terms referred ? To the ven- 
 tricles. 
 
 Why ? They are most important to the circulation. 
 
 When are the auricles not receiving blood ? During au- 
 ricular systole. 
 
 From auricles where does the blood go ? To ventricles. 
 
 Effect this has on the ventricles ? Dilates them. 
 
 What follows ? The ventricles contract. 
 
 From right ventricle where does the blood go ? Through 
 pulmonary artery to lungs. 
 
THE HEART. 35 
 
 From left ventricle where does it go? Through the aorta 
 to general system. 
 
 What are the movements of the heart ? Forward, upward 
 and from left to right. 
 
 Why does it raise up ? Because the anterior fibres are 
 longer than the posterior. 
 
 Why come forward ? Due to distention of the great 
 vessels. 
 
 Why go from left to right ? Because the fibres run from 
 right to left. 
 
 What part of the heart is fixed ? Base. 
 
 What is the origin of a muscle ? A fixed point. 
 
 Why does the heart twist ? On account of the spiral 
 course^ of the superficial fibres. 
 
 Why does it get hard? Due to muscular contraction. 
 
 Does it shorten or elongate ? It shortens. 
 
 What was the old idea ? That it elongated. 
 
 How was it determined ? Pin the base to a board and 
 measure it. 
 
 What is the impulse of the heart ? Beat against the chest 
 wall. 
 
 When does it occur? During systole. 
 
 Proof? If you introduce your finger into the chest you 
 feel it at the same time as pulse. 
 
 What represents time ? One. 
 
 Time of auricular systole? One-fifth. 
 
 How was it determined? By means of the cardio-graph. 
 
 Describe the contraction. Feeble contraction followed 
 immediately by relaxation. 
 
 Time of ventricular systole ? Two-fifths. 
 
 Describe it. Powerful contraction followed by sudden re- 
 laxation. 
 
 What time do the ventricles rest in a day? ^hree-fifths. 
 
 Time auricles rest? Four-fifths. 
 
36 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Time of ventricular systole ? Two-fifths. 
 
 What is the force of the heart? Fifty-one and one half 
 pounds. 
 
 How determined ? Multiply area of left ventricle by ar- 
 terial pressure. 
 
 Are there any valves in the right auricle ? Yes. 
 
 Describe them. Coronary guards, opening of coronary 
 vein and Eustachian extend between foramen ovale and the 
 auriculo-ventricular opening. 
 
 Do they assist in circulation ? Not in an adult. 
 
 What causes the blood to go from right auricle to ven- 
 tricles ? Force from behind and opening in front, and con- 
 traction of the auricle. 
 
 Functions of auriculo-ventricular valves? To prevent 
 regurgitation into auricle during systole. 
 
 When are they closed ? During systole. 
 
 What is the heart doing then ? Emptying its contents. 
 
 What valves are then open ? Semilunar. 
 
 Function of the semilunar valves ? Prevent reflux of 
 blood into ventricles. 
 
 When are they closed ? During diastole. 
 
 What is the heart then doing ? Filling. 
 
 State the appreciable phenomena of the heart? Pulse, 
 impulse and sound. 
 
 In studying the rhythm of heart, where begin ? Auricu- 
 lar systole. 
 
 Why? There is where the blood first gets in. 
 
 Studying rhythm of sounds, where begin ? Ventricular 
 systole. 
 
 Why? It is heard first. 
 
 Name the sounds of the heart? First and second. 
 
 Why call the long one the first sound ? It is heard first. 
 
 Which sound is simple ? Second. 
 
 Cause of second sound ? Closure of the semilunar valves. 
 
THE HEART. 37 
 
 How prove it? Tie them back and you will not hear the 
 sound. 
 
 What elements make up the first sound ? Valvular, pro- 
 longed and booming. 
 
 What is the cause of the booming element ? Beat against 
 the chest wall- 
 Cause of prolonged ? Contraction of the heart muscle. 
 
 Cause of valvular? Closure of the auriculo-ventricular 
 valves. 
 
 How make the first sound like the second ? Put the pa- 
 tient on his back and towel on chest. 
 
 What are the causes of the first sound ? Beat against the 
 chest wall, muscular contraction and closure of the auriculo- 
 ventricular valve. 
 
 Where heard loudest? At the apex and left side. 
 
 Why? Transmitted to chest by apex beat. 
 
 Condition of the heart then ? Emptying. 
 
 Course of the blood during the first sound ? Into the ar- 
 teries. 
 
 What keeps the blood from going back into auricles? 
 The auriculo-ventricular valves. 
 
 On which side of the heart may the valves be diseased ? 
 Left. 
 
 Abnormal sounds caused by disease of the mitral valves 
 are heard where ? Apex and left side. 
 
 When? Just before or during systole. 
 
 Condition of ventricle just before hear first sound ? It is 
 filled. 
 , Blood flowing from auricle into what? Ventricle. 
 
 Does it usually cause a sound ? No. 
 
 Why not ? The opening is sufficiently large for blood to 
 pass without transmitting noise. 
 
 What would obstruct the flow from auricle to ventricle ? 
 Where valves are tied and can't open. 
 
38 ' COMPEND OF HUMAN PHYSIOLOGY. 
 
 Would it then cause a sound ? Yes. 
 
 Why? Blood is being forced through small opening. 
 
 Where do you hear it? Apex and left side. 
 
 When ? Just before systole. 
 
 What is the heart doing ? Filling. 
 
 Cause of this sound ? Blood being forced through a small 
 opening. 
 
 What is it called ? Presystolic. 
 
 Why? Because it is heard just before systole. 
 
 The condition of the valves is called what? Mitral ste- 
 nosis. 
 
 Why? Because the opening is made small. 
 
 What is the condition of the heart during the first sound ? 
 Emptying. 
 
 Course of the blood ? Into the arteries. 
 
 If mitral valves do not close sufficiently what is the di- 
 rection of the blood ? Both directions. 
 
 Effect of this on first sound ? Masks it. 
 
 This condition of valves is called what? Mitral insuffi- 
 ciency. 
 
 What is the sound called ? Mitral regurgitation. 
 
 Where heard ? Apex and left side. 
 
 When ? When you feel the pulse ? 
 
 Direction of the blood when you hear it? Into arteries. 
 
 If heart is beating rapidly, how tell the second from the 
 first sound ? By the position you hear it. 
 
 If you hear an abnormal sound at apex just before you 
 feel the pulse, what is it called ? Presystolic. 
 
 Cause of it? Mitral stenosis. 
 
 When you feel the pulse ? Mitral regurgitation. 
 
 Name ? A systolic brew. 
 
 Cause ? Blood flowing back into auricle. 
 
 Where do you hear the second sound loudest ? Base and 
 right side. 
 
THE HEART. 39 
 
 Why? It is conducted along the great vessels. 
 
 Cause of the second sound ? Closure of semilunar valves. 
 
 Does blood cause sound normally in passing through the 
 semilunar valves ? Xo. 
 
 When would it do so ? Where valves tied and can't open. 
 
 Why? Blood is forced through small opening. 
 
 Where do you hear it? Base and right side. 
 
 When ? As you feel the pulse. 
 
 What is it called ? Aortic stenosis. 
 
 Condition of heart when you hear it? Emptying. 
 
 Function of the semilunar valves ? To guard the arte- 
 ries. 
 
 If they don't close the opening, where does the blood 
 go ? Back into ventricle. 
 
 Effect of this on the second sound ? Masks it. 
 
 What would you have ? An abnormal sound. 
 
 Where do you hear it ? Base and right side. 
 
 When ? When you don't feel the pulse. 
 
 What is it called ? Aortic regurgitation. 
 
 Why? Because the blood is flowing back. 
 
 Condition of the heart when you hear it? Filling. 
 
 Frequency of the heart's action ? Seventy-two beats per 
 minute. 
 
 Period of life most frequent? At birth. 
 
 Frequency at that time ? One. hundred and twenty-six to 
 one hundred and forty per minute. 
 
 How frequent in adult male ? Seventy. 
 
 Adult female ? Seventy-six to seventy-eight. 
 
 Effect of old age ? Increases it. 
 
 Relation of heart's action to respiration? Direct relation. 
 
 Kind of pulse have in asphyxia ? Slow and strong. 
 
 Why? Gets so to overcome the obstruction in the sys- 
 temic capillaries. 
 
 How is arterial pressure then ? Very high. 
 
40 COMPEND OF HUMAN PHYSIOLOGY. 
 
 If the obstruction is not overcome, how will the heart 
 die ? Distention of the heart and paralysis of its muscular 
 fibres. 
 
 Name the different kinds of muscular fibres. Striated 
 and non-striated. 
 
 To what class does the heart belong? Striated. 
 
 How differ from the other striated? It is involuntary. 
 
 Things necessary for striated muscle to contract? Must 
 receive a stimulus. 
 
 What is the normal stimulus ? Nerve force . 
 
 If nerve is cut, what effect has it on muscle ? Muscle be- 
 comes paralyzed. 
 
 How does the heart differ from other muscles ? It needs 
 no stimulus. 
 
 How is contraction of heart influenced by circulation of 
 blood through it? Causes regular and powerful contraction. 
 
 Give illustration. Cut out the heart and pass liquid of 
 same density as blood through it, it will contract. 
 
 On what does the intermittent action and successive 
 action of the heart depend? Its contained sympathetic 
 ganglia. 
 
 Where situated ? In the heart substance at the base. 
 
 Proof? Remove the heart and cut it transversely, and the 
 apex will cease to beat. 
 
 Where find the ganglion of Remak? At expansion of 
 the inferior vena cava. 
 
 Ganglion of Bidder ? Between the left auricle and ven- 
 tricle. 
 
 Function of these two ? Motor. 
 
 Where find ganglion of Ludwig ? Between the two auri- 
 cles. 
 
 Function? Inhibitor ganglion. 
 
 Where does contraction of the heart start? At the gan- 
 glia. 
 
THE HEART. 41 
 
 What part of the heart has the power of intermittent 
 and regular contraction ? Muscular fibres of auricles and 
 upper third of ventricles. 
 
 Which surface of heart is most excitable ? Interior. 
 
 What is the natural stimulus to the heart? Passage of 
 blood through its cavity. 
 
 How is heart's action influenced by destruction of the 
 cardiac plexus ? Heart's action is immediately arrested. 
 
 Effect on heart by cutting the sympathetic ? Lessens the 
 cardiac movements. 
 
 Stimulating it? Increases its movements. 
 
 Name the inhibitory nerve. Pneumogastric. 
 
 Effect on heart if cut? Beats faster. 
 
 If stimulated ? Beats slower. 
 
 From what nerve does this action come ? Spinal acces- 
 sory. 
 
 Action of digitalis on the heart? Slows and strengthens 
 it. 
 
 How ? It stimulates the pneumogastric nerve. 
 
 Does it influence the heart if the pneumogastric is cut? 
 No. 
 
 Is the action of the pneumogastric nerve direct or reflex ? 
 Direct. 
 
 What do you mean by direct? Where the force origin- 
 ates in the center. 
 
 What mean by reflex ? Force sent back. 
 
 Does reflex inhibition ever occur? Yes. 
 
 Give illustration ? Tap the intestines of a frog and his 
 heart stops. 
 
 Cause of syncope ? Stimulus sent to the inhibitory center 
 in the medulla and then back to the heart. 
 
 Treatment? Swing the patient by the feet to stimulate 
 the center. 
 
42 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER VI. 
 
 FOETAL CIRCULATION. 
 
 Where do you begin to trace it? Placenta. 
 
 Through what vessel does it get to the child ? Umbilical 
 vein. 
 
 Carries what kind of blood ? Arterial. 
 
 Where does it enter the abdomen of child ? At the um- 
 bilicus. 
 
 It goes to what organ ? Liver. 
 
 What vein does it meet? Portal vein. 
 
 Greater part is distributed to what? Liver. 
 
 Does it all pass to the liver? No. 
 
 Blood that does not, goes where? Into inferior vena 
 cava. 
 
 How? Through the ductus venosis. 
 
 Where does the inferior vena cava empty? Right auri- 
 cle. 
 
 What part of the right auricle? Posterior and inferior 
 aspect. 
 
 The current is directed toward what opening ? Foramen 
 ovale. 
 
 What keeps the blood from going into right ventricle ? 
 Eustachian valve. 
 
 Give the attachment of the Eustachian valve. From the 
 foramen ovale to the auriculo-ventricular opening. 
 
 When is it largest? At birth. 
 
 How does blood get from right to left auricle ? Through 
 the foramen ovale. 
 
 Where does it go from left auricle ? To left ventricle. 
 
 Where does it go from left ventricle ? Into aorta. 
 
FCETAL CIRCULATION. 43 
 
 From aorta ? To the tissues. 
 
 Does it all pass to the upper extremity? No. 
 
 How is the blood returned from the upper extremity ? 
 By the superior vena cava. 
 
 How does this empty into right auricle ? Upper and pos- 
 terior part. 
 
 Direction of the current? Toward the auriculo-ventricu- 
 lar opening. 
 
 Where does blood go from right auricle ? To right ven- 
 tricle. 
 
 From right ventricle ? Pulmonary artery. 
 
 From pulmonary artery ? To lungs and to aorta. 
 
 How much passes to the lungs? Enough for nu- 
 trition. 
 
 Where do you find the ductus arteriosus ? Between the 
 pulmonary arterj- and aorta. 
 
 How does the blood get back to the placenta ? Through 
 the umbilical arteries. 
 
 Peculiarity of the internal iliac arteries in the foetus ? 
 Larger than in adult, and give off the umbilical. 
 
 How many cavities in the foetal heart? Two. 
 
 How are the auricles connected ? By foramen ovale. 
 
 How are the ventricles connected ? By the ductus arte- 
 riosus. 
 
 Peculiarity of foetal heart? Foramen ovale and Eusta- 
 chian valve. 
 
 Peculiarity of foetal arteries ? Have the ductus arteriosus 
 and umbilical. 
 
 Of foetal veins? Ductus venosis and umbilical vein. 
 
 Changes after birth ? Arteries and veins become obliter- 
 ated, foramen ovale closes and the Eustachian valve atro- 
 phies. 
 
 Why is the liver so large at birth ? It gets a large 
 amount of arterial blood. 
 
44 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Why is the head so large ? It also gets large amount. 
 
 Why are the lower extremities so small ? Get very little 
 arterial blood. 
 
 From which side does the membrane grow that closes 
 the foramen ovale ? Left. 
 
 When ? Tenth day after birth. 
 
 CHAPTER VII. 
 
 ARTERIES. 
 
 How many are there ? Two. 
 
 Name them. Aorta and pulmonary. 
 
 Why are they called arteries ? In olden times they were 
 thought to contain air. 
 
 Why thought to contain air ? They are found empty and 
 open after death. 
 
 Why are they found open ? Their thick walls hold them 
 open. 
 
 How does the pulmonary artery differ from the aorta in 
 its anatomy? Its walls are thinner and more distensible. 
 
 What is the course of arteries ? Direct. 
 
 Why? To get to the tissues with the least expenditure 
 of force. 
 
 How are arteries protected in the extremities ? By being 
 placed on the inside. 
 
 Where are they subject to pressure ? At the joints. 
 
 What arteries diminish in size ? Those that give off 
 branches. 
 
 Exception ? Abdominal aorta and vertebral arteries. 
 
 At what angle are arteries given off? At acute angles. 
 
 Exception ? The posterior intercostal arteries. 
 
ARTERIES. 45 
 
 At what angle are they given off ? Right angle. 
 
 Where do arteries anastomose freely? In the brain. 
 
 Why? To protect the brain. 
 
 How are arteries divided ? Large, medium, and small 
 arteries. 
 
 Name the large arteries. All those larger than the com- 
 mon iliacs and carotids. 
 
 Properties of large arteries ? Great strength and elas- 
 ticity. 
 
 Name the medium sized arteries. All between the large 
 and those one-twelfth to one-fifteenth inch in diameter. 
 
 Properties ? Considerable strength and elasticity, and 
 some contractibility. 
 
 Name the small arteries. All smaller than one-twelfth 
 to one-fifteenth inch in diameter. 
 
 Properties? Little strength and elasticity, and great con- 
 tractibilit3\ 
 
 Coats of arteries? External, middle and internal. 
 
 Which coat is the same in all arteries ? The internal. 
 
 Describe the external. White fibrous tissue. 
 
 Where does this coat cease ? Just before the capillary 
 system. 
 
 Function of outer coat? Strength. 
 
 Describe the internal coat. Simple homogeneous mem- 
 brane. 
 
 Function of internal coat ? To give a smooth surface for 
 the blood to pass. 
 
 What is the middle coat of large arteries made up of? 
 Yellow elastic tissue. 
 
 Are there any muscular fibres near the heart? No. 
 
 Why is the coat called " fenestrated membrane ?" It 
 has numerous foramina. 
 
 How does the middle coat change as you recede from 
 the heart? Losses in elastic tissue and gains in muscular. 
 
46 COMPEND OF HUMAN PHYSIOLOGY. 
 
 On which coat does the thickness of the artery depend ? 
 Middle coat. 
 
 What is the function of this coat? To giYe strength and 
 elasticity. 
 
 Where is it wholly muscular? In the arterioles. 
 
 What are arterioles ? The smallest arteries. 
 
 Describe their middle coat. A double layer of muscular 
 fibre. 
 
 Which coat of the arteries is supplied by blood vessels ? 
 External. 
 
 What are they called ? Vas vasorum. 
 
 Origin? From neighboring arterioles. 
 
 Nerves are distributed to which coat ? Middle. 
 
 From what system do they come? Cerebro-spinal and 
 sympathetic. 
 
 Name given to those from cerebro-spinal ? Vaso motor 
 dilators. 
 
 Effect on the artery if they are cut ? It contracts. 
 
 Effect if stimulated ? It dilates. 
 
 Effect if you cut the sympathetic ? It dilates. 
 
 Effect if you stimulate the sympathetic ? Contracts. 
 
 Does stimulation of the cerebro-spinal nerve to the artery 
 cause it to dilate ? It does not. 
 
 What does it counteract ? The sympathetic. 
 
 What causes the artery to dilate ? Pressure of the blood 
 in the artery. 
 
 How is the blood supply to a gland during its functional 
 activity ? Very much increased. 
 
 Relation of the blood supply to the heart's action? 
 Direct. 
 
 If the arteries were rigid tubes how would the heart have 
 to pulsate during digestion ? Very much faster. 
 
 What other force brings about the increased blood sup- 
 ply? Contractibility. 
 
ARTKRIKS. 47 
 
 How does the blood flow from the heart? In an inter- 
 mittent stream. 
 
 In the large arteries ? Intermittent. 
 
 Medium sized and small arteries? Remittent. 
 
 Capillaries ? Continuous. 
 
 What causes this change ? Elasticity of the arteries. 
 
 Which coat? Middle. 
 
 What trouble would there be if blood were supplied to 
 the tissues as it is sent out from the heart? Would have 
 rupture of the capillaries and bad nutrition. 
 
 Give example of elasticity of arteries? They are dis- 
 tended at each systole. 
 
 Function of the elasticity? Aid in circulation, modify 
 the force of the heart, and cause a continuous flow. 
 
 Does it assist in circulation? It does. 
 
 What conditions will cause more fluid to flow out of an 
 elastic than rigid tube ? The stream must be intermittent 
 and there must be valves. 
 
 Why? More fluid gets into the tube. 
 
 Proof that arteries are elastic ? Can distend them with 
 water. 
 
 Function of the contractibility of arteries? Regulate 
 the distribution of blood. 
 
 Proof of their contractibility ? Puncture them and they 
 will collapse. 
 
 What is " tonicity " of an artery ? The power of keeping 
 a certain amount of contraction. 
 
 When is it greatest ? In winter. 
 
 What is the function of the arterioles ? To regulate the 
 distribution of blood. 
 
 What is the locomotion of arteries ? The movements at 
 each systole of heart. 
 
 Where is it seen ? Where the arteries are tortuous and 
 superficial. 
 
48 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What is the pulse ? The force of the heart switched off 
 in the arteries. 
 
 Where do you feel it? At the radial artery. 
 
 Why select this one ? It is most superficial and rests on 
 a bone. ' 
 
 How make the pulse greatest ? Obstruct the blood be- 
 yond the point where you feel it. 
 
 When could the pulse not be felt ? When the arteries 
 are rigid from calcareous degeneration. 
 
 Name some different kinds of pulse ? Soft, hard, wiry, 
 thready, etc. 
 
 Time allotted to examine the pulse ? One-seventieth of 
 a minute. 
 
 Can the different characters be examined in this time ? 
 They can not. 
 
 How can you tell the characters ? By means of the sphyg- 
 mograph. 
 
 Describe the principle on which it is based? A lever 
 which registers the pulse on a revolving cylinder. 
 
 What does the first ascension of the lever represent? 
 The force of the heart. 
 
 Describe the descent ? Slow and irregular. 
 
 What does the second rise represent ? A second impulse. 
 
 Cause ? Elastic recoil of the arteries. 
 
 What condition favors a dicrotic pulse ? Low arterial 
 pressure. 
 
 What is arterial pressure ? The pressure of the blood in 
 the arteries. 
 
 Time of the year it is greatest ? Winter. 
 
 Why ? The arterioles are more contracted than in summer. 
 
 How is arterial pressure away from the heart? Lowered. 
 
 Effect of haemorrhage on arterial pressure ? Lowers it. 
 
 Effect of asphyxiated condition ? Increases it. 
 
 Why ? The blood is dammed back into the arteries. 
 
ARTERIES. 49 
 
 Effect of muscular contraction on arterial pressure? 
 Increases it. 
 
 Why ? By making pressure on the veins and compression 
 of chest also aids arterial flow. 
 
 Name the depressor nerve of circulation. Nerve of Cyon 
 and Ludwig. 
 
 Origin ? Pneumogastric and superior laryngeal nerves. 
 
 Anastomoses ? Sympathetic. 
 
 Distribution ? To the heart. 
 
 Effect if cut ? No effect. 
 
 Effect of stimulating the peripheral extremity ? No 
 effect. 
 
 Stimulating central end ? Lowers arterial pressure. 
 
 Effect if cut great splanchnic ? Lowers arterial pressure, 
 but not so much. 
 
 What is the rapidity of flow of blood in large arteries ? 
 Twenty inches per second. 
 
 What does it represent ? The force of the heart. 
 
 Condition after impulse ? Eight inches per second. 
 
 What does this represent? Elastic recoil of the arteries. 
 
 Condition after the second impulse? Five inches per 
 second. 
 
 Which diminish as you recede from the heart? Twenty 
 and eight, intermittent flow. 
 
 Which increase ? Five, continuous flow. 
 
50 COMPEXD OF HUMAN PHYSIOLOGY. 
 
 CHAPTER VIII. 
 
 CAPILLARIES. 
 
 Give the anatomical definition of capillaries ? The small- 
 est blood vessels. 
 
 Give the physiological definition? Those vessels that 
 bring the blood close enough to the tissues to give off its nu- 
 triment. 
 
 Give their physiological anatomy? Have but a single 
 coat, a homogeneous membrane. 
 
 Like what other coat? Like the endocardium. 
 
 Size of capillaries? One two - thousandth to one six- 
 thousandth inch. 
 
 Where find smallest? Nervous and muscular tissue, ret- 
 ina of eye and Peyer's patches. 
 
 Where find those of medium size ? Mucous membranes 
 and mucous la3 T er of skin. 
 
 Where largest? Bones and glands. 
 
 Where are they most abundant? Nervous and muscular 
 tissue. 
 
 Give their general characters ? They have no definite di- 
 rection, uniform in diameter, anastomose freely and have but 
 a single coat. 
 
 Describe the capillary circulation? Flows rapidly in the 
 middle and has a still layer on the side. 
 
 Cause of the still layer? Capillary attraction. 
 
 What part of capillary do you find the red corpuscle ? 
 In the middle. 
 
 Where the white? In the " still layer." 
 
 What are stomata? Holes in the walls of the capillaries. 
 
 What is the capacity of the capillaries? Five hundred 
 to eight hundred times that of arteries. 
 
 Cause of capillary circulation ? Vis-a-tergo. 
 
VEINS. 51 
 
 Rapidity of capillary circulation ? One-fortieth to one- 
 thirtieth inch per second. 
 
 Relation of rapidity to respiration ? Direct. 
 
 Effect of cold? Contracts the capillaries and lessens the 
 rapidity. 
 
 Effect of heat? Dilates the capillaries and increases the 
 rapidity. 
 
 Effect of an irritant ? Causes contraction at first. 
 
 Contraction is followed by what? Dilatation. 
 
 What is the first step of inflammation ? Dilatation of 
 the capillaries. 
 
 CHAPTER IX. 
 
 VEINS. 
 
 What is their only function ? To carry the blood back to 
 the heart. 
 
 How are they divided ? Superficial and deep. 
 
 What are superficial veins ? Those returning the blood 
 from the surface. 
 
 What are deep veins ? Those accompanying arteries. 
 
 Are all arteries accompanied by veins ? They are not. 
 
 Which is not? Ext. carotid. 
 
 How many have the arteries of the extremities ? Two. 
 
 Name those that have three ? Brachial and spermatic. 
 
 What is the capacity of veins ? Two and a half to four 
 times that of the arteries. 
 
 Where greatest? In brain. 
 
 Does the amount of blood in the arteries vary? No. 
 
 Does it in veins ? Yes. 
 
 Why do veins anastomose ? For blood to be sure and get 
 back to the heart. 
 
52 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Name the coats of veins. External, middle and internal. 
 
 Which are like those of the arteries ? Internal and ex- 
 ternal. 
 
 Describe the middle coat. A double layer of muscular 
 fibres. 
 
 Where have veins but one coat? In bones and the sin- 
 uses of the brain. 
 
 Which is thickest, artery or vein ? Artery. 
 
 Why will a vein collapse when cut? On account of tlleir 
 thin walls. 
 
 What vein will not? The hepatic vein. 
 
 Why not? It is held open by adjacent hepatic tissue. 
 
 Which is strongest, artery or vein? Vein. 
 
 Exception ? Splenic. 
 
 What is the outlet of the arteries ? Capillaries. 
 
 Of veins ? The heart. 
 
 Why should veins be stronger than arteries ? Their out- 
 let is smaller. 
 
 Veins are strongest in which extremity? Lower. 
 
 Proof of elasticity of veins ? Distend them with water. 
 
 Proof of their contractility? Cut them and they con- 
 tract. 
 
 Where do you find valves in veins ? Everywhere, except 
 in the cavities. 
 
 Where is the valve situated ? Just beyond where a branch 
 empties into the vein. 
 
 Describe the valve. Fold of the internal coat. 
 
 Where is the vein weakest? Between the valves. 
 
 Are there any valves in the spermatic vein ? Yes. 
 
 Into what does the left spermatic vein empty ? Left renal. 
 
 Into what does the left renal empty ? Inferior vena cava. 
 
 At what angles do they both empty ? Right angles. 
 
 What is varicocele ? Dilatation of the spermatic veins. 
 
 On which side does it occur most ? Eeft. 
 
veins. 53 
 
 Why? The blood has two right angles to overcome and 
 pressure of the sigmoid flexure on the left spermatic vein 
 favors it. 
 
 What are piles ? Dilatation of the hemorrhoidal veins. 
 
 Causes that predispose to them ? Looseness of the mu- 
 cous membrane of the rectum and absence of valves in the 
 veins. 
 
 What other outlet besides the liver have the hemorrhoidal 
 veins ? Internal iliac vein. ' 
 
 Are the valves in the external jugular vein perfect ? No. 
 
 What does pulsation in it indicate ? Tricuspid regurgi- 
 tation. 
 
 With what does the internal jugular vein unite ? Sub- 
 clavian vein. 
 
 What do they form ? Vena innominata. 
 
 Why should there be perfect valves in the internal jugu- 
 lar vein ? To protect the brain. 
 
 Why not necessary in the external ? Reflex of blood 
 does no harm. 
 
 The internal returns blood from what kind of tissue ? 
 Nervous tissue. 
 
 The external from what kind? Muscular tissue. 
 
 How is the flow of blood in arteries ? Intermittent and 
 remittent. 
 
 How is it in capillaries ? Continuous. 
 
 How flow in veins ? Continuous. 
 
 What is the course of the veins ? Almost direct. 
 
 How are they arranged so that their onward flow shall 
 not be impeded ? They anastomose. 
 
 Under what circumstances would the flow be intermit- 
 tent in veins ? During the functional activity of a gland. 
 
 How is venous pressure compared to arterial ? Inversely, 
 in proportion. 
 
 Rapidity of flow in veins ? Half as fast as arteries. 
 
54 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What is the main cause of venous circulation? Vis-a- 
 tergo. 
 
 Name the causes that assist. Intermittent muscular eon- 
 traction, gravity, inspiration and contraction of the veins. 
 
 When will muscular contraction aid it ? When it is in- 
 termittent and the valves are perfect. 
 
 What act of respiration increases it ? Inspiration. 
 
 How ? It produces a suction force. 
 
 To what distance does this force act ? To the liver below 
 and the jugular veins above. 
 
 Why does it extend to the liver ? Because the hepatic 
 vein stands open. 
 
 What will a vein do if suction force is applied to it out- 
 side of the body ? It will collapse. 
 
 Why not collapse when inside of body ? The blood 
 holds it open. 
 
 Give illustration of gravity assisting venous circulation ? 
 Hold hand up with veins distended and they empty. 
 
 Which coat of veins is contractile ? The middle. 
 
 What is the function of valves ? To prevent backward 
 flow. 
 
 What conditions impede venous circulation ? Continu- 
 ous muscular contraction, gravity, expiration, contraction of 
 the right side of heart. 
 
 What act of respiration is the thoracic cavity smallest ? 
 Expiration. 
 
 What kind of muscular contraction will retard ? Con- 
 tinuous. 
 
 When is the blood not flowing into heart? During 
 auricular systole. 
 
 What is the course of the blood then ? Into the ven- 
 tricles. 
 
 What kind of a box is the cranial cavity ? An air-tight 
 box. 
 
veins. 55 
 
 Is it subject to atmospheric pressure ? It is not. 
 
 Does the quantity of fluid in the cranial cavity vary ? 
 No. 
 
 Does the quantity of blood vary? Yes. 
 
 What fluid equalizes the blood pressure ? Cephalo Ra- 
 chidian fluid. 
 
 Where do you find it ? In the the sub-arachnoid space 
 and central canal. 
 
 Where does the central canal communicate with the 
 brain ? At the floor of the fourth ventricle. 
 
 When does this fluid rise up ? During anaemia of the 
 brain. 
 
 When does it recede ? During hyperemia of the brain. 
 
 During what act of respiration do the fontanelles bulge ? 
 Expiration. 
 
 Why ? Expiration aids arterial circulation and retards 
 venous. 
 
 When recede ? Inspiration. 
 
 Why ? Inspiration aids venous and retards arterial flow. 
 
 Peculiarity of the vessels of the brain? They are sur- 
 rounded by large lymphatics. 
 
 Give the physiological anatomy of the corpus caverno- 
 sum ? It is surrounded by a delicate fibrous membrane which 
 sends bands into the interior which divides it into cells. 
 
 Describe the arteries of the penis ? Large and tortuous, 
 have onl}- one coat, and give off large arborescent branches. 
 
 What is the first thing in the process of erection ? Hy- 
 per semia. 
 
 Describe it? The vessels relax and the blood rushes in. 
 
 Is it a congestion ? No. 
 
 Describe " derivative circulation? " Where arteries com- 
 municate with the veins without the intervention of capilla- 
 ries. 
 
 Where found ? Elbow, knee, cheeks. 
 
56 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Peculiarities of pulmonary circulation? Artery is thin- 
 ner and more distensible, capillaries large and allow the pas- 
 sage of any kind of blood, and the right side of the heart is 
 weaker and valves are imperfect. 
 
 What is a circuit? Where blood goes from the heart to 
 the tissues and back. 
 
 How many are there ? Two. 
 
 Name them ? Greater or systemic, and lesser or pulmo- 
 nary. 
 
 Describe each ? Greater begins at the left ventricle and 
 ends at right auricle, the lesser begins at right ventricle and 
 ends at left auricle. 
 
 In what time does the blood make both ? Twenty-three 
 seconds. 
 
 On what experiment is it based ? Inject one jugular with 
 ferrocyanide of potassium and watch for it in the one on the 
 other side. 
 
 How much blood is sent out at each pulsation of the 
 heart? Five ounces. 
 
 How many would it take for all the blood to pass 
 through? Forty-five pulsations. 
 
 How long does it take for all to pass through ? Twenty- 
 three seconds. 
 
 What kind of increase of heart's action would increase 
 the rapidity of the circulation? Pli3 T siological. 
 
 What kind of circulation do you have in fevers ? Weak. 
 
 After death, where is the blood ? In the veins. 
 
 Why? There is a post mortem contraction of the arteries. 
 
RESPIRATION. 57 
 
 CHAPTER X. 
 
 RESPIRATION. 
 
 Name the kinds of blood? Arterial, venous and capillary. 
 
 Which have been examined? Arterial and venous. 
 
 Give the characters of arterial ? Bright red and will sup- 
 port nutrition. 
 
 Characters of venous blood? Blue black and will not 
 support nutrition. 
 
 Character of capillary blood ? Has not been examined. 
 
 From what do the principles come that are given off in 
 the lungs? The blood. 
 
 What becomes of the loss in air in passing through the 
 lungs? Goes to the blood. 
 
 What is the relation of oxygen to the circulation? It is 
 direct. 
 
 Define respiration ? The process by which the tissues re- 
 ceive oxygen and give off carbonic acid. 
 
 How does the oxygen reach the tissues ? Through the 
 blood. 
 
 Could tissue take on oxygen without blood? Yes. 
 
 Example? Detached portions of tissue take on oxygen. 
 
 What was the old idea as to where respiration took 
 place ? In the lungs. 
 
 Does the introduction of air into the lungs constitute res- 
 piration? No. 
 
 Example ? Drain the system of blood and introduce air 
 into the lungs, and will have symptoms of asphyxia. 
 
 What part do the lungs play ? Receptacle for the air and 
 blood. 
 
 In the lowest form of life how is respiration carried on ? 
 By the general surface. 
 
 How do fish receive oxygen? Through their gills. 
 
58 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What is the respiratory apparatus in higher animals ? 
 Lungs. 
 
 What conditions are necessary for respiration where 
 there are lungs ? Blood and air separated by a membrane 
 through which the gases can pass. 
 
 On what is the rapidity of changes dependent? The ra- 
 pidity of the circulation and activity of nutrition. 
 
 Name the openings in the pharynx ? Mouth, posterior 
 nares, Eustachian tube, larynx and oesophagus. 
 
 What kind of tube is the oesophagus ? Flaccid. 
 
 What kind is the trachea? Risrid. 
 
 Why do they differ? Because Jthey perform different func- 
 tions. 
 
 What is the shape of the larynx ? Hour-glass shape. 
 
 Describe the vocal cords ? Fibrous bands that extend from 
 the thyroid to the arytenoid cartilage. 
 
 On which is the mucous membrane thickest? On the 
 superior. 
 
 What is the glottis ? Opening from pharynx to larynx. 
 
 What is the epiglottis? Leaf-like lamella covering the 
 glottis. 
 
 Is it essential ? No. 
 
 Proof? Remove it and can do without it. 
 
 What is the rima glottis ? The chink between the vocal 
 cords. 
 
 When is it open ? At inspiration and expiration. 
 
 What protects it during deglutition ? The superior laryn- 
 geal nerve. 
 
 What is it a branch of ? Pneumogastric. 
 
 What nerve animates the intrinsic muscles of the larynx ? 
 The inferior laryngeal. 
 
 What is it a branch of? Pneumogastric. 
 
 Effect if it is cut in young ? Cartilages collapse and have 
 suffocation. 
 
RESPIRATION. 59 
 
 What if cut in the adult? Borders on suffocation. 
 
 What is the nerve of voice ? Recurrent laryngeal. 
 
 The power comes from what nerve? Spinal accessory 
 nerve. 
 
 What root ? Upper. 
 
 From what points does the trachea extend ? From fifth 
 cervical to third dorsal vertebra. 
 
 How many coats has it? Two. 
 
 Where are the rings ? Between the two coats. 
 
 How many rings in the trachea ? Fifteen to eighteen. 
 
 How far around do they extend? Two-thirds the way 
 around. 
 
 What is at the posterior third ? Trachealis muscle. 
 
 How many layers has the muscular coat of the oesopha- 
 gus ? Two. 
 
 Describe the external layer? It is in three fasiculae, above 
 which all blend in one below. 
 
 Describe the internal layer ? It is thinner and circular in 
 direction. 
 
 What kind of fibres in the upper part ? Striated. 
 
 In the lower part ? Nonstriated. 
 
 What kind of epithelium lines the oesophagus? Squa- 
 mous. 
 
 What kind of glands has the mucous membrane ? Small 
 racemose. 
 
 What is the condition of the lower part of the oesophagus 
 after the bolus has passed ? It is constricted. 
 
 How many bronchial tubes are there ? Two. 
 
 How do they divide ? Dicotomously. 
 
 How terminate ? In intercellular air passages. 
 
 Where? One-eighth of an inch from surface of lung. 
 
 Shape of rings in small tubes ? Irregular. 
 
 How do the air passages terminate ? In air cells. 
 
 What is the shape of an air cell ? Oblong. 
 
60 COMPEXD OF HUMAN PHYSIOLOGY. 
 
 Where largest ? Near the surface. 
 
 Give the parenchyma of the lungs? Air cells, inter- 
 cellular air passages, connective tissue, blood vessels and 
 lymphatics are held together by the subserous areolar 
 tissue. 
 
 What is the external covering ? Pleura. 
 
 What kind of membrane is it ? Serous. 
 
 What do you find beneath it ? Subserous areolar tissue. 
 
 Describe the elastic tissue? Small elastic fibres which 
 have no definite direction but connect the air cells. 
 
 What give the lungs elasticity? Serous and subserous 
 tissue and the elastic fibres. 
 
 Where do you find the richest capillary flexus ? In the 
 lungs around the air cells. 
 
 How arranged? To surround the air cells. 
 
 What kind of blood nourishes the lungs ? Arterial. 
 
 What do the bronchial arteries supply ? Bronchial tubes 
 and lung substance. 
 
 Which lung has two arteries ? Left. 
 
 What is bronchitis ? Inflammation of mucous membrane 
 of the bronchial tubes. 
 
 What is pneumonia ? Inflammation of the parenchyma 
 of lung. 
 
 Will bronchitis cause pneumonia ? No. 
 
 Why not ? They have different blood supply. 
 
 What acts make up respiration? Inspiration and expira- 
 tion. 
 
 Which is active ? Inspiration. 
 
 Why? It is produced by muscular contraction. 
 
 Which is passive ? Expiration. 
 
 Peculiarities of the first rib? Shorter, more horizontal, 
 and the sternal extremity is the most firmly fixed. 
 
 Direction of the other ribs? Oblique. 
 
 Which rib is longest? Eighth. 
 
 
RESPIRATION. 6 1 
 
 When the thorax is raised, in which direction is the tho- 
 racic cavity enlarged? In every direction. 
 
 What ribs approximate ? Upper four. 
 
 Which separate ? Lower eight. 
 
 Name the muscles of ordinary inspiration? Diaphragm, 
 three scalenii, external intercostal, sternal portion of internal 
 intercostals and levatores costarum. 
 
 Which is the most important one? Diaphragm. 
 
 Shape? Dome shaped. 
 
 How is it divided? Thoracic and lumbar portion. 
 
 Where is it muscular ? At the edge. 
 
 How is it in the center ? Tendinous. 
 
 Give the origin of the thoracic portion ? Ensiform carti- 
 lage and six lower ribs. 
 
 Where is it inserted ? Into the central tendon. 
 
 How is the lumbar part divided ? Into two crura. 
 
 Which crus is largest? Right one. 
 
 Name the pillars in each one, also, their origin? Internal, 
 from third lumbar vertebra ; middle, from second lumbar ver- 
 tebra; external, from first, second and third lumbar vertebra ; 
 intervertebral substance of the first, second, third and fourth, 
 ligamentum arcuatus internum and externum and last rib. 
 
 Arrangement of the internal pillar? Figure of eight 
 opening around the aortic and oesophageal openings. 
 
 Give the attachment of ligamentum areuatum externum ? 
 From the apex of the transverse process of third lumbar ver- 
 tebra to the last rib. 
 
 Arches over what muscle ? Quadratus lumborum muscle. 
 
 Describe ligamentum areuatum internum. Extends from 
 apex to transverse process. 
 
 It arches over what muscle ? Psoas magnus. 
 
 Describe the central tendon ? It is the shape of a trefoil 
 leaf, with the middle leaflet directed forward. 
 
 Which leaflet is largest ? Anterior. 
 
62 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Name the openings in the diaphragm ? Aortic, oesopha- 
 geal and opening for the inferior vena cava. 
 
 Give boundaries of the aortic portion? Bone behind, 
 internal pillars laterally and a tendinous arch in front. 
 
 What passes through it? Aorta and thoracic duct. 
 
 Why do they pass through there ? So that no pressure is 
 made on them by the contracting diaphragm. 
 
 Where is the oesophageal opening ? In the muscular por- 
 tion. 
 
 Why ? To prevent regurgitation of food during inspira- 
 tion. 
 
 Where is the opening for inferior vena cava ? Tendi- 
 nous portion between the right and middle leaflets. 
 
 Why? So no pressure is made on it. 
 
 What nerve supplies the diaphragm ? Phrenic. 
 
 Give its origin ? Third, fourth and fifth cervical nerves. 
 
 In inflammation of the diaphragm where is the pain? 
 Shoulder, acromion process and clavicle. 
 
 Why? Nerves from the anterior cervical plexus supply 
 both these parts. 
 
 What elevates and fixes the first rib ? The scalenae 
 muscles. 
 
 Direction of the fibres of the external intercostal muscles? 
 Downward and forward. 
 
 What end of a rib is most firmly fixed ? Vertebral end. 
 
 What is the origin of a muscle ? A fixed point. 
 
 What is the origin of the external intercostals ? Verte- 
 bral extremity of the ribs. 
 
 Why do they take their origin there ? To take their ori- 
 gin from above. 
 
 How are the ribs pulled when they contract? Upward. 
 
 Name the ordinary auxiliary muscles of inspiration? 
 Serratus posticus superior and sterno cleido mastoid. 
 
 Describe them ? See anatomy. 
 
RESPIRATION. 63 
 
 Give the extraordinary auxiliaries ? Levator angulae 
 scapulae, trapezius, pectoralis major and miuor, and serratus 
 magnus. 
 
 When used ? When respiration is greatly interfered with. 
 
 In what diseases is it used? Capillary bronchitis and 
 asthma. 
 
 Describe these muscles ? See anatomy. 
 
 What is expiration ? Expulsion of air from the lungs. 
 
 What kind of an act ? Passive. 
 
 What two forces produce it ? Elasticity and muscular 
 contraction. 
 
 Source of the elasticity ? Lungs and thorax. 
 
 Prove that the lungs are elastic ? Can distend them by 
 blowing them up. 
 
 Why do the lungs go down in inspiration ? There is a 
 suction force produced when the diaphragm contracts. 
 
 Why do the lungs not fully collapse after death ? The 
 w r alls of the thorax prevent atmospheric pressure on them. 
 
 When are the thoracic walls most elastic ? Earl y life. 
 
 Why ? The ribs contain more animal matter and are con- 
 sequently more elastic. 
 
 Why are fractures so frequent in old age ? The bones 
 are brittle in old age. 
 
 What kind of fractures do you find in young? Green 
 stick fractures. 
 
 Why ? The bones are very elastic. 
 
 Name the muscles of ordinary expiration ? Osseous por- 
 tion of the internal intercostals, infracostales, and triangu- 
 laris sterni. 
 
 Describe them ? See anatomy. 
 
 Ordinary auxiliaries ? The abdominal muscles. 
 
 Describe them? See anatomy. 
 
 Name the types of respiration ? Abdominal and superior 
 and inferior intercostal types. 
 
64 COMPEXD OF HUMAN PHYSIOLOGY. 
 
 When use the abdominal type? In children. 
 
 What muscle performs it ? The diaphragm. 
 
 What is the inferior intercostal type ? Where the lower 
 part of the thorax is most prominent in the movements. 
 
 When used? By the adult male. 
 
 What is the superior intercostal type ? Where the upper 
 part of the thorax is most prominent in the movements. 
 
 By whom is it used ? By the adult female. 
 
 Why ? So that during pregnancy the gravid uterus will 
 not interfere with respiration. 
 
 What is the frequency of respiration ? Average twenty 
 per minute. 
 
 What is the relation of respiration to the heart's action? 
 In the proportion of one respiration to every four beats of the 
 heart. 
 
 Does this hold good in disease ? Yes. 
 
 Exception? Pulmonary troubles. 
 
 Which breathes most rapid, male or female ? Male. 
 
 Do the acts of respiration follow each other immediately? 
 No. 
 
 Between which is there an interval ? Expiration and in- 
 spiration. 
 
 Describe the inspiratory sound over the bronchial tube ? 
 Tubular in character, attains its maximum intensity quickly 
 and ends abruptly. 
 
 Describe it over lungs substance ? Vesicular in character, 
 less intense, increases in intensity from beginning to the ter- 
 mination, and ends abruptly. 
 
 What causes the sound ? The expansion of the air cells 
 and the vibration of the air. 
 
 Describe the expiratory sound ? Shorter, lower in pitch, 
 soon attains its maximum intensity, and dies gradually. 
 
 Which act is the longest ? Expiration. 
 
 Which sound is longest? Inspiratory sound. 
 
RESPIRATION. 65 
 
 Peculiarity of every fourth respiration ? It is deeper than 
 the rest. 
 
 At what period of life are the sounds most intense ? 
 Children. 
 
 What is it called ? Puerile breathing. 
 
 Where do you find it in normal chest of male ? Apex of 
 right lung. 
 
 Why ? The right bronchus is larger and enters the lung 
 higher up. 
 
 Where do you hear it in normal chest of female ? Apex 
 of both lungs. 
 
 Why ? Because female breathes mostly with the upper 
 part of the lung. 
 
 What is the cause of snoring ? Flapping of the uvula 
 between the two currents of air from mouth and nose. 
 
 Cause of coughing and sneezing ? Irritation of nasal or 
 respirator}- passages. 
 
 Give the mechanism ? A deep inspiration followed by a 
 convulsive expiration. 
 
 Give the mechanism of yawning and sighing? Deep 
 inspiration followed by a rapid and audible expiration. 
 
 What is the cause of each? An effort to get more oxygen. 
 
 Give the mechanism of laughing and crying ? Convulsive 
 movements of the diaphragm, accompanied by contraction of 
 the muscles of the face. 
 
 During what act of respiration do they occur ? Expira- 
 tion. 
 
 What is hiccough? A peculiar modification of inspiration. 
 
 Cause of hiccough ? Dry food or effervescent drink. 
 
 Give the mechanism ? Spasmatic contraction of the dia- 
 phragm, accompanied by spasmatic constriction of the glottis. 
 
 What is residual air? That that can not be expelled from 
 lungs. 
 
 Amount ? One hundred cubic inches. 
 5 
 
66 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Why is it necessary for air to remain in lungs ? To 
 make respiration continuous. 
 
 What is reserve air ? That that can be expelled from 
 lungs, but is not expelled at an ordinary expiration. 
 
 Amount? One hundred cubic inches. 
 
 Function ? To be used in prolonged vocal efforts. 
 
 What is the tidal air? That used in ordinary respiration. 
 
 Amount? Twenty cubic inches. 
 
 What is complemental air? All that can be taken in over 
 and above a normal inspiration. 
 
 Amount? One hundred and ten cubic inches. 
 
 What is the vital capacity? All that can be changed by 
 a prolonged inspiration and forcible expiration. 
 
 It includes what airs? All except the residual. 
 
 Amount? Two hundred and thirty cubic inches. 
 
 Does air lose or gain in passing through lungs ? Loses. 
 
 How much? One-seventieth to one-fiftieth. 
 
 Which element ? Oxygen. 
 
 What causes tidal air to go down into the air cells ? 
 The diffusibility of gases. 
 
 Give the law of diffusibility of gases ? They diffuse with 
 inverse ratio to the square root of their densities. 
 
 What is the atomic weight of hydrogen ? One. 
 
 Of oxygen? Sixteen. 
 
 What is the square root of each ? Of one it is one ; of six- 
 teen, it is four. 
 
 Which diffuses fastest? Hydrogen. 
 
 Is respiration continuous ? Yes. 
 
 What was the old idea as to the function of respiration ? 
 To cool the blood. 
 
 Why? Because they found expired air warmer than in- 
 spired air. 
 
 What is the air? The atmosphere in which we live. 
 
 Is it a mixture or chemical compound ? Mixture. 
 
RESPIRATION. 67 
 
 What is its composition ? Nitrogen four parts and oxy- 
 gen one part. 
 
 Effect of breathing dense air? Respiration is disturbed. 
 
 Effect of breathing light air ? It is seriously interfered 
 with. 
 
 What trouble would there be if the oxygen of the air 
 were diminished from three to five per cent. ? Death. 
 
 Effect of breathing pure oxygen? No effect. 
 
 What other gas will support respiration for a short time ? 
 Nitrous oxide gas. 
 
 Why was this gas called "laughing gas?" It produces 
 delirium and exhilaration. 
 
 How will it cause death ? It combines with oxygen in 
 the corpuscle. 
 
 What gases produce death negatively? Hydrogen, ni- 
 trogen and carbonic acid gas. 
 
 Which kill positively? Arseniureted hydrogen, sulphur- 
 etted hydrogen and carbon monoxide gas. 
 
 How prove the loss of air in passing through lungs? 
 Measure the oxygen inhaled and carbonic acid gas exhaled. 
 
 How many parts of oxygen in every one hundred parts 
 of inspired air ? Twenty-one parts. 
 
 How many uncombined in expired air ? Sixteen parts. 
 
 Combined in expired air ? Four parts. 
 
 What does it form ? Carbonic acid gas. 
 
 How many parts lost in respiration ? One part. 
 
 Amount of tidal air? Twenty cubic inches. 
 
 Number of respirations in a day? Twenty-six thousand. 
 
 Amount of air changed in a day? Three hundred cubic 
 feet. 
 
 Amount of oxygen consumed in a day? Fifteen cubic 
 feet. 
 
 What will increase the consumption of oxygen ? Exer- 
 cise, digestion and young age. 
 
68 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Diminish it ? Fasting, sleep and old age. 
 
 What effect has mixing of hydrogen with it ? Increases 
 the consumption. 
 
 In what does the air gain in passing through the lungs ? 
 Carbonic acid gas, moisture, ammonia and organic matter. 
 
 How much carbonic acid gas in inspired air? Only a 
 trace. 
 
 How much in expired air? Four per cent. 
 
 Name the elements of carbonic acid gas. Carbon and 
 ox}' gen. 
 
 What is their origin? From the tissues. 
 
 How was the amount determined ? Measuring it. 
 
 How much is exhaled in a day ? Fourteen cubic feet. 
 
 How much carbon ? Seven ounces. 
 
 What part of expiration is most expired? The last 
 part. 
 
 Effect of rapid breathing on the amount of carbonic acid 
 expired ? It increases it. 
 
 State those things that will increase the exhalation of 
 carbonic acid gas ? Young age, males, digestion and exer- 
 cise. 
 
 Those that will diminish it? Old age, females, fasting 
 and sleeping. 
 
 Why less during the menstrual period ? It is eliminated 
 vicariously. 
 
 Give the relation between the inhalation of oxygen and 
 exhalation of carbonic acid ? They are in direct relation. 
 
 What becomes of the one part of oxygen left in the or- 
 ganism ? It is thought to form water. 
 
 What favors the formation of water ? Exercise. 
 
 What is the source of carbonic acid in expired air? 
 From the tissues. 
 
 Name the forms in which it is found in the blood ? Free 
 and in the form of carbonates and bicarbonates. 
 
RESPIRATION. 69 
 
 How are these displaced ? By the pneumic acid in the 
 lungs. 
 
 How much water is exhaled in a day ? One and one-fifth 
 pound. 
 
 What is the origin of water ? From the oxidation of hy- 
 drogen. 
 
 How prove ammonia is exhaled ? Can smell it. 
 
 Proof of organic matter? Breathe into a sponge and 
 leave it set, the organic matter becomes decomposed. 
 
 Does the air gain or lose in nitrogen ? Gains a little. 
 
 What is hsematosis ? The changes that the blood under- 
 goes in passing through the lungs. 
 
 What are the changes? Change of color, composition 
 and properties. 
 
 What is the capital phenomena of respiration as regards 
 the air in the lungs ? The loss in oxygen and gain in car- 
 bonic acid. 
 
 The accessory phenomena ? The gain in water, ammonia, 
 nitrogen and organic matter. 
 
 What is the general difference between arterial and ve- 
 nous blood ? In the amount of oxygen they contain. Ar- 
 terial blood is uniform in composition and venous is not. 
 
 With what part of the blood is the oxygen in combina- 
 tion? The coloring matter in the red corpuscle. 
 
 What is the difference between the absorption of oxygen 
 by water and the corpuscle ? Corpuscle absorbs fifty times 
 as much as water. 
 
 How is the absorption of oxygen by plasma ? Twice as 
 great as water. 
 
 How can you increase the carbonic acid absorbing power 
 of the plasma ? By adding phosphate of soda to it. 
 
 What was the old method of separating gases from the 
 blood? By air pressure. 
 
 Fallacy of this method ? The blood reabsorbed the gases. 
 
70 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Proof of post-mortem absorption of oxygen ? Venous 
 clot becomes red. 
 
 What is formed when oxygen is consumed? Carbonic 
 acid gas. 
 
 What is the present method of separating gases from the 
 blood ? Add carbon monoxide gas to absorb the oxygen and 
 then air pressure. 
 
 What is the difference between the amount of oxygen in 
 venous and arterial blood ? About twice as much in arterial. 
 
 Difference in the amount of carbonic acid ? Venous has 
 about four per cent. more. 
 
 Does the blood gain or lose in nitrogen in its passage 
 through the lungs ? Loses a little. 
 
 In what condition is oxygen in the blood? Unstaple 
 combination with the haemoglobin. 
 
 Why? So it can be readily given up to the tissues. 
 
 Condition of carbonic acid ? In solution in the plasma. 
 
 Why ? It is soluble in the plasma. 
 
 Give the mechanism of the interchange of gases in the 
 lungs ? Oxygen of the air passes down through the mem- 
 brane into the blood and the carbonic acid is pushed out. 
 
 What is the relation of respiration to nutrition? Direct. 
 
 When respiration is disturbed, to what organ is it re- 
 ferred ? To the lungs. 
 
 Does respiration take place there ? Xo. 
 
 Does respiratory sense reside there ? No. 
 
 Proof that it does not? Drain the system of blood and 
 introduce air in the lungs, and will still have efforts at res- 
 piration. 
 
 Does it reside in tissue ? No. 
 
 Where is it located ? In the respiratory center. 
 
 Proof? Stimulate it and will cause efforts at respiration. 
 
 Cause of respiration? Want of oxygen in the respiratory 
 center. 
 
RESPIRATION. 71 
 
 Is it direct or reflex ? Direct. 
 
 What do you mean by direct? Originating in the 
 center. 
 
 Why do the bowels act after death? Want of oxygen in 
 the centers acts as an irritant. 
 
 How does respiratory sense differ from the sense of suf- 
 focation? Only in intensity. 
 
 Does the foetus breathe ? No. 
 
 Why not? Its blood is aerated in the placenta. 
 
 When would it breathe ? When it does not get enough 
 oxygen. 
 
 What are the functions of the placenta? It takes the 
 place of the lungs and stomach. 
 
 What part of respiration takes place by the skin ? One- 
 fiftieth to one-fortieth. 
 
 Is it very important ? No. 
 
 What is asphyxia ? Want of oxygen by the tissues. 
 
 What are the symptoms? Full, strong pulse. 
 
 Why does pulse become full ? To overcome the obstruc- 
 tion in the systemic capillaries. 
 
 At what period of life do we resist asphyxia longest? 
 Childhood. 
 
 Why ? Their demand for ox}'gen is less. 
 
 What is the most important question connected with 
 asphyxia? The effect of carbonic acid on the system. 
 
 What was the old idea ? That it killed positively. 
 
 Present idea ? It kills negatively. 
 
 Reason for thinking so ? Increase the oxygen iu propor- 
 tion to the carbonic acid and it will not kill. 
 
 On entering a crowded room, what sensation is experi- 
 enced? Sense of oppression. 
 
 What becomes of it ? It is lost. 
 
 Why ? You become accustomed to it. 
 
 Trouble of rebreathing air ? Danger of asphyxia. 
 
72 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What condition resists asphyxia longest? Debilitated 
 condition. 
 
 Give illustration? Put a sparrow under a bell jar ; in a 
 short while put another under, the latter will die first. 
 
 Why will an invalid live longer than a healthy subject, 
 both breathing poisoned air ? The demand for oxygen is 
 not so great in the invalid. 
 
 CHAPTER XI. 
 
 ALIMENTATION. 
 
 What becomes of all tissue? Ans. It wears out. 
 
 When organic tissue wears out, what does it produce ? 
 Effete matter. 
 
 What is the destination of inorganic matter ? It is elim- 
 inated. 
 
 Trouble if the excrementitious products are not thrown 
 off? Would have poisoning. 
 
 Can this wear be arrested ? No. 
 
 What fluid furnishes elements for the formation of new 
 material ? Blood. 
 
 What does the blood contain ? All the elements neces- 
 sary for nutrition. 
 
 How do you keep it from becoming impoverished ? By 
 the introduction of food. 
 
 What is the want on the part of the system called ? 
 Hunger. 
 
 What is the first sensation of hunger? Appetite. 
 
 What kind of sensation is it ? Not unpleasant. 
 
 What does it become if not appeased ? Hunger. 
 
 Effect of introducing food? It is lost. 
 
ALIMENTATION. 73 
 
 What do we have ? A sense of satisfaction. 
 
 What if too much food is introduced? A sense of fullness. 
 
 How often do we get hungry ? Three or four times a da)'. 
 
 On what does it depend ? Habit. 
 
 What are the variations of hunger at different periods of 
 life ? Old and young get hungry most often. 
 
 Why ? Is more tissue waste. 
 
 What time of the year get hungry oftenest ? In winter. 
 
 Why? The food is more palatable and nutrition more 
 active. 
 
 What effect has physical exercise ? Increases it. 
 
 Why ? It causes more tissue waste. 
 
 What condition is most favorable to appetite ? To take a 
 moderate amount of exercise. 
 
 What conditions diminish it ? Fatigue and the adminis- 
 tration of drugs like opium or alcohol. 
 
 What symptoms will you have if hunger is not satisfied ? 
 Pain in the epigastric region and frontal headache. 
 
 Effect of hunger over moral and intellectual faculties ? 
 It blunts them. 
 
 To what organ is hunger referred? Stomach. 
 
 Where located ? In the tissues. 
 
 Proof? Introduce food into the stomach and let it run 
 out at a fistula, will still have hunger. 
 
 Does the brain take cognizance of hunger? Yes. 
 
 Through what nerves ? Sympathetic. 
 
 Prove that it does not through the pneumogastric. Cut 
 the pneumogastric and will still have hunger. 
 
 How long can one live without food ? Forty da}'S. 
 
 What is thirst ? Call on the part of the tissues for water. 
 
 What are the symptoms ? Dryness of the throat and 
 fauces. 
 
 What element is most necessary to life ? Oxygen. 
 
 How long will one live without it ? Three to five minutes. 
 
74 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Next most important to oxygen ? Water. 
 
 How long can one live without water ? Three to six 
 days. 
 
 If thirst is not satisfied what symptoms would you 
 have? Visceral inflammation. 
 
 Where is thirst located ? In the tissue. 
 
 Proof? Thirst can be appeased without passing the water 
 through the mouth. 
 
 What is aliment ? Substances appropriated by the organ- 
 ism, or aiding in nutrition. 
 
 How divided? Direct and accessory. 
 
 Define direct ? That is directly appropriated by the tissue. 
 
 Define accessory? That assists assimilation and retards 
 disassimilation. 
 
 How is food divided ? Organic and inorganic. 
 
 Name the division of the organic ? Into nitrogenized and 
 non-nitrogenized . 
 
 Name the nitrogenized food?* Albumin, musculin, ca- 
 sein and fibrin. 
 
 Which is the most important one ? Musculin or my- 
 osin. 
 
 What is musculin ? Organic nitrogenized principle of 
 muscle. 
 
 It is united with what ? Inorganic matter. 
 
 How is it separated? By incineration. 
 
 Will flesh support life ? Yes. 
 
 Why ? It contains a variety of principles. 
 
 Will musculin support life ? No.- 
 
 Why not? Has no variety of principles. 
 
 Where is flesh digested ? Stomach. 
 
 Where myosin digested ? In small intestine. 
 
 How is albumin usually taken ? In the form of eggs. 
 
 Will albumin support life ? Xo. 
 
 Will eggs ? Yes. 
 
ALIMENTATION. 75 
 
 Why ? They contain a variety of principles. 
 
 Where is albumin digested? Stomach. 
 
 What form of it is easiest digested ? In whipped eggs. 
 
 How do we take casein in early life ? In milk. 
 
 In adult life ? Cheese. 
 
 Where is cheese digested ? In the stomach. 
 
 What is the composition of this class of food ? Carbon, 
 hydrogen, oxygen, nitrogen, and a little sulphur. 
 
 Other name for this class ? Albuminoids or protoids. 
 
 What is the origin of nitrogen in vegetables ? From the 
 saline matters. 
 
 What is the action of heat and moisture on the nitrogen- 
 ized principles ? Makes them undergo putrefaction. 
 
 Action of digestion on them ? Changes them to pep- 
 tones. 
 
 Action of acid on them ? Changes them to peptones. 
 
 What is gluten? Xitrogenized proximate principle oi 
 cereals. 
 
 How is it obtained ? Powder them and knead under a 
 stream of water. 
 
 Color of gluten ? Gray. 
 
 Why will it support life? It has a variety of principles. 
 
 What are they? Glutin, albumin, and fibrin. 
 
 Bread made from gluten is used in what trouble ? Gly- 
 cosuria. 
 
 Why ? It contains no sugar-producing principle. 
 
 Name the non-nitrogenized class of food ? Sugar, starch, 
 and fats. 
 
 How do they differ from the nitrogenized ? The}- have 
 no nitrogen. 
 
 Which class is essential to life ? The nitrogenized. 
 
 What is the supposed function of the non-nitrogenized ? 
 To produce heat. 
 
 Why think so ? Because the}* are used most in winter. 
 
76 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Name the different kinds of sugar? Cane, milk, liver, 
 honey, grape sugar. 
 
 What is their composition? Carbon, hydrogen and oxy- 
 gen. 
 
 Properties of sugar? Sweet taste, soluble in water, burns 
 with a caramel odor and leaves a carbonaceous mass. 
 
 Which is the sweetest sugar ? Cane sugar. 
 
 What organ first produces it? Placenta. 
 
 In what blood do you find it ? Blood from the liver to 
 the lungs. 
 
 What is its destination? It is destroyed in the lungs. 
 
 Is it ever deposited ? No. 
 
 When would it be eliminated ? When a large amount is 
 taken in. 
 
 Reasons for thinking sugar produces fat? They both 
 contain the same elements, and people in sugar-growing re- 
 gions grow fat. 
 
 Origin of starch? Mostly from vegetables. 
 
 Form usually found in? In the form of starch gran- 
 ules. 
 
 Describe a starch granule ? It is depressed in the middle, 
 which is called the hilum, and it has an investing membrane 
 of nitrogenized material. 
 
 Test for starch ? It gets blue with iodine. 
 
 Is it soluble in water ? No. 
 
 Effect of boiling it with water ? It swells up. 
 
 What is the first change of starch? Into dextrine. 
 
 Is it chemical? No. 
 
 Test for dextrine ? Gets brown with iodine. 
 
 What is the next change ? Into glucose. 
 
 Give the chemical change ? Change into glucose. 
 
 Name the fluids that will digest starch? Saliva, pancre- 
 atic and intestinal juice. 
 
 Changes when subjected to them ? Changed to glucose. 
 
ALIMENTATION. 77 
 
 What is the origin of fats? Animal and vegetable king- 
 dom. 
 
 Form in which it is introduced ? Adipose tissue. 
 
 In what tissue is it not found ? Bones, teeth and fibrous 
 tissue. 
 
 What is the difference between butter and fats ? Butter 
 is softer and has no nitrogenized surrounding membrane. 
 
 Give the properties of fats ? Oil}- feel and taste, neutral 
 reaction, insoluble in water, soluble in ether and chloroform. 
 
 Action if subjected to high temperature and alkalies? 
 They are decomposed into fatty acids and glycerine. 
 
 How are soaps formed ? By the action of the fatty acids 
 on the bases. 
 
 Where are fats digested ? Small intestines. 
 
 By what fluid? Pancreatic juice. 
 
 By what are fats absorbed ? Lacteals. 
 
 Are inorganic elements of food essential to life ? Yes. 
 
 Name the most important one. Water. 
 
 How is it introduced ? With all food and drinks. 
 
 Properties of pure water? Clear, colorless, odorless fluid. 
 
 What do you usually find in water ? Organic matter and 
 inorganic salts. 
 
 Symptoms one would have if not enough water ? Thirst. 
 
 What if had too much ? Drops3 T . 
 
 Amount of water introduced per day? It is variable. 
 
 What influences the amount introduced ? The kind of 
 food and the amount eliminated. 
 
 Where do you find chloride of sodium? Everywhere 
 except in enamel of the teeth. 
 
 How is it introduced ? With food and drink. 
 
 How is it eliminated ? Urine, sweat and mucus. 
 
 Function of chloride of sodium? Gives density to the 
 plasma, aids osmosis and determines transudation. 
 
 Is there more in fluids or solids ? Fluids. 
 
78 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Why are the bones brittle in old age? There is a defi- 
 ciency in the elimination of the phosphates. 
 
 How is phosphate of lime introduced ? With nitrogen- 
 ized food. 
 
 Give its solubility? It is practically insoluble. 
 
 Found in fluids or solids ? Solids. 
 
 In what bones do you find least ? Those of sternum and 
 the ribs. 
 
 Why? The}- must be elastic to aid in respiration. 
 
 Deficiency in phosphates gives what trouble? Rickets. 
 
 How is iron combined? With the haemaglobine. 
 
 Proof of its exerting favorable influence over nutrition ? 
 Can soon notice its good effects when given an anaemic pa- 
 tient. 
 
 To what class does alcohol belong ? Non - uitrogen- 
 ized. 
 
 How is it eliminated ? It is not eliminated normally. 
 
 What was the old idea ? That it was eliminated by the 
 lungs. 
 
 Why did they think so ? They smelt it on the breath. 
 
 Present idea ? It is destroyed in the organism. 
 
 When is it eliminated ? When large amount is taken in. 
 
 What is the action of alcohol on the organism? First 
 action is a stimulant action. 
 
 What is it followed by ? Depression. 
 
 When is it not followed by depression ? In disease. 
 
 Action on the elimination of urea ? It lessens it. 
 
 On carbonic acid elimination ? It lessens it. 
 
 How does alcohol act as a food? By lessening tissue 
 waste. 
 
 Proof? There is less excrementitious products thrown off 
 during its administration. 
 
 Effect of alcohol on the temperature ? Lowers it. 
 
 How ? It lessens oxidation of tissue by being itself oxi- 
 
 
ALIMENTATION. 79 
 
 dized, and it also increases the amount of blood to the heat 
 losing area. 
 
 When do yon give alcohol? Where you have a high 
 temperature in long continued disease. 
 
 Why is it dangerous to get drunk in cold weather ? The 
 alcohol lessens the power of resistance and lowers the tem- 
 perature. 
 
 Effect of coffee on the organism ? Stimulant. 
 
 On what does its action depend? Caffein. 
 
 Action if taken in large quantities at night ? Produces 
 wakefulness. 
 
 What is its action on nutrition ? It aids it. 
 
 What is the action of tea? Same as coffee. 
 
 On what does tea depend for its action? Theine. 
 
 How does tea differ from coffee ? Tea has less of the 
 active principle. 
 
 What is theobromine ? Active principle of coco. 
 
 What is its action ? Same as coffee. 
 
 How do the inferior animals take food ? By instinct. 
 
 How does man take it in early life ? By instinct. 
 
 What is the best guide as regards the kind of food ? 
 Appetite. 
 
 When do you quit eating? When the appetite is ap- 
 peased. 
 
 Does this hold good in disease ? No. 
 
 How are excretions influenced by food ? Increased as the 
 food is increased. 
 
 What excretion is discharged in the greatest quantity? 
 Water. 
 
 Amount discharged in a day? Four and one -half 
 pounds. 
 
 Functions of water? Acts as solvent for the salts, gives 
 elasticity to cartilage, pliability to tendons, contractility to 
 muscles and density to bone. 
 
8o COMPEND OF HUMAN PHYSIOLOGY. 
 
 How can you make a theoretical diet? Introduce just 
 enough to compensate the waste. 
 
 How much carbon is discharged in twenty-four hours ? 
 Eleven ounces. 
 
 How much nitrogen ? Four and one-half ounces. 
 
 How much solid food introduced ? Two or three pounds. 
 
 How is the amount of work influenced by food ? Greatly. 
 
 Relation of the climate to the food introduced ? Cold in- 
 creases and heat retards it. 
 
 What trouble if confined to one article of food ? Become 
 emaciated. 
 
 Give illustration ? In army or on board ship this happens. 
 
 How fatten animals ? Give them a mixed diet. 
 
 What is the best diet for man ? A mixed diet. 
 
 What is the treatment for scurvy? Give fresh vegetables. 
 
 What kind of muscular tissue is best suited to man ? 
 Beef. 
 
 Why? It has the greatest nutritive powers. 
 
 Does it differ chemically from other meat? No. 
 
 Does it differ physiologically? Yes. 
 
 Proof? Changing diet increases appetite. 
 
 Are soups, extracts, etc., nutritious ? Very little. 
 
 Give the composition of roasted meats? Nitrogenized 
 matter, fats, salines and water. 
 
 What kind of bread will support life ? Brown bread. 
 
 Why? It contains a variety of principles. 
 
 What is the composition of bread? Gluten, nitrogenized 
 matter, fat, salines and water. 
 
 Why are potatoes useful articles of diet? On account of 
 the starch they contain. 
 
 What is their composition? Sugar, starch, fat, nitrogen- 
 ized matter, salines and water. 
 
 Why is milk so useful ? Has a great variety of princi- 
 ples. 
 
MASTICATION. Sr 
 
 What is the composition of butter ? Olcin and palmi- 
 tiue. 
 
 Composition of milk? Casein, fat, sugar, inorganic mat- 
 ter and water. 
 
 Composition of eggs? Albumin, fatty and inorganic mat- 
 ter and water. 
 
 What kind of diet is necessary to support life ? A mixed 
 diet. 
 
 CHAPTER XII. 
 
 MASTICATION. 
 
 What change do the inorganic principles undergo be- 
 fore introduction into the body ? A?is. None. 
 
 Do they undergo change in the body? No. 
 
 What class of food needs preparation before introduc- 
 tion ? Organic. 
 
 What is the digestive apparatus in the lowest form of 
 life ? A simple pouch w r ith a single opening. 
 
 Change as you ascend ? It becomes more complicated. 
 
 In what animals is it most complicated ? Herbivora. 
 
 Why? The food has so much waste matter. 
 
 What is the function of the colon? Receptacle for the 
 residue. 
 
 What is its length in carnivora ? Three or four times the 
 length of the body. 
 
 In omnivora ? Six or seven times the length of the body. 
 
 In herbivora ? Ten or twelve times the length of the body. 
 
 What time is a full meal in digesting ? Two to four hours. 
 
 On what does it depend ? The kind of food and the fine- 
 ness of its comminution. 
 
 What is mastication ? Chewing the food. 
 6 
 
82 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What is prehension ? Carrying the food to the mouth. 
 
 In what animals are the organs of mastication most com- 
 plicated ? Herbivora. 
 
 Why ? They take a large amount of bulky food. 
 
 In which is it simplest ? Carnivora. 
 
 In what animals is digestion most prolonged? Carniv- 
 ora. 
 
 How many teeth in each jaw? Sixteen. 
 
 Which teeth are best developed in carnivora? Canine. 
 
 Why? To tear the food. 
 
 Which in herbivora ? Molars. 
 
 Why? To grind the food. 
 
 How is the tooth divided? Root, neck and crown. 
 
 What is the crown? That part above the gums. 
 
 What is the neck ? Part between the crown and root. 
 
 What is the root? The part imbedded in the alveolar 
 processes. 
 
 What parts make up a tooth? Enamel, dentine and ce- 
 ment. 
 
 Where do you find the enamel? Covering the crown. 
 
 Describe it? Hard, white, glistening substance. 
 
 What is the cuticle ? A delicate membrane covering the 
 enamel. 
 
 How is it demonstrated? Apply a mineral acid, it sepa- 
 rates. 
 
 What does the dentine surround? The pulp cavity. 
 
 What surrounds the dentine ? Enamel. 
 
 Describe the dentine? Is like bony tissue, but has no 
 lacunae nor canaliculi. 
 
 Where do you find the cement ? Covering the root. 
 
 What is its other name ? Crusta petrosa. 
 
 Describe it? It is true bony structure. 
 
 Where do you find the pulp cavity ? On the interior of 
 the tooth. 
 
MASTICATION. 83 
 
 Give its anatomy? Blood vessels, nerves, lymphatics and 
 connective tissue. 
 
 What causes a tooth to turn black? Decomposition of 
 the pulp cavity. 
 
 Is the tooth then destroyed ? No. 
 
 Give the perfected structures of a tooth ? Enamel and 
 dentine. 
 
 Why? Because they are never reproduced if destroyed. 
 
 How many incisor teeth? Four in each jaw. 
 
 What is their shape ? Wedge. 
 
 How do they differ in the two jaws? In the [upper 
 jaw the middle teeth are largest, and in the lower, the 
 lateral. 
 
 When do the incisors appear? Seventh or eighth year. 
 
 What is their function? To divide the food. 
 
 How many canine teeth ? Two in each jaw. 
 
 What are the lower ones called? Stomach teeth. 
 
 The upper ones ? Eye teeth. 
 
 Describe a canine tooth ? Conical and pointed, and has 
 a single long root. 
 
 When do they appear ? Eleventh or twelfth year. 
 
 How many bicuspid teeth? Four in each jaw. 
 
 Describe them? Short, thick, and the crown is marked 
 by two eminences. 
 
 When do they appear ? Ninth or tenth year. 
 
 How many molars? Six in each jaw. 
 
 Names ? First, second and third molar. 
 
 Describe them ? Cube, rounded laterally and marked by 
 three eminences on the crown. 
 
 When do they first appear ? Sixth or seventh year. 
 
 The second ? Twelfth or thirteenth year. 
 
 The third ? Seventeenth to twenty-first year. 
 
 What is the last one called? Wisdom tooth. 
 
 Which jaw is broadest? Upper one. 
 
84 COMPKND OF HUMAN PHYSIOLOGY. 
 
 Position of the upper teeth to the lower? They over- 
 hang the lower. 
 
 Which jaw is movable? Lower. 
 
 Describe the lower jaw? Horse-shoe shaped, made up of 
 a horizontal body and perpendicular ramus. 
 
 Describe the articulation? Condyle, is convex with the 
 long diameter directed inward and backward. 
 
 What movements does it admit ? In every direction. 
 
 Why is the condyle not dislocated when the jaw is 
 brought forward ? The interarticular cartilage prevents it. 
 
 Name the muscles of mastication? Buccinator, tempo- 
 ral, masseter and two pterygoids. 
 
 Describe them? See Anatomy. 
 
 What muscles pull the jaw down? The elevators of the 
 os hyoides. 
 
 Which elevate it ? Temporal, masseter and the pter- 
 ygoids. 
 
 Which bring it forward ? Anterior fibres of the tempo- 
 ral, oblique fibres of the masseter and the internal pterygoid. 
 
 Which bring it back? Posterior fibres of the temporal, 
 digastric, mylo-hyoid and genio-hyoid. 
 
 Which pull it from side to side ? External and internal 
 pterygoids. 
 
 What is the nerve of mastication ? Motor root of the fifth 
 nerve. 
 
 What muscles pull the tongue forward? Posterior fibres 
 of the genio-hyo-glossus. 
 
 Which pull it backward ? Anterior fibres of the genio- 
 hyo-glossus. 
 
 Which make it concave from side to side ? The whole 
 length of the genio-hyo-glossus. 
 
 Which make it convex from side to side ? Hyo-glossus. 
 
 What is the function of the tongue in mastication ? To 
 keep the bolus between the teeth. 
 
MASTICATION. 85 
 
 What other muscle assists? Orbicularis oris. 
 
 What nerve supplies both? Facial. 
 
 What is the function of the orbicularis oris ? To close 
 the mouth. 
 
 How do you know when the food is masticated ? By the 
 sense of touch. 
 
 What other digestive process takes place in the mouth ? 
 Insalivation. 
 
 What is saliva? Secretion of the salivary glands. 
 
 Name the salivary glands ? Parotid, submaxillary and 
 sublingual. 
 
 Where do you find the parotid gland ? Behind and below 
 the ear. 
 
 What covers it externally? Parotid fascia. 
 
 Internally? Stylo-maxillary ligament. 
 
 What bounds it posteriorly ? Mastoid process of the 
 temporal bone. 
 
 Anteriorly? Ramus of the lower jaw. 
 
 What class of glands does it belong to? Compound 
 racemose. 
 
 What is its duct called ? Duct of Steno. 
 
 Where does it empty ? Opposite the second molar 
 tooth. 
 
 Give the properties of parotid secretion? Clear thin 
 fluid, coagulated by heat. 
 
 Function? To wet the bolus. 
 
 Old idea as to the cause of its secretion? Thought it 
 was due to pressure of the muscles on the gland. 
 
 Present idea ? Nervous influence. 
 
 How is the blood supply to the gland during the inter- 
 vals of mastication ? Just enough for nutrition. 
 
 During mastication ? It is very much increased. 
 
 Why ? To furnish watery element to wash out the active 
 principle. 
 
86 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What is the inhibitory nerve of the blood vessels of the 
 glands ? Corda tympani. 
 
 Where do you find the submaxillary gland ? Iu the sub- 
 maxillary triangle of the neck. 
 
 Name the duct ? Wharton's duct. 
 
 Where does it empty? On the side of the tongue. 
 
 Give the properties of the secretion? Clear fluid, gets 
 gelatinous on cooling. 
 
 Function ? Wet and coat the bolus. 
 
 When is the gland active ? All the time. 
 
 Where is the sublingual gland ? Under the tongue, one 
 on each side. 
 
 Where does the duct empty? Side of the tongue near 
 the fraenum. 
 
 Describe the fluid ? Clear, viscid, does not gelatinize on 
 cooling. 
 
 Function ? To coat the bolus. 
 
 Name the other glands that secrete saliva? Buccal, labial, 
 lingual and pharyngeal. 
 
 What do you mean by saliva ? Secretion of all the glands. 
 
 How much is secreted in a day? Two and one half to 
 three pounds. 
 
 Give its properties? Colorless, viscid, alkaline frothy 
 fluid, specific gravity 1004 to 1006. 
 
 Give its composition? Water epithelium, sulphocyanide 
 of potash, inorganic salts, and organic matter. 
 
 On what does its action depend ? Ptyalin. 
 
 How is it obtained ? By precipitating it with pure alcohol. 
 
 It digests what kind of food ? Starch. 
 
 Give the functions of saliva ? Mechanical and chemical. 
 
DEGLUTITION. 87 
 
 CHAPTER XIII. 
 
 DEGLUTITION. 
 
 Define it ? Ans. Act of swallowing. 
 
 How many acts make it up ? Three. 
 
 What parts are concerned ? Mouth, pharynx and 
 oesophagus. 
 
 Where does the pharynx begin ? Base of skull. 
 
 Where does it end ? Fifth cervical vertebra. 
 
 What separates it from the mouth ? The soft palate. 
 
 How long is it ? Four inches. 
 
 What shape is it ? Funnel. 
 
 How attached above ? Basilar process of the occipital 
 bone and the first cervical vertebra. 
 
 With what is it continuous below ? (Esophagus. 
 
 What is the shape of the anterior surface of soft palate ? 
 Concave. 
 
 Posterior surface ? Convex. 
 
 To what is the upper border attached ? To the hard 
 palate. 
 
 Where do you find the free border ? It is the inferior 
 border. 
 
 How many pillars has the soft palate ? Two. 
 
 Names ? Anterior and posterior. 
 
 What is the direction of the anterior? Downward and 
 forward, to the tongue. 
 
 Of the posterior ? Downward and backward, to the phar- 
 ynx. 
 
 What do you find between them ? The tonsils. 
 
 What is the isthmus of the fauces ? The space bounded 
 by the base of the tongue below and soft palate above. 
 
 What are its lateral boundaries ? The tonsils and pillars 
 of the soft palate. 
 
88 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Where does the oesophagus begin? Fifth cervical ver- 
 tebra. 
 
 Where end? Ninth dorsal. 
 
 What kind of a tube is it? Flaccid. 
 
 How long is it? Nine inches. 
 
 How many coats has it ? Three. 
 
 Describe the external ? Fibrous membrane. 
 
 What is the middle? Muscular fibres arranged in two 
 layers. 
 
 Describe the longitudinal fibres ? They are arranged in 
 three fasciculi above and blend into one below. 
 
 What is their function ? To shorten the tube. 
 
 Describe the circular ? They are thinner and run trans- 
 versely. 
 
 Function? Force the bolus down. 
 
 What kind of fibres are in upper part of oesophagus ? 
 Striated. 
 
 In lower part? Non-striated. 
 
 Describe the mucous membrane ? Red and vascular 
 above and pale below\ 
 
 Which act of deglutition is voluntary? First act. 
 
 Do we usually take cognizance of it? No. 
 
 Give the mechanism of the first act ? Mouth is closed, 
 bolus pushed on the tongue, which carries it back. 
 
 Which part of the second act is voluntary? First half. 
 
 What is the second act? Passing through the pharynx. 
 
 Give the mechanism? The pharynx is elevated 03- the 
 elevators of the os hyoides, and the constrictors force it 
 down. 
 
 How is the second act influenced by cutting the nerve of 
 mastication ? It interferes with it, because you can't prop- 
 erly elevate the os hyoides. 
 
 Why can't you elevate the os hyoides ? The mylo-hyoid 
 and anterior belly of the digastric are paralyzed. 
 
DEGLUTITION. 89 
 
 How influenced by cutting the facial nerve ? Interferes 
 with the elevation of the os hyoides. 
 
 Why? Stylo-hyoid and posterior belly of the digastric are 
 paralyzed. 
 
 If cut the upper root of the spinal accessory ? The sec- 
 ond part of the second act is interfered with. 
 
 Why? The constrictors of the pharynx are paralyzed. 
 
 The pharyngeal muscles are supplied by what plexus ? 
 By the pharyngeal plexus. 
 
 What forms it? The pharyngeal branch of the pneu- 
 mogastric and glosso - pharyngeal and the sympathetic 
 nerves. 
 
 Where do the motor filaments come from? From the 
 spinal accessory nerve. 
 
 How are the posterior nares protected during the second 
 act of deglutition? By contraction of the posterior pil- 
 lars of the soft palate and the superior constrictors of the 
 pharynx. 
 
 How is the glottis protected ? By the superior laryngeal 
 nerve. 
 
 Name the reflex nerves of deglutition ? Superior laryn- 
 geal and trifacial. 
 
 What becomes of respiration during the second act of 
 deglutition ? It stops. 
 
 What trouble if it does not cease ? • Food would get into 
 the air passages. 
 
 What is the third act of deglutition ? Passing through 
 the oesophagus. 
 
 Does it take place immediately? No. 
 
 Give the mechanism? The oesophagus is shortened by 
 the longitudinal fibres, and then the circular slowly force the 
 bolus down. 
 
 What is peculiar of the lower part of the oesophagus ? 
 It runs through the muscular portion of the diaphragm. 
 
90 COMPEXD OF HUMAN PHYSIOLOGY. 
 
 What is the function of the epiglottis ? To protect the 
 glottis. 
 
 Is it essential ? No. 
 
 What condition is necessary for deglutition to take 
 place? Must have something to swallow. 
 
 Is deglutition of air possible ? Yes. 
 
 CHAPTER XIV. 
 
 DIGESTION. 
 
 What is it? Ans. Liquefaction of the food. 
 
 Where does it begin ? Mouth. 
 
 What part takes place in the mouth ? Mastication and 
 insalivation. 
 
 What is the stomach ? The most dilated part of the ali- 
 mentary canal. 
 
 Where is it situated ? Epigastric and left hypochondriac 
 region. 
 
 What is the physiological definition for the stomach? 
 A receptacle for the food and a place for digestion to take 
 place. 
 
 How is the stomach divided? Surfaces, borders and ex- 
 tremities. 
 
 Name the surfaces? Anterior and posterior. 
 
 Name the borders ? Superior and inferior. 
 
 What is another name for the borders ? Greater and lesser 
 curvature. 
 
 For the extremities? Cardiac and pyloric extremities. 
 
 What is the shape of the stomach ? Bag-pipe. 
 
 Length? Fifteen inches. 
 
 Width? Five inches. 
 
DIGESTION. 91 
 
 Capacity ? About five pints. 
 
 What is in relation with the anterior surface? Dia- 
 phragm, left lobe of liver and abdominal walls. 
 
 What is in relation with the posterior? Diaphragm, 
 transverse duodenum and colon, left kidney and suprarenal 
 capsule and pancreas. 
 
 Name the coats of the stomach? Peritoneal, muscular 
 and mucous. 
 
 Describe the peritoneal ? Reflexion of peritoneum from 
 the stomach. 
 
 Name the direction of the muscular fibres? Longitud- 
 inal, circular and oblique. 
 
 Where find the longitudinal ? Along the lesser curvature. 
 
 Where find the circular ? All over the stomach. 
 
 Where are they most numerous ? At the pyloric extremity. 
 
 What do they form ? Pylorus muscle. 
 
 Where find the oblique ? Across the great extremity. 
 
 What is the thickness of the muscular coat ? One-twenty- 
 fifth inch. 
 
 What appearance has the mucous membrane when the 
 stomach is empty ? It is thrown in folds called rugae. 
 
 What becomes of these rugae during digestion? They 
 become obliterated. 
 
 What appearance has the mucous membrane when 
 washed? It is marked by numerous pits. 
 
 Where is the mucous membrane thickest ? At the py- 
 loric extremity. 
 
 What kind of epithelium lines it ? Columnar. 
 
 What glands do you find in it? Acid and peptic glands. 
 
 Where do you find the peptic glands ? Near the cardiac 
 opening. 
 
 Where find the acid glands? Throughout the stomach. 
 
 The secretion in what part of the stomach is acid? 
 Greater pouch. 
 
92 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What lines the peptic glands ? Peptic cells. 
 
 What lines the secreting part of the acid glands ? Peptic 
 cells. 
 
 What lines the acid part? Acid cells. 
 
 What is the function of acid glands ? To secrete hydro- 
 chloric acid. 
 
 When is pepsin produced ? All the time. 
 
 When is acid produced? When food is in the stomach. 
 
 What do peptic cells produce? Zymogen. 
 
 What changes it into pepsin ? The hydrochloric acid. 
 
 What lines the excreting part of the gland? Columnar 
 epithelium. 
 
 What is the color of a peptic cell? Light pink. 
 
 Of the acid cell? Dark. 
 
 In what period of life do you find closed follicles ? In 
 children. 
 
 Where are they most abundant? In the great curYature. 
 
 What reaction is the stomach during the intervals of di- 
 gestion ? Alkaline. 
 
 During digestion, how is it? Acid. 
 
 What is gastric juice? The secretion of the glands of 
 the stomach. 
 
 When is it discharged ? During digestion. 
 
 How is it obtained ? By making a fistula. 
 
 Name three ways in which you could obtain a digestive 
 fluid? Mixing acid and pepsin, making a gastric fistula, or 
 making an infusion of the mucous membrane of the stomach. 
 
 What part of the mucous membrane would you select to 
 make an infusion? The pyloric extremity. 
 
 Why ? The peptic glands are found there. 
 
 What two elements are used to make it artificially ? 
 Acid and pepsin. 
 
 How can you get pure gastric juice ? By making a fistula. 
 
 What is the best kind of food to introduce ? Savon 7 food. 
 
DIGESTION. 93 
 
 How should it be introduced? By the mouth. 
 
 Why ? It mixes with saliva which aids the flow of gastric 
 juice, and passing through the natural channel also aids it. 
 
 Why not use a local stimulant ? If articles are given 
 which the animal relishes it aids the flow. 
 
 What is the best stimulant ? Natural food. 
 
 What influence has saliva ? It increases it. 
 
 When does the secretion of gastric juice cease ? When 
 the food is of a pultaceous mass. 
 
 How much gastric juice secreted in a day ? Six to four- 
 teen pounds. 
 
 What becomes of it ? That not used in digestion is re- 
 absorbed. 
 
 What part do the inorganic salts play in digestion ? 
 Very little. 
 
 Give the properties of gastric juice? Clear amber fluid, 
 non-viscid, acid in reaction, specific gravity 1005 to 1009. 
 
 Give its composition? Water, acid, pepsin, chlorides and 
 phosphates. 
 
 What is its active principle ? Pepsin. 
 
 When is it produced ? All the time. 
 
 By what ? Epithelium of the glands. 
 
 Is it a secretion ? Yes. 
 
 Why ? It is manufactured in a gland. 
 
 To what class of secretions does it belong ? Transitory. 
 
 What is the object of that class? To aid in digestion. 
 
 How do you obtain pepsin ? Make an acidulated infusion 
 of the mucous membrane. 
 
 Give its properties ? Grayish translucent scales of char- 
 acteristic odor. 
 
 In what is it soluble ? Water and weak alcoholic solutions. 
 
 What kind of acid has gastric juice ? Hydrochloric. 
 
 What part of the gastric juice is necessary for digestion ? 
 Acid and pepsin. 
 
94 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Could there be too much pepsin ? No. 
 
 Could there be too little ? Yes. 
 
 Could there be too much acid ? Yes. 
 
 What would you do for it? Give an alkali. 
 
 When would you give it ? After meals. 
 
 What action would it have if given before meals ? It 
 would increase the acidity. 
 
 If there is too little acid, what do ? Give them an acid 
 after meals. 
 
 Why give it after the meal ? To make up for the de- 
 ficiency. 
 
 Why think you need no special acid? Get the same 
 effect from any of them. 
 
 In what way does chloride of sodium aid digestion? 
 It aids the flow of gastric juice. 
 
 What class of food is digested in the stomach ? Nitro- 
 genized. 
 
 Which is the most important one ? Musculine. 
 
 Where is it digested ? Small gut. 
 
 What is the action of gastric juice on meat ? It digests 
 the fibrous tissue. 
 
 Where is myosin digested? Small gut. 
 
 Where is albumin digested ? Stomach. 
 
 What kind of food is easiest digested? Whipped eggs. 
 
 What is the action of gastric juice on fibrin casein and 
 nitrogenized vegetables ? It digests them. 
 
 Action on cane sugar? Digests it. 
 
 What fluids digest cane sugar? Gastric and pancreatic juice. 
 
 What part of the gastric juice ? The acid. 
 
 What are peptones? Products of stomachic digestion. 
 
 Different kinds ? Acid albumin, or albuminate, and pro- 
 peptone, or hemialbumose, and true peptones. 
 
 How do they differ from albumin? They are osmatic 
 and not coagulated by heat as albumin is. 
 
DIGESTION. 95 
 
 If albumin is injected into the veins, what becomes of it? 
 It is rejected by the kidneys. 
 
 What if cane sugar is injected into the veins ? Rejected 
 by the kidneys. 
 
 What becomes of albuminose if injected into veins? It 
 is deposited. 
 
 How many fluids digest nitrogenized principles? Two. 
 
 Name them ? Gastric and pancreatic juice. 
 
 Mostly digested by which one? Gastric juice. 
 
 What is the action of gastric juice on starch ? It digests 
 the nitrogenized membrane. 
 
 What fluids digest starch? Saliva, pancreatic and intes- 
 tinal fluids. 
 
 The greater part is digested by which one ? Saliva. 
 
 What is the action of gastric juice on fats? Digests the 
 nitrogenized membrane. 
 
 Where are fats digested ? Small gut. 
 
 What is the time of stomachic digestion ? Two to four 
 hours. 
 
 On what does it depend ? On the kind and amount of 
 food. 
 
 What food is easiest digested? Eggs, milk, fish, tripe, 
 etc. 
 
 What condition is most favorable for digestion ? A mod- 
 erate amount of exercise. 
 
 What retards it ? Fatigue. 
 
 Name the motor nerve of the walls of the stomach ? 
 Pneumogastric. 
 
 Proof? Cut it and have paralysis of the stomach. 
 
 Name the inhibitory nerve to the blood vessels ? Pneu- 
 mogastric. 
 
 If the pneumogastric be cut, how is the blood supply ? 
 Lessened. 
 
 If stimulated? Increased. 
 
96 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Why will cutting it stop digestion ? It cuts off the blood 
 and paralyzes the walls of the stomach. 
 
 What is the effect of cutting the sympathetic ? It in- 
 creases the blood supply. 
 
 If stimulate the sympathetic? Lessens the blood sup- 
 ply. 
 
 What change is there in the position of the stomach 
 when it is distended? The anterior surface becomes su- 
 perior. 
 
 Why does it cause dyspnoea? Due to pressure on dia- 
 phragm. 
 
 Where does the bolus enter the stomach ? Cardiac ex- 
 tremity. 
 
 Course ? Along the greater curvature and then back along 
 the lesser. 
 
 Time it takes ? Three minutes. 
 
 Why are the walls of the stomach paralyzed when the 
 pneumogastric nerve is cut? It is the motor nerve of the 
 stomach. 
 
 What is its origin? Between the corporas olivaria and 
 restiformia. 
 
 In what animals is regurgitation of food common ? Her- 
 bivora. 
 
 Is it physiological in man ? No. 
 
 Give the mechanism? Relaxation of the cardiac extrem- 
 ity followed by contraction of the stomach. 
 
 What is emesis ? Vomiting. 
 
 How are emetics divided? Centric and local. 
 
 What is a local emetic ? One that acts by its presence in 
 the stomach. 
 
 What is a centric one ? It acts through the nervous sys- 
 tem by an action on the nerve centers. 
 
 What is the first thing in emesis ? Deep inspiration. 
 
 What is next? Fixation of the diaphragm. 
 
SMALL INTESTINES. 97 
 
 How is the diaphragm fixed? By closure of the 
 glottis. 
 
 What part of the stomach relaxes? The cardiac ex- 
 tremity. 
 
 What part contracts ? The rest of it. 
 
 What is the last act in emesis ? Expulsion. 
 
 CHAPTER XV. 
 
 SMALL INTESTINES. 
 
 What is the most important part of the digestive system ? 
 Ans. The small intestines. 
 
 Why is it so called ? Because there is a larger one. 
 
 Where does the small gut begin ? At the stomach. 
 
 Where end? Right iliac fossa. 
 
 How long is it ? About twenty feet. 
 
 How is it divided ? Duodenum, jejunum and ileum. 
 
 Why was the duodenum so called ? It is the length of 
 the breadth of twelve fingers. 
 
 How long is it ? Nine inches. 
 
 What shape is it ? Horse-shoe. 
 
 How is its concavity directed ? To the left. 
 
 What is found in it ? The head of the pancreas. 
 
 How is the duodenum divided ? Into ascending, descend- 
 ing and transverse portion. 
 
 What is the direction of the first part? Upward and 
 backward. 
 
 The relation of peritoneum to the first part ? Completely 
 surrounds it. 
 
 Give the relation of the first part ? Above is the liver 
 and neck of the gall-bladder, in front is the great omentum 
 7 
 
98 COMPEND OF HUMAN PHYSIOLOGY. 
 
 and abdominal walls, behind is the lesser omentum and its 
 vessels. 
 
 What is the direction of the second part ? Down to the 
 fourth lumbar vertebra. 
 
 Relation to the peritoneum? It is behind the peritoneum. 
 
 Give the relation of the second part ? In front is the 
 colon, behind, the inferior vena cava and kidney and ductus 
 communis choledochus, on the right the ascending colon, on 
 the left the head of the pancreas. 
 
 What duct empties into it? Ductus communis chole- 
 dochus. 
 
 Where ? At the posterior and internal aspect. 
 
 Where does the third part begin ? Upper border of the 
 fourth lumbar vertebra on the right side. 
 
 What is its course ? Transversely across the third lumbar. 
 
 Where does it end ? L,eft side of the second lumbar ver- 
 tebra. 
 
 How long is it? Half the length of the duodenum. 
 
 Relation of the peritoneum ? In front and on the sides. 
 
 What part of the duodenum is most firmly fixed ? Third 
 part. 
 
 Which is most movable ? First part. 
 
 What is the jejunum? The second part of the small gut. 
 
 Why was it so called ? It was found empty after death. 
 
 What is its length ? A little less than two-fifths of the 
 entire length. 
 
 Where does it begin ? Left side of the second lumbar 
 vertebra. 
 
 Where end ? At the ileum. 
 
 What does ileum mean ? Twisted. 
 
 How long is the ileum ? A little more than two-fifths of 
 the entire length. 
 
 Name the coats of the small gut? Serous, muscular and 
 mucous. 
 
SMALL INTESTINES. 99 
 
 Describe the external? A serous membrane that binds 
 the guts to the vertebral column. 
 
 What is the mesentery ? The serous membrane that 
 binds the guts to the spinal column. 
 
 Where does it begin ? At the second lumbar vertebra. 
 
 Where end ? Right iliac fossa. 
 
 How many borders has it ? Two. 
 
 Name them ? Free and attached. 
 
 Length of each ? Free is eighteen feet and attached is 
 six inches. 
 
 What is the function of the mesentery? To bind the 
 guts to the spinal column and to transmit the blood vessels 
 and lymphatics. 
 
 What is the middle coat of the guts ? Muscular. 
 
 What is the function of the longitudinal fibres ? To 
 shorten the gut. 
 
 Of the circular ? To constrict and force the bolus down. 
 
 Where are they most numerous ? In the upper part. 
 
 What is the difference in the mucous coat of the stomach 
 and small gut ? It is thinner in the gut. 
 
 Where is it thickest ? In the duodenum. 
 
 Name the glandulas elements of the small gut ? Valvu- 
 lse conniventes, glands of Brunner, follicles of Lieberkuhn, 
 single and agminated glands and intestinal villi. 
 
 Where do you find Brunner's glands ? In the upper half 
 of the duodenum. 
 
 What kind of glands are they ? Compound racemose. 
 
 As regard the coats of the gut, where do you find them ? 
 In the sub-mucous coat. 
 
 What size are they ? One-tenth inch. 
 
 Give their physiological anatomy ? A large number of 
 little follicles all centering into one duct. 
 
 What kind of fluid do they secrete ? Clear, viscid, 
 alkaline fluid. 
 
IOO COMPEND OF HUMAN PHYSIOLOGY. 
 
 What is its function ? It is not known. 
 
 Where do you find the valvulae conniventes ? From the 
 middle of the duodenum to the lower third of the ileum. 
 
 How far around do they extend ? One-half to one-third 
 the way around. 
 
 What do you find between them ? Connective tissue and 
 blood vessels. 
 
 What is their function ? To increase the surface exposed. 
 
 How much does it increase it in the jejunum ? It doubles 
 it. 
 
 How much in the ileum? One-sixth. 
 
 Where do you find the follicles of Leiberkuhn ? Through- 
 out the large and small gut. 
 
 What shape are they ? Tubular. 
 
 What part is not occupied by these glands? Parts occu- 
 pied by other glands. 
 
 Give their anatomy ? They are simple inversions of the 
 mucous membrane. 
 
 How do they terminate ? In a single or double blind ex- 
 tremity. 
 
 How long are they? One seventy-fifth inch. 
 
 What is their diameter ? One three hundred and sixtieth 
 inch. 
 
 Function? To secrete intestinal juice. 
 
 Where do you find the viUi ? Throughout the small gut. 
 
 They have chiefly to do with what ? Absorption. 
 
 On which side of the ileo-ccecal valve do you find them ? 
 On the iliac side. 
 
 What appearance do they give the mucous membrane ? 
 Velvety. 
 
 Where are the villi most numerous ? In the duodenum. 
 
 How many to the square inch in the small gut? 7000. 
 
 What shape are they in the human ? Flattened cones. 
 
 Describe them in the duodenum. Flat and short. 
 
SMALL INTESTINES. IOI 
 
 In the jejunum. They are longer. 
 
 In the ileum. Are shorter. 
 
 What form predominates in the upper part of the gut ? 
 The short, flat variety. 
 
 Where are they longest ? In the jejunum. 
 
 How long are they? One-thirtieth to one-twentieth 
 inch. 
 
 What is their diameter at the base ? One-seventieth to 
 one hundred and twentieth inch. 
 
 How are they formed ? By an eversion of the mucous 
 membrane. 
 
 Describe the membrane ? A structureless basement mem- 
 brane covered by epithelium. 
 
 Where do you find the epithelium ? On the outside. 
 
 What kind ? Columnar. 
 
 Where do the arteries enter the villus ? At the base. 
 
 How many ? Six to twelve. 
 
 How do they terminate ? In capillary loops. 
 
 Describe the veins ? At first there are four or five, but they 
 all terminate in one. 
 
 Direction of the muscular fibres of the villi ? Longitu- 
 dinal. 
 
 Describe them ? They run half way between the center 
 and periphery of the gland. 
 
 What is their function ? To shorten the villi. 
 
 How do lymphatics begin ? In lymph spaces. 
 
 What are they called? Lacteals. 
 
 Why ? They carry a milk-like fluid. 
 
 What fluid is it? Emulsified fats. 
 
 Where find the solitary glands ? Throughout the large 
 and small gut. 
 
 Where do you find the agminated glands ? In the ileum. 
 
 What is their other name ? Peyer's patches. 
 
 Where are they found? Mostly in the ileum. 
 
]02 COMPKND OF HUMAN PHYSIOLOGY. 
 
 On what part of the gut are they ? Opposite the attach- 
 ment of the mesentery. 
 
 Are they always present ? They are. 
 
 What shape are they ? Oblong. 
 
 Length ? Three-fourths to one and one-half inch. 
 
 Width? One-half to three-fourths inch. 
 
 Where are they largest? In the lower part of the 
 ileum. 
 
 How many are there ? Eighteen to twenty. 
 
 Where may they be found ? In the jejunum and ileum. 
 
 How many varieties are there ? Two. 
 
 Name them? Smooth and prominent. 
 
 Describe the more prominent variety ? They are covered 
 by mucous membrane which is thrown in folds. 
 
 What is the arrangement of the valvulae conniventes near 
 their border ? They stop. 
 
 Why are Peyer's patches not always found ? The smooth 
 variety are overlooked. 
 
 What kind do you have in feeble persons? Smooth 
 variety. 
 
 What appearance have the villi on the large kind ? 
 They are large and prominent. 
 
 What is the shape of the follicles ? Pear-shaped. 
 
 How is the pointed extremity directed ? Toward the in- 
 side of the gut. 
 
 What is the peculiarity of the mucous membrane just 
 above the follicle ? Has a small opening in it. 
 
 Do you find this in the small ones ? No. 
 
 What is the diameter of the follicles? One seventy-fifth 
 to one-twelfth inch. 
 
 Describe the surrounding membrane? Simple homoge- 
 neous membrane. 
 
 What does it contain? Semi-fluid grayish contents, cells, 
 blood-vessels and lymphatics. 
 
SMALL INTESTINES. 103 
 
 What is the arrangement of the blood-vessels ? A net- 
 work around each follicle. 
 
 What part of their anatomy has not been demonstrated ? 
 Lymphatics. 
 
 Why is it thought that they contain lymphatics ? The 
 absorption of fats can be accounted for in no other way. 
 
 What is the function of Peyer's patches ? Has to do with 
 absorption. 
 
 In what trouble are they ulcerated ? Typhoid fever. 
 
 Why are the mesenteric glands enlarged? Because the 
 lymphatics coming from Peyer's patches pass through them. 
 
 Name the last digestive fluid ? Intestinal juice. 
 
 What produces it ? The glands of the small intestine. 
 
 How is it obtained ? Empty a part of the gut and ligate 
 each end and allow the fluid to collect. 
 
 Give its properties ? Viscid fluid of rose tint and alkaline 
 reaction. 
 
 How much solid constituents has it ? Five to five and 
 one-half per cent. 
 
 The digestion of what food is completed by it ? Nitro- 
 genized food and starch. 
 
104 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XVI. 
 
 PANCREAS. 
 
 What does pancreas mean ? Ans. All flesh. 
 
 Where is it found? In the abdominal cavity, opposite the 
 second lumbar vertebra. 
 
 What other names has it ? Sweet bread or abdominal sal- 
 ivary gland. 
 
 What shape is it ? Wedge. 
 
 How is it divided? Head, body and tail. 
 
 How long is it? Seven inches. 
 
 Weight? Four or five ounces. 
 
 Where do you find the head ? In the concavity of the 
 duodenum. 
 
 Where find the tail ? In apposition with the spleen. 
 
 Name the surfaces ? Anterior and posterior. 
 
 Borders ? Superior and inferior. 
 
 What grooves the upper border ? The splenic vessels. 
 
 What grooves the lower border? Superior mesenteric 
 artery. 
 
 What kind of a gland is the pancreas ? Compound race- 
 mose. 
 
 Where does the duct begin ? At the tail. 
 
 How many at the beginning ? Two. 
 
 Where do they unite ? At the junction of the large third 
 with the middle. 
 
 Nearest which surface is the duct ? Anterior. 
 
 Destination of the duct? Empties into the ductus com- 
 munis choledochus. 
 
 When is the gland active ? All the time. 
 
 How can you obtain the fluid? Make a fistula in the 
 duct. 
 
 How much is secreted in an hour ? One hundred grains. 
 
PANCREAS. 105 
 
 Give its properties ? Viscid, slightly opaline fluid, specific 
 gravity 1040. 
 
 Give its composition ? Water, organic matter, chlorides, 
 phosphates and carbonates. 
 
 Name the active principles? Amylopsin, tripsin and 
 steapsin. 
 
 What does each digest ? Tripsin digests the nitrogenized 
 food, steapsin the fats and amylopsin the starch and cane 
 sugar. 
 
 How do these substances differ from albumin? Their 
 dried alcoholic precipitate is soluble in water, while that of 
 albumin is not. 
 
 What is the action of pancreatic juice on starch ? 
 Changes it to sugar. 
 
 What is the action on cane sugar ? Changes it to glu- 
 cose. 
 
 On nitrogenized food ? Digests it. 
 
 On fats ? Emulsifies them. 
 
 Name the only fluid that will form a complete emulsion ? 
 Pancreatic juice. 
 
 What is an emulsion ? Fine particles of fat held in sus- 
 pension by some gummy substance. 
 
 By what is it absorbed ? Lacteals. 
 
 What kind of action takes place in the digestion of fats ? 
 Mechanical. 
 
 What is the action of pancreatic juice on fats outside of 
 the organism ? Decomposes them into fatty acid and glyc- 
 erine. 
 
 What would you suspect if called to see a patient with 
 fatty diarrhoea? That there was some trouble with the 
 pancreatic juice. 
 
106 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XVII. 
 
 BILE. 
 
 What is bile? Arts. A secretion and excretion of the 
 liver. 
 
 What part is a secretion ? Biliary salts and sugar. 
 
 Which is an excretion? Cholesterin. 
 
 Why is it discharged continuously ? To get rid of cho- 
 lesteritis. 
 
 Is bile essential to life ? It is. 
 
 How long will a dog live when not discharged into the 
 small gut ? Forty days. 
 
 With what symptoms would he die ? Symptoms of 
 inanition. 
 
 How many functions has bile ? Three. 
 
 Name them ? Nature's purge and disinfectant and to aid 
 in digestion. 
 
 What is jaundice? A deposit of bile pigment in the 
 tissues. 
 
 Name the different kinds? Hematogenous and hep- 
 atogenous. 
 
 Cause of hematogenous variety? Impoverished or 
 poisoned condition of the blood. 
 
 What would be the treatment for it? To improve the 
 condition of the blood. 
 
 What is the cause of hepatogenous variety ? Where it 
 is due to obstruction of the bile duct. 
 
 What would be the treatment ? To remove the obstruc- 
 tion. 
 
 What is peristalsis ? A worm-like movement of the gut 
 from above downward. 
 
 What is anti-peristalsis? Worm-like movement from 
 below upward. 
 
LARGE INTESTINES. 107 
 
 What excites the regular movement of the guts ? The 
 presence of bile. 
 
 Where is the contraction most vigorous ? In the upper 
 part. 
 
 Why ? There is more bile there. 
 
 What is the function of the gases of the small gut ? To 
 keep the walls distended. 
 
 What causes the bowels to act after death ? Want of 
 oxygen in the centers acts as an irritant. 
 
 What is the motor nerve of the small gut ? Sympathetic. 
 
 Which is the inhibitory nerve ? Pneumogastric. 
 
 How are the movements influenced by cutting the pneu- 
 mogastric nerve ? They are not affected. 
 
 How is the blood supply influenced ? Lessened. 
 
 What are the symptoms if the great splanchnic is cut ? 
 Loss of motion of the guts. 
 
 How is the blood supply influenced ? It is increased. 
 
 CHAPTER XVIII. 
 
 LARGE INTESTINES. 
 
 How long are they ? Arts. Four to six feet. 
 
 Where do they begin ? Right iliac fossa. 
 
 Where end ? At the anus. 
 
 What is their position to the small guts ? Surround the 
 small gut. 
 
 What is the largest part of the large intestine ? Caecum. 
 
 What are some other names for it ? Caput coli or blind 
 pouch. 
 
 Where do you find it? In the right iliac fossa. 
 
 Size ? Two and one-half to three and one-half inches long. 
 
108 COMPEND OF HITMAN PHYSIOLOGY. 
 
 What empties into it ? The ileum. 
 
 What is the relation of the peritoneum to it? It is in 
 front and on the sides. 
 
 What is typhlitis ? Inflammation of the caecum. 
 
 What is perityphlitis ? Inflammation of the peritoneum 
 around the caecum. 
 
 Where do you find the right colon? On the right side, 
 extending from the caecum to the liver. 
 
 What other name has it ? Ascending colon. 
 
 Relation of peritoneum to it ? Is in front and on the sides. 
 
 Where does the right colon end ? Under the liver. 
 
 Name the flexure ? Hepatic flexure. 
 
 What is the arch of the colon ? The transverse colon. 
 
 Relation of peritoneum? Surrounds it. 
 
 Where do you find the splenic flexure ? In opposition 
 with the spleen. 
 
 Relation of peritoneum to left colon ? In front and on 
 the sides. 
 
 Where does the left colon end ? At the crest of the ileum. 
 
 What is the shape of the sigmoid flexure ? Like the 
 italic letter S. 
 
 Relation of the peritoneum to it ? Surrounds it. 
 
 What is the smallest part of the large gut ? The opening 
 of the sigmoid flexure into the rectum. 
 
 Where does the faeces accumulate ? In the sigmoid flexure. 
 
 What is the length of the rectum ? Nine inches. 
 
 Why is it called rectum ? It is comparatively straight. 
 
 Where does it begin ? At the left sacro-iliac symphysis. 
 
 Where does it end ? A half inch in front of the coccyx. 
 
 How is the rectum divided ? First, second and third por- 
 tion. 
 
 What is the length of the first part ? Half the length of 
 the entire rectum. 
 
 Relation of the peritoneum to this part? Surrounds it. 
 
LARGE INTESTINES. 109 
 
 Give the relations of the first part? Behind pyriformis 
 muscle and origin of the sacral plexus of nerves, in front 
 by the bladder in the male and uterus and its appendages in 
 the female. 
 
 Describe the second part? Runs downward in the con- 
 cavity of the sacrum. 
 
 Relation of peritoneum to it? Covered in front on the 
 upper part. 
 
 Relation of the second part ? In front by male, base of 
 the bladder vesicula seminales, vas deferens, in the female 
 the posterior wall of the vagina. 
 
 Describe the third part ? Runs backward and terminates 
 a half inch from the coccyx in the anus. 
 
 Where do you find the ilio-csecal valve ? Between ileum 
 and caecum. 
 
 How is it formed? By folds of the walls of the gut. 
 
 What is the direction of the slit? Horizontal. 
 
 How many lips has it ? Two. 
 
 How is their concave surface directed? Toward the ileum. 
 
 What is the effect of pressure on the csecal side ? Closes 
 the valve. 
 
 On the iliac side ? It opens it. 
 
 Give the anatomy of the valve ? Fibrous tissue and cir- 
 cular muscular fibres, all covered by mucous membrane. 
 
 What keeps it from pulling out ? It is continuous with 
 the muscular coat of the gut. 
 
 What is the function of the valve ? To keep the faeces 
 out of the small gut. 
 
 Name the coats of the large gut ? Peritoneal, muscular 
 and mucous. 
 
 Where is the peritoneal coat complete ? Transverse colon 
 and sigmoid flexure. 
 
 What is the arrangement of the muscular fibres ? Cir- 
 cular and longitudinal. 
 
IIO COMPEND OF HUMAN PHYSIOLOGY. 
 
 Which layer is external ? The longitudinal. 
 
 In how many bands is it arranged ? Three. 
 
 Position in the ascending colon ? Anterior and two latter 
 posterior. 
 
 What is their position in the transverse colon ? The an- 
 terior band becomes inferior and the others posterio, superior 
 and inferior. 
 
 How are they in the descending colon ? Same as in the 
 ascending. 
 
 How, in the rectum ? Two become blended into one, so it 
 leaves two bands. 
 
 How, in the last part of the rectum? They all blend into 
 one and surround the rectum. 
 
 Why does the large gut appear puckered? The longi- 
 tudinal fibres are shorter than the gut. 
 
 Describe the circular fibres in the caecum and colon ? 
 Form only a thin layer. 
 
 What is their arrrangement in the rectum ? Form the 
 sphincter muscle. 
 
 How does the mucous membrane of the large gut differ 
 from that of the small? Paler, thicker, firmer and more 
 closely attached. 
 
 Name the glands of the large intestine ? Follicular and 
 utricular. 
 
 Describe the mucous coat in the last part of the rectum ? 
 It is loose and thrown into folds. 
 
 Describe the veins at that part ? They are very numerous. 
 
 What is dilatation of them called ? Piles or haemorrhoids. 
 
 Have they any valves ? No. 
 
 What other outlet besides the liver has the veins of the 
 guts ? The internal iliac vein. 
 
 Which hemorrhoidal unites with it ? The middle one. 
 
 Give the characters of the fluid secreted by the glands 
 of the large gut. A glairy mucus. 
 
LARGE INTESTINES. ill 
 
 Has it any influence over digestion ? It has not. 
 
 Where are the contents of the intestines most fluid ? 
 Small gut (duodenum). 
 
 Where most consistent ? Sigmoid flexure. 
 
 What is its color in the jejunum ? A bright yellow. 
 
 What color in the sigmoid flexure? Dark brown. 
 
 What causes it to change ? Absorption of the watery 
 material. 
 
 What is the contents of the small guts called ? Chyme. 
 
 To what is fermentation in the intestinal canal due? To 
 the action of micro-organisms. 
 
 How many micro-organisms has Pasteur isolated ? Sev- 
 enteen different kinds in the mouth. 
 
 What is the action on albumin ? Dissolves it. 
 
 What kind of fermentation do you have in the guts ? 
 Putrefactive. 
 
 Name some substance resulting from intestinal fermen- 
 tation? Indol, skatol, phenol, etc. 
 
 Name some drugs that will arrest the action of indol, etc.? 
 Calomel, salicylic acid. 
 
 What is the contents of the large gut called ? Faeces. 
 
 How does it differ from that of the small ? In odor and 
 color. 
 
 On what does the color depend ? Bile. 
 
 How much fleeces eliminated in a day ? Four and one- 
 half ounces. 
 
 On what does the consistence depend ? On the length of 
 time it has been in the gut. ' 
 
 Name some of the micro-organisms of the large gut ? 
 Bacterium coli commune, bacterium lactis aerogenes, the 
 large bacilli of Bienstock, etc. 
 
 What is excretin? A crystalline substance extracted 
 from the faeces. 
 
 What is stercorine ? Modified cholesterin. 
 
112 COMPEND OF HUMAN PHYSIOLOGY. 
 
 When is cholesterin discharged from the rectum ? Dur- 
 ing fasting. 
 
 Putrefactive process is most marked in what gut ? Large 
 gut. 
 
 What gives the faecal odor ? The products of intestinal 
 putrefaction. 
 
 How can this be produced out of the organism ? By the 
 action of pancreatic juice on albuminoids. 
 
 What is the action of pancreatic juice in an alkali me- 
 dium on tripsine peptones ? Changes it into leucin, tyro- 
 sin, hypoxan thine and asparaginic acid. 
 
 What if the action carried further ? Forms indol, skatol, 
 and phenol. 
 
 How does the contraction of the large gut differ from 
 that of the small? It is less vigorous and rapid. 
 
 What is the function of the longitudinal fibres ? To 
 shorten the gut. 
 
 What causes matter to pass through the caecum and 
 ascending colon? The pressure from the small gut. 
 
 CHAPTER XIX. 
 
 DEFECATION. 
 
 Define it? Am. Expulsion of faecal matter from the 
 rectum. 
 
 How often does it occur ? Once a day. 
 
 What is the best time to defaecate ? In the morning. 
 
 Why ? On arising the blood supply to the guts is increased 
 and also the movements of the gut. 
 
 Where does the faecal matter accumulate? In the sig- 
 moid flexure. 
 
DEFECATION. 113 
 
 What causes the desire to evacuate ? Pressure on the 
 nerves in passing into the rectum. 
 
 How can you prove that faeces does not accumulate in 
 the rectum? The rectum is found empty. 
 
 What is the narrowest part of the large gut ? Opening 
 from sigmoid flexture to rectum. 
 
 What is it called? Sphincter O'Beirne. 
 
 What do you mean by a figured evacuation ? Where the 
 faeces is moulded to the shape of the gut. 
 
 What is tenesmus ? Frequent and painful desire to evac- 
 uate. 
 
 What is tormina ? Colicky pains. 
 
 Describe the first part of evacuation ? Faecal matter is 
 forced through the sphincter O'Beirne. 
 
 What resists the matter ? The sphincter muscle. 
 
 How is it dilated ? By the pressure of the faeces. 
 
 What is the function of the levator ani ? To assist in 
 dilatation of the sphincter. 
 
 What other muscles help perform the act ? The abdom- 
 inal muscles. 
 
 Give the mechanism ? Anus is dilated, rectum becomes 
 almost straight and the faeces is forced down. 
 
 What interrupts the discharge? Contraction of the 
 sphincter ani. 
 
 Is the internal sphincter voluntary ? It is not. 
 
 Name the gases of the stomach? Oxygen, hydrogen, 
 nitrogen and carbonic acid gas. 
 
 Name the gases of the small intestine? Hydrogen, ni- 
 trogen and carbonic acid gas. 
 
 In large gut? Hydrogen, nitrogen, carbonic acid and car- 
 burretted hydrogen. 
 
 What is their origin? They are given off during the 
 fermentation of the food. 
 
 What is their function ? To keep the guts distended. 
 
114 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XX. 
 
 ABSORPTION. 
 
 What is digestion ? Ans. Liquefaction of the food. 
 
 Where does it begin ? In the mouth. 
 
 Where does it end ? In the small intestines. 
 
 What is the first object of digestion? To liquefy the 
 food. 
 
 What is the second object? To prepare it for absorption. 
 
 What is the first transformation ? Starch into sugar. 
 
 What is absorption ? Getting into the blood and lymph. 
 
 Where does it begin ? In the mouth. 
 
 Where end ? In the rectum. 
 
 Proof of its taking place in the mouth ? The chewing of 
 tobacco makes some persons sick. 
 
 Absorption is carried on by what vessels? Veins and 
 lymphatics. 
 
 What does the blood absorb? All that will form a ho- 
 mogeneous mass with the blood. 
 
 What is absorbed by the lymphatics? All the rest. 
 
 Proof of absorption in the rectum? Get physiological 
 effects from an enema. 
 
 Where does the greater part take place? In the small 
 gut. 
 
 What change does the alimentary mass undergo in pass- 
 ing down the alimentary canal ? It becomes more consist- 
 ent and the biliary salts disappear. 
 
 Why are lymphatics hard to demonstrate ? Their walls 
 and valves are weak. 
 
 How are they demonstrated? By injecting them with 
 mercury. 
 
 Have they been discovered in all tissue ? No. 
 
 How do lymphatics arise ? In lymph spaces. 
 
ABSORPTION. 115 
 
 What do you mean by lymph spaces ? Spaces between 
 the fibres. 
 
 What is their other name? Juice-canals. 
 
 How is nutrient matter applied to the parts ? By transu- 
 dation through the walls of the capillaries. 
 
 How does effete matter pass off? Carried by lymphatics 
 from the lymph spaces to the veins. 
 
 What tissues receive nutriment through lymph spaces ? 
 Cornea of the eye and fibrous membranes. 
 
 How does the fluid differ from lymph ? It has no lymph 
 corpuscles. 
 
 Relation of lymphatics to blood vessels ? They are in 
 very close relation. 
 
 Do lymphatics vary much in size ? No. 
 
 What is the size of the smallest that have been demon- 
 strated ? One three-hundredth inch. 
 
 How do they differ from blood vessels ? Their walls are 
 thinner. 
 
 Which lymphatics are most numerous? The smallest. 
 
 How are they arranged in the skin ? Into a superficial 
 and deep plexus. 
 
 Which plexus has the largest lymphatics ? The deep one. 
 
 What are deep lymphatics ? Those accompanying deep 
 veins. 
 
 What lymphatics have no valves ? The smallest. 
 
 What is the cause of the beaded appearance of lymphat- 
 ics ? The valves. 
 
 What is the course of lymphatics ? Generally direct. 
 
 How do they anastomose ? By bifurcation. 
 
 Lymphatics resemble what vessels ? Veins. 
 
 What are the largest that pass from the skin? One 
 twenty-fifth to one-twelfth inch. 
 
 On what does the caliber of the vessel depend ? On the 
 pressure of the contained fluid. 
 
Il6 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Where are lymphatics most numerous on the skin? 
 Scalp, biparietal suture, palms of the hands and soles of the 
 feet. 
 
 Where do they attain their highest degree of develop- 
 ment ? In the median line of the scrotum. 
 
 Give the arrangement of lymphatics on mucous mem- 
 branes ? A double plexus, as in the skin. 
 
 In what mucous membrane are they most numerous? 
 Mouth, lips, nares, vagina, penis. 
 
 Give their origin and arrangement in the lungs ? They 
 arise in the walls of the air cells and form a plexus around 
 each lobule. 
 
 In what tissue are they most numerous ? In the glan- 
 dular system. 
 
 What peculiarity have they in the brain and cord ? They 
 are large and surround the blood vessels. 
 
 The vessels on the right side of the head and face empty 
 into what? Into the ductus lymphaticus dexter. 
 
 How long is it ? One inch. 
 
 What is its diameter? One-twelfth to one-eighth inch. 
 
 Where does it empty ? At the j unction of the right sub- 
 clavian with the internal jugular vein. 
 
 Where do the vessels from the inferior extremity empty ? 
 Into the thoracic duct. 
 
 What are lacteals ? Intestinal lymphatics. 
 
 Where do they empty? Into the receptaculum chyli. 
 
 Where do you find it ? Opposite the second lumbar ver- 
 tebra. 
 
 What begins there ? The thoracic duct. 
 
 Into what does the thoracic duct empty? Into the 
 junction of the left internal jugular with the subclavian 
 vein. 
 
 What is the only direct communication between the 
 lymphatics and veins ? Where these two ducts empty. 
 
ABSORPTION. 117 
 
 What prevents the blood from passing into the ducts? 
 The valves. 
 
 Name the coats of lymphatics ? External, middle and 
 internal. 
 
 Which are the same as those of the veins ? External and 
 internal. 
 
 Describe the middle coat? Fibrous and elastic tissue 
 with non-striated muscular fibres. 
 
 Why are lymphatics so easily broken ? On account of 
 their thin walls. 
 
 Where do the valves begin in lymphatics ? Near their 
 origin. 
 
 How are they arranged ? In pairs. 
 
 They are most abundant in what lymphatics? In the 
 superficial. 
 
 What is the distance between the valves ? One-twelfth 
 to one-eighth inch. 
 
 Valves are most numerous in what extremity ? Lower. 
 
 What is their function ? To aid the forward flow. 
 
 Prove that lymphatics are contractile ? They will con- 
 tract if the thoracic duct is irritated. 
 
 Have stomata been demonstrated ? No. 
 
 Why do you think they exist ? The absorption of fats 
 can be accounted for in no other way. 
 
 How many lymphatic glands are there? Six hundred 
 to seven hundred. 
 
 How divided? Superficial and deep set. 
 
 How are the superficial arranged ? At the folds and flex- 
 ures and around the vessels coming from the head. 
 
 Where are the deep ones most numerous ? Around the 
 vessels coming from the glandular system. 
 
 Where do you find the mesenteric glands ? Between the 
 folds of the mesentery. 
 
 What shape are the glands ? Flattened lenticular. 
 
Il8 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What color are they? Grayish white or reddish. 
 
 Consistence of them ? Consistence of liver. 
 
 Where do the blood-vessels enter ? At the hiltim. 
 
 Where do the efferent vessels emerge? At the hilum. 
 
 What is the appearance on the surface ? Tuberculated. 
 
 Why? The follicles project beneath the investing mem- 
 brane. 
 
 How is the gland divided? Cortical and medullary sub- 
 stance. 
 
 What is the color of each ? Cortical is reddish gray and 
 the medullary is white. 
 
 Give the anatomy of the gland ? It is divided into nu- 
 merous little glands by fibrous tissue. 
 
 What are vasa afferentia? Arteries going to the gland. 
 
 How many to each gland? Two to six. 
 
 Describe them ? Pass to the medullary portion and break 
 up into several branches to be distributed to the cortical sub- 
 stance. 
 
 How many vasa eflferentia ? One to three. 
 
 Describe them ? They are formed from capillary loops, 
 which all center into one or three veins. 
 
 How many arteries go to a gland ? Two to six. 
 
 Where do they penetrate ? At the hilum. 
 
 What is the action of the lymphatic glands as regards 
 the rapidity of the circulation ? They slow it. 
 
 What is the function of lymphatic glands? To manu- 
 facture white corpuscles. 
 
 What is the function of lacteals? To absorb fats. 
 
 What else is absorbed by them ? Albuminose, saccharine 
 matters and inorganic salts. 
 
 Proof of absorption taking place by the skin ? Can get 
 physiological effects from medicines given by inunction. 
 
 What is the quickest way to produce salivation ? By 
 inunctions. 
 
ABSORPTION. 119 
 
 What can be absorbed by the respiratory passages ? 
 Gases. 
 
 Give an illustration of absorption taking place from a 
 closed cavity? Effusions into serous cavities are gotten rid 
 of in this way. 
 
 What change does bile undergo if it remains in the gall 
 bladder ? It becomes inspissated. 
 
 How are fats absorbed ? As an emulsion. 
 
 How is mercury absorbed? As such. 
 
 Give the variations of absorption ? Curara. 
 
 How is absorption influenced by haemorrhage? It in- 
 creases absorption. 
 
 How does the rapidity of the circulation influence it? It 
 increases it. 
 
 How does the nervous system influence it ? By influ- 
 encing the blood supply. 
 
 How is it influenced by cutting the cerebro-spinal nerve 
 to the blood-vessels? It lessens absorption. 
 
 How is the exudation in the lungs in pneumonia gotten 
 rid of? By absorption. 
 
 Why do you give digitalis ? To increase the rapidity of 
 the circulation. 
 
 Why is one thirsty after haemorrhage? On account of 
 the blood taking water from the tissues. 
 
 How are effusions gotten rid of? By tapping and by ab- 
 sorption. 
 
 Getting rid of them by absorption is based on what prin- 
 ciple ? An effort of the blood to remain the same. 
 
 What class of medicines are indicated? Diaphoretics, 
 diuretics and hydrogogue cathartics. 
 
120 COMPKND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XXI. 
 
 IMBIBITION. 
 
 Define it ? Ans. Drinking up. 
 
 What will influence it ? The kind of membrane and 
 liquid and the temperature. 
 
 What liquid is imbibed most freely ? Distilled water. 
 
 What is the effect of alcohol and saline solutions ? Re- 
 tards imbibition. 
 
 What membranes imbibe most freely? Homogeneous 
 membranes. 
 
 Illustrate the influence of temperature ? Put a cow-hide 
 in hot water and one in cold, the former gets soft first. 
 
 Describe an endosmometer ? A bell glass over which an 
 animal membrane is stretched is floated on water. 
 
 Define osmosis ? Passing through a membrane. 
 
 Define endosmosis ? That is the strongest current. 
 
 Define exosmosis ? The weaker current. 
 
 What conditions are necessary for osmosis to take place ? 
 There must be two liquids separated by a membrane, the 
 liquids must be mixable and capable of wetting the mem- 
 brane. 
 
 Is it necessary for the liquids to be of different den- 
 sities ? No. 
 
 Illustrate the physiological application of these condi- 
 tions ? The products of digestion and the plasma of the 
 blood both wet the wall of the blood vessels and then pass 
 to the blood. 
 
 What will produce the most powerful endosmotic cur- 
 rent ? Albumin. 
 
 Does it pass through ? It does not. 
 
 What change must it undergo to pass through ? Must 
 be changed to albuminoids. 
 
 
IMBIBITION. 121 
 
 Give an illustration of albumin producing a current and 
 not passing through ? Break the hard shell from an egg and 
 insert this end into water, in the other end insert a glass tube 
 and the water rises in the egg, forcing the egg into the tube. 
 
 Through what kind of a membrane does absorption take 
 place ? Homogeneous. 
 
 What do you mean by homogeneous ? Alike throughout. 
 
 What do you mean by heterogeneous ? Where it is not 
 the same throughout. 
 
 Through what blood vessels does the greater part of 
 absorption take place ? The venous radicals. 
 
 What is hygrometricity ? The power to take on and give 
 off water. 
 
 What is water of composition ? Water necessary to the 
 make up of a part. 
 
 What is interstitial water ? Water in the interstices. 
 
 Where is the water of composition in a homogeneous 
 membrane ? Diffused throughout. 
 
 Give the mechanism of osmosis in the case of two 
 liquids that will diffuse with each other and separated by 
 a membrane? Both wet the membrane, one wetting it more 
 than the other, here they mix and then pass to the side of 
 the weakest current. 
 
 Give the law of dififusibility of liquids. They diffuse 
 with inverse ratio to their densities. 
 
 What effect has chloride of sodium on the diffusion of 
 liquids ? Lessens the diffusibility. 
 
 What effect has high temperature ? Increases it. 
 
 Explain the absorption of a saturated solution of cane 
 sugar in the small intestines? The sugar and serum both 
 wet the membrane and mix, they then pass to the exosmotic 
 side, the blood vessels. 
 
 Why does the tissue near the gall bladder become stained 
 after death ? There is no blood to wash it away. 
 
 Give the variation of absorption. Curare. 
 
122 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XXII. 
 
 LYMPH AND CHYLE. 
 
 What is lymph ? Ans. The contents of lymphatics and 
 of the thoracic duct during the interval of digestion. 
 
 How is it obtained ? From the thoracic duct during the 
 intervals of digestion. 
 
 How much is there ? Four and a half pounds. 
 
 Give the properties of lymph? Transparent, yellowish 
 fluid of a characteristic odor, specific gravity 1022. 
 
 What does it do if it is drawn and allowed to stand ? It 
 clots. 
 
 How does the clot differ from that of blood ? It is softer 
 and no serum separates it. 
 
 Why ? Less fibrin produced. 
 
 Does it ever coagulate in the vessels during life ? 
 Rarely. 
 
 Give the composition of lymph ? Same as blood with the 
 exception of red corpuscles. 
 
 What is the origin of the red corpuscles when you find 
 them ? From the blood. 
 
 Why is a lymph clot smaller than blood clot ? Lymph 
 has less solid matter. 
 
 What are lymph corpuscles ? Same as white blood cor- 
 puscles. 
 
 What is the origin of lymph ? From the blood and the 
 tissues. 
 
 Why think part comes from the tissue ? Because lymph 
 has more urea than blood. 
 
 What is the function of lymph ? To carry excrementi- 
 tious products from the tissue to the blood. 
 
 What is chyle? The contents of the thoracic duct during 
 or just after digestion. 
 
LYMPH AND CHYLK. 1 23 
 
 Give its properties? Milky fluid, saline taste, odor of 
 semen, specific gravity 1024. 
 
 How is it obtained ? Make a fistula into the thoracic duct 
 during digestion. 
 
 Quantity? Varies with the kind and quantity of food. 
 
 How does it differ from lymph in its composition? It 
 has more albumin, fibrin and salts. 
 
 What is the microscopical appearance of chyle ? Has a 
 niilky appearance. 
 
 Has lymph a circulation ? Yes. 
 
 What kind of a flow ? Slow and irregular. 
 
 What is the rapidity of the flow? About an inch per 
 second. 
 
 What is the main cause of lymph circulation ? The force 
 of osmosis and transudation. 
 
 What is transudation ? A passing through. 
 
 What causes assist lymph circulation? Valves, contrac- 
 tion of the heart, expiration and muscular contraction. 
 
 Where are lymphatics contractile? The large ones and 
 those of medium size. 
 
 How does pulsation of the heart assist? By making 
 pressure on the thoracic duct in its passage under the arch 
 of the aorta. 
 
 When does muscular contraction ? When the valves are 
 perfect and the contraction intermittent. 
 
 What influence has inspiration ? Slows it. 
 
 Expiration? Increases its rapidity. 
 
124 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XXIII. 
 
 SECRETION. 
 
 Define it? Ans. Something manufactured in a gland. 
 
 Do they exist as such in the blood ? No. 
 
 Where are they produced ? In the gland. 
 
 When? All the time. 
 
 By what is the active principle produced? By the 
 epithelium. 
 
 How are the secreting cells divided ? Into an outer and 
 inner zone. 
 
 Which is the outer zone ? The one next to the tubular 
 membrane. 
 
 Out of what is the ferment formed ? From the ferment 
 forming substance. 
 
 What produces pepsinogen ? The inner zone of the pep- 
 tic cells. 
 
 What produces pepsin ? It is changed pepsinogen. 
 
 What is zmogen ? Name given to substances which are 
 changed during the digestive ferment. 
 
 What is the relation of the blood supply to the discharge 
 of secretions ? Direct. 
 
 How is the blood supply to a gland at the time of its 
 activity ? It is very much increased. 
 
 Why ? To furnish the wate^ element to wash out the 
 active principle. 
 
 How is it during the interval of activity ? Just enough 
 for nutrition. 
 
 What part is being formed then ? Active principle. 
 
 What influence has the composition of the blood on se- 
 cretion ? None. 
 
 What effect has blood pressure ? The secretion increases 
 with the pressure. 
 
SECRETION. 1 25 
 
 What effect has the nervous system? It influences the 
 blood supply. 
 
 Has the nervous system any other influence ? It has. 
 
 Name it? Mental emotion, pain, etc., cause the flow of 
 tears. 
 
 What condition in a gland is necessary for secretion to 
 take place? Must have epithelium. 
 
 Give the exception ? The mammary gland. 
 
 What do you mean by paralytic secretion? Secretion 
 without blood supply. 
 
 Give the anatomical classification of glands ? Secreting 
 membranes, follicular, tubular racemose and ductless glands. 
 
 What is the simplest form ? The secreting membrane. 
 
 Name one ? Synovial membranes. 
 
 What do you mean by blood glands ? Ductless glands. 
 
 How are secretions classified? Transitory and perma- 
 nent secretions. 
 
 Where do you find true synovial membrane ? At the 
 diarthrodial articulations. 
 
 Give their physiological anatomy ? Fibrous and inelastic 
 tissue lined by epithelium. 
 
 Describe a bursae? A closed sac with semi-fluid con- 
 tents placed between a tendon and bone. 
 
 Function ? To prevent friction. 
 
 What is the arrangement of synovial membranes ? 
 Around the joint. 
 
 Describe the synovial fluid ? Colorless, very viscid alka- 
 line fluid. 
 
 Give its composition ? Water, organic matter, chlorides, 
 phosphates and carbonates. 
 
 Function ? To lubricate the joint. 
 
 Give the anatomical division of mucous membranes ? 
 Those covered with pavement and those covered with 
 columnar epithelium. 
 
126 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Name the membranes covered with pavement epithe- 
 lium ? Mouth, lower part of pharynx, oesophagus, con- 
 junctiva, female urethra and vagina. 
 
 Give their physiological anatomy? Chorion, basement 
 membrane and epithelium. 
 
 Where are the glands situated? In the sub-mucous 
 tissue. 
 
 What kind of glands ? Simple racemose glands. 
 
 Name the membranes covered with columnar epithe- 
 lium ? The alimentary canal below the oesophagus, the. ducts 
 of all glands, Eustachian tube, male urethra and Fallopian 
 tube. 
 
 What is the condition of the cilia during life ? They are 
 in constant motion. 
 
 How are they directed ? Toward the opening. 
 
 Give the physiological anatomy of these membranes ? 
 They have a chorion, basement membrane and epithelium. 
 
 What kind of glands find in these ? Follicular. 
 
 What mucous membranes can not be classed with these 
 two varieties ? Urinary bladder, pelvis of the kidney and 
 uterus. 
 
 Why ? They have mixed epithelium. 
 
 By what is the mucus produced ? Mucous glands. 
 
 Give the properties of mucus ? Thick, grayish fluid of 
 alkaline reaction. 
 
 Where is it not alkaline in reaction? In the vagina. 
 
 Why is this acid ? To prevent coagulation of the men- 
 strual flow. 
 
 What is the action of water on mucus? It swells it. 
 
 Exception? The mucus of the conjunctiva is coagulated 
 by water. 
 
 Give the composition of mucus? Mucin, water and 
 inorganic salts. 
 
 Function of mucus ? To lubricate and protect. 
 
SECRETION. 127 
 
 Where do you find the sebaceous glands ? All parts of 
 the skin where there is hair. 
 
 Where are they absent ? Palms of the hands and soles 
 of the feet. 
 
 What is their relation to the hairs ? They are in close 
 relation and they open into the follicle. 
 
 How are they divided ? Into large and small variety. 
 
 Where do you find the small ones ? In relation with the 
 large hairs. 
 
 Where find the large ones ? In relation with the small 
 hairs. 
 
 What kind of glands are they? Compound or simple 
 racemose. 
 
 How many empty into a large hair follicle ? Four to 
 eight. 
 
 Where are the largest glands found? Nose, eye, ear, 
 penis and areola of the nipple. 
 
 Where do you find the glands of Tyson ? They are the 
 sebaceous glands of the glans penis. 
 
 Give their physiological anatomy ? Same as other com- 
 pound racemose glands. 
 
 Where do you find the ceruminous glands ? In the car- 
 tilaginous part of the ear. 
 
 Describe them ? A tube which terminates in a coil. 
 
 Where do you find the Meibomian glands ? In the tarsal 
 cartilages. 
 
 Describe them ? Made up of a straight duct into which a 
 number of compound racemose glands open. 
 
 Give the composition of sebaceous matter? Albumin, 
 fats, chlorides, phosphates. 
 
 What is smegma ? Sebaceous matter of the glans penis 
 in the male and labia minora in female. 
 
 What is vernix caseosa ? Sebaceous matter covering the 
 foetus at birth. 
 
128 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What is the function of it? To protect the foetus. . 
 
 What is the function of sebaceous matter ? To lubricate 
 the hair and to protect. 
 
 What is cerumen ? Secretion of the ceruminous glands. 
 
 What is its function ? To keep foreign bodies out of the 
 ear. 
 
 On what does its color depend? On the time it has been 
 exposed to the air. 
 
 What is the function of meobomian secretion ? To pre- 
 vent an overflow of tears. 
 
 CHAPTER XXIV. 
 
 MAMMARY GLANDS. 
 
 What is their shape in the female ? Ans. Hemispher- 
 ical. 
 
 Where are they situated ? Anterior part of the thorax 
 over the pectoral muscles. 
 
 From what point do they extend vertically ? Second to 
 the seventh rib. 
 
 What is their extent laterally ? From axilla to sternum. 
 
 How are they before puberty? Undeveloped. 
 
 How are they during pregnancy ? They become enlarged. 
 
 What effect has old age ? They atrophy. 
 
 Which gland is the largest ? The left one. 
 
 What separates them from the pectoral muscles ? Deep 
 fascia. 
 
 What is the shape of the outer surface ? Convex. 
 
 What is the maurilla ? The nipple. 
 
 Give their anatomy ? Ducts, muscular and connective 
 tissue and blood vessels. 
 
MAMMARY GLANDS. 129 
 
 What is the arrangement of the muscular fibres ? They 
 run in no definite direction. 
 
 What is the color of the surface ? Brown. 
 
 By what is it surrounded ? By the areola. 
 
 What color is the areola in a virgin? Pink. 
 
 What influence has pregnancy ? It darkens it. 
 
 What is the color after lactation? Dark brown. 
 
 What is the function of the muscular fibres ? To com- 
 press the milk ducts. 
 
 What is the shape of the nipple ? Conical. 
 
 What effect has mechanical excitement ? Makes it erect. 
 
 Why? It causes the muscular fibres to contract. 
 
 What do you find on the surface of the nipple? Pa- 
 pillae. 
 
 What is the cause of the tuberculated appearance of the 
 areola ? It is caused by the large sebaceous glands found 
 beneath it. 
 
 On what does the areola rest? On the subjacent gland- 
 ular structure. 
 
 What is the function of these glands? To moisten. 
 
 To what class of glands do the mammary glands belong ? 
 Compound racemose. 
 
 Of what are they made up ? I^obes. 
 
 How many lobes ? Fifteen to twenty-four. 
 
 How are the lobes divided ? Into lobules. 
 
 Of what does the smallest lobule consist ? Secreting ves- 
 icles. 
 
 How many excretory ducts are there ? Ten to fourteen. 
 
 What are they called ? Lactiferous or galactophorous 
 ducts. 
 
 Where are they dilated ? Beneath the areola. 
 
 What is it called? Galactophorous sinuses. 
 
 What is the function of these dilatations ? They are re- 
 ceptacles for the milk. 
 9 
 
130 COMPEND OF HUMAN PHYSIOLOGY. 
 
 How much do they hold? About two fluid ounces. 
 
 Name the coats of the ducts? External, middle and in- 
 ternal. 
 
 Describe the external? Fibrous tissue with some elastic 
 fibres. 
 
 Describe the middle ? Non-striated muscular fibres ar- 
 ranged longitudinally. 
 
 What is the function of this coat? To shorten the 
 duct. 
 
 Describe the internal ? It is simply an amorphous mem- 
 brane. 
 
 Of what is each acinus made up ? Twenty to forty secret- 
 ing vesicles. 
 
 What lines these vesicles ? Epithelium. 
 
 When? During the interval of lactation. 
 
 What kind of epithelium? Polygonal cells. 
 
 What becomes of it during lactation? It is exfoliated. 
 
 What is the condition of the ducts during the interval of 
 lactation? They become retracted. 
 
 Where are the important and characteristic constituents 
 of milk formed ? In the gland. 
 
 What is the origin of the inorganic principles? They 
 are separated from the blood. 
 
 Name the constituents produced in the gland? Sugar, 
 fat, and casein. 
 
 Is milk a secretion or excretion? Secretion. 
 
 When is milk produced? All the time. 
 
 Does the quantity of food influence the quality or quan- 
 tity of milk ? It does not. 
 
 What effect have liquids ? It increases the amount. 
 
 Alcohol? Increases it. 
 
 Mental emotion? lessens it, or it may stop it. 
 
 How much milk is produced in a day ? Two to three 
 pints. 
 
MAMMARY GLANDS. I 3 T 
 
 How much can be drawn from a full breast? Two fluid 
 ounces. 
 
 What effect has the menstrual period on the amount of 
 milk ? It diminishes it. 
 
 Pregnancy? It also diminishes it. 
 
 Give the properties of milk ? White, opaque, sweet fluid, 
 alkaline in reaction, specific gravity 1032. 
 
 What do you mean by coagulation ? Separation into 
 whey and curd. 
 
 What effect has a thunder storm on milk? It coagu- 
 lates it. 
 
 If milk stands how does it separate ? Into milk and 
 cream. 
 
 How much cream should there be in healthy milk? One- 
 fifth to one-third. 
 
 Give the composition of cream? Almost entirely milk 
 globules. 
 
 What is the specific gravity of cream? 1024. 
 
 What is the microscopical appearance of milk? Minute 
 globules held in suspension in a clear fluid. 
 
 What are the globules called ? Milk globules. 
 
 Give the composition of milk? Water, casein, albumin 
 and inorganic salts. 
 
 How much water ? Nine hundred parts. 
 
 What is the name for the nitrogenized constituent? Casein. 
 
 Where is it produced? In the gland. 
 
 From what ? Principles derived from the blood. 
 
 In what form is it in milk? In solution. 
 
 How is it when first drawn ? In solution. 
 
 How does the milk of a cow differ from mother's milk ? 
 Mother's milk is poorer in casein and richer in butter and 
 sugar. 
 
 What is the object of feeding a child on cow's milk? To 
 make it as near as possible like the mother's milk. 
 
132 COMPEND OF HUMAN PHYSIOLOGY. 
 
 How make cow's milk like a woman's ? Take the cream 
 and add water and sugar. 
 
 On what does the coagulation of milk depend? On the 
 formation of lactic acid. 
 
 How is lactic acid formed ? By the decomposition of 
 sugar of milk. 
 
 "What holds the fats in milk in emulsion ? The liquid 
 casein and water. 
 
 What is the other name for the fats ? Butter. 
 
 How does butter from a woman's milk differ from that 
 of a cow ? It is softer. 
 
 Give the composition of butter? Olein, palmitin, cap- 
 riline, etc. 
 
 What is lactose ? Sugar of milk. 
 
 Give the peculiarities of milk sugar? It is readily 
 changed to lactic acid, but takes on alcoholic fermentation 
 slowly. 
 
 What is the function of the alkaline carbonates? To 
 preserve the fluidity of the casein. 
 
 In a general way what does milk contain ? All the ele- 
 ments necessary for nutrition. 
 
 Are there any variations in its composition? Yes. 
 
 Name them ? Milk during lactation and pregnancy and 
 colostrum. 
 
 How is the child affected by the milk when menstruation 
 begins? It becomes emaciated. 
 
 How, by pregnancy? It becomes emaciated. 
 
 Why? Milk then has little nutritious properties. 
 
 What is colostrum ? The secretion of the mammary 
 glands just after parturition. 
 
 Give its composition ? It has more sugar and inorganic 
 salts than milk. 
 
 Its function? To relieve the infant of the accummulated 
 meconium. 
 
EXCRETION. 133 
 
 What causes it to act as a laxative ? The sugar and in- 
 organic salts. 
 
 What is meconium? The first faecal matter of the child. 
 
 How long does milk preserve the characters of colostrum ? 
 Eight to ten days. 
 
 Give the composition of the milk of an infant ? Eess 
 butter and more susrar than woman's milk. 
 
 CHAPTER XXV 
 
 EXCRETION. 
 
 Define it ? Ans. Something thrown off from the body. 
 
 What fluids carry it from the tissue? Blood and lymph. 
 
 Where is it carried? To the organs of excretion. 
 
 What becomes of them ? They are thrown off. 
 
 Do they in any way aid in digestion? Only by getting 
 rid of the waste products. 
 
 Are they produced in glands ? No. 
 
 What trouble if they are not thrown off? The system 
 becomes poisoned. 
 
 How are they discharged? Continuously. 
 
 Why? To prevent poisoning of the system. 
 
 What excrementitious product does nervous tissue pro- 
 duce when it wears out ? Cholesterin. 
 
 Where is it gotten rid of? By the liver. 
 
 What does the wear of muscular tissue produce ? Urea. 
 
 How eliminated ? By the kidney and skin. 
 
134 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XXVI. 
 
 SKIN. 
 
 Name the function of the skin? Ans. To preser\*e the 
 form of the muscles, and it acts as an organ of excretion and 
 sensation and as a protectile covering. 
 
 What is the extent of the skin ? Sixteen square feet. 
 
 Where is it thickest? Where it is most exposed. 
 
 What is the thickness of the skin? One-half to one- 
 eighth inch. 
 
 Where is it thinnest? Glans penis, lips and external ear. 
 
 How is the skin naturally divided ? Into two layers. 
 
 Names? Epidermis, or false skin, and dermis, or true. 
 
 What is the panniculus adiposus ? The layer of fat be- 
 neath the skin. 
 
 Where is it absent? Outer ear, eyelids and penis. 
 
 Where is it thickest? On the abdomen. 
 
 What is the condition of the under surface of the skin ? 
 It is rough. 
 
 How is the true skin divided ? Into a reticulated and 
 papillary layer. 
 
 Give the anatomy of the reticulated layer ? Elastic and 
 fibrous tissue with some non-striated muscular fibres. 
 
 Where are the muscular fibres most abundant ? Around 
 the sebaceous glands and hair follicles. 
 
 Explain "goose flesh"? It is caused by a projection of 
 the follicles above the skin. 
 
 Where is the contraction most marked? Nipple, penis 
 and scrotum. 
 
 Describe the papillary layer ? A simple amorphous mem- 
 brane. 
 
 How are the papillae formed? By eversions of this 
 layer. 
 
SKIN. 135 
 
 How are they divided ? Into simple and compound 
 papillae. 
 
 Where are they largest ? Nipple, palms of the hands and 
 soles of the feet. 
 
 How do the blood vessels terminate in the papillae ? 
 They form a flexns. 
 
 What is the epidermis? The false or scarf skin. 
 
 What kind of tissue is it ? Extra vascular tissue. 
 
 Name the layers that make it up ? Malpighian and horny 
 layer. 
 
 Give the composition of the Malpighian layer ? A single 
 layer of primordial cells with coloring matter. 
 
 On what does the color depend ? On the amount and tint 
 of the pigmentary matter in the Malpighian layer. 
 
 What is the thickness of this layer? One seven-thou- 
 sandth to one seventy-fifth inch. 
 
 Describe the horny layer ? Several strata of hard flat- 
 tened cells. 
 
 What is the function of the epidermis ? It gives protec- 
 tion. 
 
 Where is it thickest ? Palms of the hands and soles of 
 the feet. 
 
 What becomes of the epidermis when it wears out ? It 
 is thrown off. 
 
 Name the appendages of the skin? Nails and hair. 
 
 How is a nail divided ? Into root, body and free extremity. 
 
 Describe the root? Its edge is thin and ragged, and this 
 part is softer than the rest of the nail. 
 
 How long is the root ? One-fourth to one-third the entire 
 length. 
 
 Describe the body? Thick and is marked by longitudinal 
 lines; it extends from root to free extremity. 
 
 What is the lunula ? The semilunar white mark on the 
 body near the root. 
 
136 COMPEXD OF HUMAN PHYSIOLOGY. 
 
 What causes it ? This part is less vascular. 
 
 What is the matrix ? The part of the skin on which the 
 nail rest. 
 
 What is the free border? That extends beyond the ma- 
 trix. 
 
 How long may it become ? Two inches. 
 
 Where is the nail thickest? Central portion. 
 
 How many layers has a nail ? Two. 
 
 How does the nail grow? The horn}- layer grows from 
 the bed and from the root. 
 
 What are the functions of the nail? Organs of prehen- 
 sion and protection. 
 
 On what parts of the body are hairs not found ? Soles 
 of the feet, palms of the hands, outer ear, penis, labia mi- 
 nora, etc. 
 
 How are hairs divided? Long, short and down)' hairs. 
 
 Where are the long hairs found ? Head, axilla, and 
 around the genitals. 
 
 Where do you find the short hairs? Around the open- 
 ings. 
 
 Where are the downy hairs found? Over the general 
 surface. 
 
 How are hairs set in the skin? Obliomely. 
 
 How long do long hairs become ? Two or three feet. 
 
 How long are the short? One-fourth to one-half inch. 
 
 How do hairs terminate that have never been cut ? In a 
 pointed extremity. 
 
 Is hair coarser in male or female ? Female. 
 
 Is it coarser in blondes or brunettes ? In the brunettes. 
 
 Give the properties of hair ? Elastic, hygrometric, and 
 it becomes electric on friction. 
 
 What is the root of the hair? That part imbedded in the 
 skin. 
 
 How deep do the roots penetrate ? The downy go only to 
 the true skin and the large' go through it. 
 
 
PERSPIRATION. 137 
 
 Describe the root ? Soft, large and terminates in a bulb. 
 
 What surrounds the root? The sheath. 
 
 What surrounds the sheath? The hair follicle. 
 
 What forms the sheath? The horny layer of the skin. 
 
 What forms the follicle ? The malpighian layer. 
 
 Give the structure of hair ? They are fibrous tissue and 
 it is covered by small cells. 
 
 How is the hair nourished ? By imbibition. 
 
 On what does the color of hair depend? On the pigment- 
 ary matter. 
 
 What is the cause of sudden bleaching? The medulla 
 fills with air. 
 
 What is the cause of blanching in old age ? The loss of 
 pigmentary matter. 
 
 CHAPTER XXVII. 
 
 PERSPIRATION. 
 
 Define it ? Ans. The action of the skin as an excretory 
 organ. 
 
 Is the skin an organ of excretion or secretion ? Excre- 
 tion. 
 
 Name the products excreted by the skin? Urea, car- 
 bonic acid, water and organic matter. 
 
 What would be the result of covering the skin with some 
 impermeable substance ? Would result in death. 
 
 What would be the cause of death ? It would suppress 
 the action of the skin and depress the temperature. 
 
 What glands in the skin are most numerous ? Sudorip- 
 arous glands. 
 
 Where do you not find them ? Concha of the ear, penis, 
 prepuce, and external ear. 
 
I38 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Where are the orifices of the ducts in the palms of the 
 hands and soles of the feet ? Between the papillary ridges. 
 
 How do the tubes open on the surface ? Obliquely. 
 
 Describe a sudoriparous gland ? A simple tube terminat- 
 ing in a coil. 
 
 What is the size of the coil ? One one-hundred and 
 twenty-fifth to one twenty-fifth of an inch. 
 
 Where are they smallest? Eyelids, ear, nose, penis and 
 scrotum. 
 
 Where are they largest? Areola of the nipple and the 
 perineum. 
 
 How many convolutions in the coiled portion ? Six to 
 twelve. 
 
 Describe the blood-vessels around the coil ? They form a 
 plexus around it and send branches between the convolutions. 
 
 What is the excretory duct ? A continuation of the coil. 
 
 How does it pass through the true skin ? In a straight 
 course. 
 
 How through the false skin ? Spiral course. 
 
 Where is the excretory duct largest? Near the opening. 
 
 What is the peculiarity of the glands of the axilla? 
 They are large and excrete sweat of a peculiar odor. 
 
 How many sweat glands are there? 2,381,000. 
 
 How long is each coil? One-sixteenth inch. 
 
 How long are they all together ? Two and one-third miles. 
 
 Is the action of the skin continuous or intermittent? 
 Continuous. 
 
 How is sweat exhaled from the skin ? In the form of vapor. 
 
 What part of the gland performs the function of excre- 
 tion? The epithelium of the coil. 
 
 How is perspiration excreted ? Continuously. 
 
 What influence has the nervous system on the produc- 
 tion of sweat ? It influences it by influencing the blood sup- 
 ply to the glands. 
 
PERSPIRATION. 139 
 
 Where is the sweat center located? In the lower part of 
 the cervical or dorsal regions. 
 
 What effect would cutting of the sympathetic nerve 
 going to the blood-vessels of the skin have ? It would in- 
 crease the amount of sweat. 
 
 What is the amount of cutaneous exhalation? About 
 two pounds per day. 
 
 What time of the year is it greatest? Summer. 
 
 What varies least in sweat? Urea. 
 
 Give the properties of sweat? Colorless limpid liquid, of 
 acid reaction and characteristic odor. 
 
 Why does sweat become alkaline ? The volatile fatty 
 acids escape. 
 
 What is the specific gravity of sweat? 1003 to 1004. 
 
 Give its composition? Water, urea, fatty matter, chlo- 
 rides, phosphates and sulphates. 
 
 What is the most important part of sweat ? Urea. 
 
 What kind of acids are excreted? Fatty acids. 
 
 Name some of them ? Formic, butyric, cupric and acetic 
 acids. 
 
 What parts produce sweat with peculiarities? Axilla, 
 between the toes and around the genitals. 
 
 Describe the sweat produced by them ? It is alkaline in 
 reaction, has a strong odor and stains yellow. 
 
 What is the cause of its odor ? It is caused by the secre- 
 tions from other follicles in these parts. 
 
140 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XXVIII. 
 
 KIDNEYS. 
 
 What was the old idea of the formation of urea ? Ans. 
 That it was formed in the kidneys. 
 
 Give the reasons why they thought so? (1) When the 
 kidneys were removed there was no uremia for several days. 
 (2) When urea was injected into the veins there was no ure- 
 mia. (3) When the ureters were tied there would be uremia. 
 
 Where is urea produced ? In the tissue. 
 
 It represents the wear of what tissue ? Muscular tissue. 
 
 Why is there not an increased quantity of urea in the 
 blood the first few days after removal of the kidneys ? It 
 is eliminated vicariously. 
 
 What organs normally eliminate urea? Skin and kidney. 
 
 Which eliminate it vicariously? Lungs and alimentary 
 canal. 
 
 What change does urea undergo in contact with a mu- 
 cous surface ? Changes to carbonate of ammonia. 
 
 What symptom would it produce in the bowel ? Diarrhoea. 
 
 What in the stomach ? Vomiting. 
 
 In the lungs? Coughing. 
 
 Why does it produce these symptoms ? It acts as an irri- 
 tant. 
 
 When urea is injected into the blood, why will there 
 be no uremia ? It acts as a diuretic, which increases the 
 amount eliminated by the kidneys. 
 
 Why will tying of the ureters increase the quantity of 
 urea in the blood, while cutting the kidneys out will not 
 for several days? In tying the ureters the pain prevents 
 the vicarious elimination of urea. 
 
 What takes the urea from the tissues ? The blood and 
 lymph. 
 
KIDNEYS. 141 
 
 Where is it carried ? To the skin and kidneys. 
 
 What is the color of the blood in the renal vein? Bright 
 red. 
 
 Why ? Has a large amount of oxygen. 
 
 What is the purest blood in the body ? That of the renal 
 vein. 
 
 Why? It has no urea and has much oxygen. 
 
 Is urea an excretion or secretion? Excretion. 
 
 What part of the kidney separates it from the blood? 
 The epithelium in the contorted tube. 
 
 In Bright's disease what becomes of the epithelium ? It 
 is exfoliated. 
 
 Is it reproduced ? It is not. 
 
 How is the urea eliminated when the epithelium is de- 
 stroyed? Vicariously. 
 
 Where is the watery part of the urine separated from 
 the blood ? In the Malpighian corpuscle. 
 
 What is the effect of extirpating one kidney ? It makes 
 the other one act continuously. 
 
 What is the effect of extirpating a kidney on the appe- 
 tite ? It increases it. 
 
 What influence has the blood pressure on the quantity 
 of urine ? The higher the pressure the greater is the amount 
 of urine. 
 
 Why will digitalis act as a diuretic? It increases the 
 blood pressure. 
 
 Effect of cutting the nerve going to the kidney? It in- 
 creases the flow of urine. 
 
 Effect of injuring the pneumogastric nerve near the ori- 
 gin on the quantity of urine? Increases it. 
 
 Effect of injuring the floor of the fourth ventricle ? 
 Would cause diabetes mellitis. 
 
 What effect has digestion on the amount of urine ? It in- 
 creases it. 
 
I42 COMPEND OF HUMAN PHYSIOLOGY. 
 
 When is urine formed? All the time. 
 
 Why ? To get rid of urea. 
 
 Do both kidneys act at once ? The)- do not. 
 
 What change is there in the composition of the blood in 
 passing through the kidney ? It loses urea and water. 
 
 What is the upper expansion of the ureters called ? The 
 pelvis of the kidney. 
 
 What is the calyx ? A process of the pelvis. 
 
 What do the calyces receive ? The apices of the pyramids. 
 
 What is the diameter of the ureters ? About same as 
 that of a goose quill. 
 
 How long are they ? Fifteen to eighteen inches. 
 
 What is their extent ? From kidney to bladder. 
 
 How many coats have they ? Three. 
 
 Describe the external coat? Fibrous tissue with some 
 elastic fibres. 
 
 Describe the middle coat? Non-striated muscular fibres 
 arranged in no definite direction. 
 
 Describe the internal coat? It is a thin, smooth, mucous 
 membrane. 
 
 Where are the ureters constricted ? Near the bladder. 
 
 How do they penetrate the bladder ? Obliquely. 
 
 What is the object of this? To prevent regurgitation of 
 urine. 
 
 What is the function of the bladder ? Acts as a reservoir 
 for the urine. 
 
 Where do the ureters empty ? At the base of the trigo- 
 niim. 
 
 Where do you find it ? At the base of the bladder. 
 
 What is the shape of the bladder ? Triangular. 
 
 What shape is it when distended ? Globular. 
 
 Where do you find the bladder? In the pelvic cavity. 
 
 How much will the bladder hold ? Normally from one to 
 two pints. 
 
KIDNEYS. 143 
 
 Is it largest in male or female ? Female. 
 
 How is the bladder held in place ? By ligaments. 
 
 Name the coats of the bladder? External, middle and 
 internal. 
 
 Describe the external coat ? It is peritoneal and is com- 
 plete only behind. 
 
 How many layers in the middle coat ? Three. 
 
 Describe the internal ? Longitudinal mucular fibres run- 
 ning antero-posteriorly. 
 
 Describe the middle layer of this coat ? Circular fibres, 
 arranged in bands on the anterior surface. 
 
 Describe the internal layer ? Pale fibres arranged longi- 
 tudinally. 
 
 With what are they continuous? With the muscular 
 fibres of the ureters, urachus and urethra. 
 
 Describe the sphincter vesicae ? A collection of circular 
 fibres a half inch wide, found at the neck of the bladder. 
 
 What is its function? To prevent a flow of urine and 
 also to keep the semen out of the bladder. 
 
 Describe the mucous membrane of the bladder ? Smooth, 
 pale, thick and loosely attached to the sub-mucous tissue, ex- 
 cept at the corpus trigonum. 
 
 What is the shape of the trigonum ? Triangular. 
 
 What is its composition ? Fibrous tissue with some mus- 
 cular fibres and elastic tissue. 
 
 What is the uvula vesicae ? A fold of the mucous mem- 
 brane at the urethral opening. 
 
 What part of the mucous membrane are the blood-ves- 
 sels most numerous ? At the fundus. 
 
 What is the cause of the discharge of urine into the 
 pelvis of the kidney ? The pressure brought about b}' sep- 
 aration of the urine from the blood. 
 
 What causes it to flow through the ureter ? Force from 
 behind and contraction of the ureters. 
 
144 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What causes the desire to void urine ? Pressure on the 
 sensory nerves of the bladder. 
 
 How frequent is it? Three to five times per da}'. 
 
 Give the mechanism of the discharge from the bladder ? 
 The sphincter dilates and the urine is forced out by contrac- 
 tion of the bladder and abdominal muscles. 
 
 Is it voluntary ? It is so at first. 
 
 Where is the center located that is supposed to control 
 the bladder ? Opposite the fourth lumbar vertebra. 
 
 Give the properties of urine ? Clear amber-colored non- 
 viscid fluid with aromatic odor, acid reaction, and specific 
 gravity 1020. 
 
 How much urine is passed in a day ? About fifty-two 
 ounces. 
 
 What is the cause of the acidity of urine ? Due to the 
 acid phosphate of soda. 
 
 Give the composition of urine ? Water, urea, creatin 
 and creatinin carbonates, phosphates, chlorides and sul- 
 phates. 
 
 Which is the most important constituent? Urea. 
 
 Give its source ? From the oxidation of the tissue. 
 
 Can it be produced in the laboratory ? Yes. 
 
 How ? By the action of sulphate of ammonia on cyanate 
 of potash. 
 
 Into what is it converted when it comes in contact with 
 a mucous surface? Carbonate of ammonia. 
 
 What is the chemical difference between urea and car- 
 bonate of ammonia ? The ammonia has four more atoms of 
 water. 
 
 Where is urea normally found? Urine, blood, lymph, 
 chyle and sweat. 
 
 How can urea be made from carbonate of ammonia ? 
 Heat it to drive off the water. 
 
 In what form is urea in the urine ? In solution. 
 
KIDNEYS. 145 
 
 What effect has watery diet on urea ? It increases the 
 amount excreted. 
 
 Effect of watery diet on specific gravity ? It lowers it. 
 
 What effect has nitrogenized diet? Increases the amount 
 of urea. 
 
 What effect has non-nitrogenized diet ? It lessens it. 
 
 Effect of muscular activity ? Increases it. 
 
 How much urea is eliminated daily? 355 to 460 grains. 
 
 Does uric acid exist in a free state in urine ? No. 
 
 What is its solubility in hot water ? 1800 parts. 
 
 In cold water ? 14000 to 15000 parts. 
 
 In what form is uric acid found ? In the form of urates. 
 
 Which urate is most important ? Urate of soda. 
 
 What is the origin of uric acid ? From the oxidation of 
 tissue. 
 
 How much is excreted in a day ? Six to ten grains. 
 
 In what urine do you find hippuric acid ? In the urine 
 of herbivora. 
 
 Is it a normal constituent of human urine ? It is not. 
 
 How much is eliminated per day ? Seven and one-half 
 grains. 
 
 What is its solubility ? Six hundred parts of cold water, 
 more soluble in dilute hydrochloric acid. 
 
 What is the source of the lactates ? Formed by the ac- 
 tion of lactic acid on the bases. 
 
 What is the source of lactic acid ? From the transforma- 
 tion of glucose. 
 
 What is the source of creatin and creatinin ? Waste of 
 tissue. 
 
 Higher oxidation of them produces what ? Urea. 
 
 How much creatin and creatinin eliminated in a day? 
 Eleven and one-half grains. 
 
 Does oxalate of lime exist in normal urine ? None con- 
 stantly. 
 10 
 
146 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What is oxalyuria? An excess of oxalates ill the urine. 
 
 What is the origin of the inorganic salts in the urine ? 
 Come from the tissues. 
 
 What is the proportion of chloride of sodium in the 
 blood ? Three to four parts per thousand. 
 
 In the urine ? Three to eight parts. 
 
 On what does the amount in the urine depend ? On the 
 amount taken in. 
 
 What is the relation of febrile troubles on the amount 
 of chloride of sodium in the urine ? They lessen tne 
 amount. 
 
 How much is eliminated daily? One hundred and fifty- 
 four grains. 
 
 What is the proportion of sulphates in the urine ? Three 
 to seYen parts per thousand. 
 
 What is their origin ? From within and without. 
 
 What was the old significance of phosphates in the 
 urine? That it was due to brain activity. 
 
 Why? Because nervous tissue is made up largely of phos- 
 phates. 
 
 What is the origin of the phosphates? From without. 
 
 Name the different kinds? Neutral, basic and acid phos- 
 phates. 
 
 Which is the most important one? Acid phosphate of 
 sodium. 
 
 What is the coloring matter of the urine ? Urochrome. 
 
 What is its origin? It is probably formed from haemo- 
 globin. 
 
 Name the gases in the urine? Oxygen, nitrogen, and 
 carbonic acid gas. 
 
 What becomes of the hydrogen introduced with the 
 food ? It goes to form water. 
 
 Proof of water being formed in the body ? There is 
 more discharged than taken in. 
 
KIDNEYS. 147 
 
 At what period of life is the most urine discharged in 
 proportion to the size of the body? Infancy. 
 
 When is the most urea discharged ? Infancy. 
 
 Is there more urine discharged in male or female ? Male. 
 
 What time of the year is most urine discharged ? Winter. 
 
 Why is there less in summer ? It is mostly eliminated 
 by the skin. 
 
 When is the specific gravity of the urine highest ? In 
 the morning. 
 
 Why ? Because it has not been voided during the night. 
 
 What is the color of urine passed in the forenoon ? Light. 
 
 How is the specific gravity ? Low. 
 
 What influence has nitrogenized diet on urine ? It in- 
 creases the amount of urea and increases its specific gravity. 
 
 Effect of liquid food and alcoholic drinks ? Lowers its 
 specific gravity. 
 
 Effect of coffee and tea ? Lowers it and lessens the urea. 
 
 What effect has muscular exercise on the amount of 
 urea ? Increases it. 
 
 Why ? It causes more waste of tissue. 
 
 Effect of mental exercise ? Increases it. 
 
 Why ? It causes waste of tissue. 
 
I48 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XXIX. 
 
 EIVER. 
 
 What part of the liver performs the office of secretion 
 and excretion? Ans. The hepatic cells. 
 
 State the functions of the liver? Secretion, excretion, 
 and the function of a ductless gland. 
 
 What part is an excretion ? Cholesterin. 
 
 What part is a secretion ? Biliary salts and coloring 
 matter. 
 
 What is the office of a ductless gland ? To manufacture 
 something and discharge it into the blood. 
 
 What was formerly thought to manufacture the bile? 
 The racemose glands opening into the biliary duct. 
 
 What is the function of these racemose glands ? To pro- 
 duce mucus. 
 
 Is bile secreted from arterial or venous blood ? Mostly 
 from venous. 
 
 What are the branches of the hepatic artery in the liver ? 
 Vaginal and interlobular. 
 
 What are the branches of the hepatic vein ? Intralobu- 
 lar and sub-lobular. 
 
 Of the portal vein? Vaginal, interlobular and lobular. 
 
 How does the blood get from the liver to the inferior 
 vena cava? Through the hepatic vein. 
 
 Prove that bile can be secreted from arterial blood? Tie 
 the portal vein and will still have bile produced. 
 
 How much bile is secreted in a day? Two to four 
 pounds. 
 
 When is bile discharged into the duodenum ? All the 
 time. 
 
 When is the greatest quantity discharged ? During 
 digestion. 
 
LIVER. 149 
 
 Why is it necessary for bile to be discharged all the 
 time ? To get rid of cholesterin. 
 
 Give the functions of bile ? Nature's purge and disin- 
 fectant, and to aid in digestion. 
 
 What kind of food does it help digest ? Fats. 
 
 Is bile essential to life ? It is. 
 
 Proof? Make a biliary fistula and will result in death. 
 
 Give the properties of bile ? Thick, golden green opaque 
 fluid of a bitter taste and specific gravity 1020 to 1026. 
 
 Composition? Water, biliary salts, cholesterin, inorganic 
 salts and coloring matter. 
 
 What is the origin of the inorganic salts? From with- 
 out. 
 
 What is their function ? They seem to be of little use. 
 
 What is lecithene ? A neutral fatty substance found in 
 bile. 
 
 Where is it found ? Blood, bile, nervous tissue, and yolk 
 of egg. 
 
 What is meant by the recrementitious function of bile ? 
 Its function in digestion. 
 
 What part of it has to do with this function ? The bili- 
 ary salts. 
 
 Name the biliary salts ? Taurocholate and glycocholate 
 of soda. 
 
 How are they formed ? By the action of taurocholic and 
 glycocholic acid on soda. 
 
 Which is found in greatest abundance ? Taurocholate. 
 
 What is the difference between the two? Sulphate of 
 aluminum and iron precipitates taurocholate and not the 
 other. 
 
 Are they proximate principles of bile ? No. 
 
 What is their origin ? They are formed in the liver. 
 
 Name the excrementitious principles of bile ? Choles- 
 terin. 
 
150 COMPEND OF HUMAN PHYSIOLOGY. 
 
 How is it held in solution in the blood ? By the fatty 
 acids. 
 
 How is it held in solution in the bile ? By the biliary salts. 
 
 What are biliary calculi? A collection of crystals of 
 cholesterin. 
 
 In what form is cholesterin usually found ? In solution. 
 
 Name the coloring matter of bile? Bilirubin. 
 
 What is its origin ? It is formed in the liver, probably 
 from haemoglobin. 
 
 Give the test for it ? With nitroso nitric acid it gives a 
 play of colors. 
 
 Give the test for the biliary salts ? Gives a purple with 
 cane sugar and sulphuric acid. 
 
 What is the excrementitious function of the liver ? To 
 excrete cholesterin. 
 
 What is cholesterin? A product of waste of nervous 
 tissue. 
 
 Proof? There is more in the blood coming from nervous 
 tissue. 
 
 Is there any formed in the lower extremity ? There is. 
 
 Proof of its elimination by the liver ? If the function of 
 the liver is stopped the system becomes poisoned with cho- 
 lesterin. 
 
 What is stercorine ? Modified cholesterin. 
 
 When is it discharged as cholesterin? During the in- 
 tervals of digestions. 
 
 What office of the liver resembles that of a ductless 
 gland ? The glycogenic action. 
 
 What does the liver constantly contain ? Glycogen. 
 
 What becomes of the glycogen ? It is converted into 
 glucose. 
 
 What is the composition of glycogen? Carbon, hydrogen 
 and oxygen. 
 
 It belongs to what class? Carbo hydrates. 
 
 j 
 
LIVER. 151 
 
 Give the test for glycogen? With iodine it gives a deep red. 
 
 What does it resemble? Starch. 
 
 How does it exist in the liver cells? In amorphous 
 granules. 
 
 How can you extract it from a decoction ? By precipi- 
 tating it with alcohol. 
 
 Where do you find it in foetal life ? Through all the tissue. 
 
 What is the effect of digestion on glycogen ? It increases 
 the amount. 
 
 What kind of diet will diminish it? Albuminous and 
 fatty diet. 
 
 What will increase it ? Carbo hydrates. 
 
 What change does sugar undergo in the liver? It is 
 changed to glucose. 
 
 What is the source of glycogen in herbivora and in man? 
 From the starch in the vegetable food. 
 
 Give evidence of the glycogenic function of the liver? 
 Sugar is found coming from but not going to the liver. 
 
 When is sugar found in the portal vein ? When an ex- 
 cess is taken in. 
 
 When in the hepatic artery ? When an excess is taken in. 
 
 Give a test for sugar ? Boil with caustic potash and it gets 
 yellow or brown, as to the amount of sugar. 
 
 What kind of blood goes from the liver ? Venous. 
 
 In what blood is sugar found ? Blood from the liver to 
 the lungs. 
 
 What becomes of it? It is destroyed in the lungs. 
 
 Is it ever deposited? No. 
 
 It is supposed to have to do with what? With the pro- 
 duction of fats. 
 
 Why think so ? Fat and sugar have the same elements, 
 and people using much sugar grow fat. 
 
 What elements make up sugar? Carbon, hydrogen and 
 oxvsren. 
 
152 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Is sugar normally found in the blood going to the liver ? 
 No. 
 
 Is it found in that going from the liver? It is. 
 
 What would that indicate? That it is formed in the liver. 
 
 Does the liver contain sugar during life ? It does not. 
 
 Proof? As soon as an animal is killed, test for the sugar 
 and will not find it. 
 
 In what time must it be tested ? In ten seconds. 
 
 Give the characters of liver sugar? It ferments more 
 readily than other sugar. 
 
 Give the mechanism of the production of sugar in the 
 liver ? The hepatic ferment acts on the glycogen. 
 
 What is the first organ to produce sugar ? The placenta. 
 
 What influence has digestion on the production of su- 
 gar? It increases it. 
 
 Has diet any effect ? Yes. Some increase and others 
 lessen it. 
 
 What is the destination of sugar ? It is destroyed in the 
 lungs. 
 
 What kind of bread do you use in glycosuria ? Bread 
 made of gluten. 
 
 Why? It has a variety of principles. 
 
 How is sugar production influenced by cutting the pneu- 
 mogastric between lungs and liver ? Not affected. 
 
 Between the origin and lungs ? It is not affected. 
 
 Effect of irritation of the fourth ventricle of the brain ? 
 Causes diabetes mellitus. 
 
 Effect of stimulating the peripheral extremity of cut 
 nerve in neck ? Has no effect. 
 
 Stimulating the central end ? Increases the sugar. 
 
 Through what system of nerves is it transmitted ? Sym- 
 pathetic. 
 
 What effect has the inhalation of anaesthetics ? Increases 
 the sugar in the urine. 
 
DUCTLESS GLANDS. 1 53 
 
 CHAPTER XXX. 
 
 DUCTLESS GLANDS. 
 
 Is the spleen essential to life ? Ans. It is not. 
 
 Proof? Can do without it. 
 
 What is it thought to have to do with the manufacturing 
 of leucocytes? Leucocytes are found in greater number in 
 the splenic vein than artery. 
 
 What is the liver thought to have to do with destruction 
 of red ? The}' are found in diminished quantity in the he- 
 patic vein. 
 
 Why is the spleen thought to act as a diverticulum for 
 the blood during digestion ? It is found full of blood at 
 this time. 
 
 How is the appetite when the spleen is removed? It is 
 very much increased. 
 
 In what trouble is the spleen enlarged? Malaria. 
 
 Where do you find the suprarenal capsule ? Above and 
 in close apposition with the kidney. 
 
 Is its function known ? It is not. 
 
 In what trouble are they diseased? Addison's disease. 
 
 Are they essential to life ? They are not. 
 
 Where do you find the thyroid gland ? One lobe on 
 each side of the trachea. 
 
 Is it essential to life ? No. 
 
 Is its function known ? No. 
 
 What is enlargement of it called ? Goitre or broncho- 
 celle. 
 
 When is it largest in the female ? At the menstrual 
 period. 
 
 At what period of life is the thymus gland largest ? In 
 foetal life. 
 
154 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XXXI. 
 
 NUTRITION. 
 
 What is nutrition ? Ans. Appropriating new material for 
 the waste of the old. 
 
 What becomes of all tissue ? It wears out. 
 
 What parts when they wear out are not carried by the 
 blood to the organs for elimination? False skin and its 
 appendages. 
 
 How are they gotten rid of? They are exfoliated. 
 
 What trouble would there be if these effete materials 
 were not eliminated ? The system would become poisoned. 
 
 What was the first process of nutrition that we studied ? 
 Circulation of the blood. 
 
 What does the blood contain? All the elements neces- 
 sary for nutrition. 
 
 What was the second process we studied? Respiration. 
 
 What is respiration? The process by which the tissues 
 receive oxygen and give off carbonic acid. 
 
 What is the relation of respiration to nutrition ? Direct. 
 
 How long would we live without oxygen ? Three to 
 seven minutes. 
 
 What is the third act ? Alimentation. 
 
 What classes of food are essential to life? Organic, ni- 
 trogenized and inorganic. 
 
 How long would we live without food ? About forty days. 
 
 What is the fourth act? Deglutition. 
 
 What is deglutition ? The act of swallowing. 
 
 How is it divided ? Into three acts. 
 
 What is the fifth act ? Digestion. 
 
 What is digestion ? Liquefaction of the food. 
 
 Where does it begin? In the mouth. 
 
 Where end ? In the small intestines. 
 
NUTRITION. 155 
 
 What is the first object of digestion ? Liquefaction of the 
 food. 
 
 What is the second object of digestion? To prepare the 
 food for absorption. 
 
 By what vessels is absorption carried on ? Veins and 
 lymphatics. 
 
 What is absorbed by the veins ? All that will form a ho- 
 mogeneous mass with the blood. 
 
 What by the lymphatics ? All the rest. 
 
 What is the sixth act of nutrition ? Secretion. 
 
 What is a secretion ? Something manufactured in a gland . 
 
 How are they divided ? Permanent and transitory secre- 
 tions. ■ 
 
 What is tha function of the permanent ? To lubricate. 
 
 Of the transitory? To aid in digestion. 
 
 Are they discharged from the organism ? No. 
 
 What is the seventh act of nutrition? Excretion. 
 
 What trouble if excretions are disturbed ? The system 
 becomes poisoned. 
 
 What is an excretion? Something discharged from the 
 body. 
 
 What principles pass through the organism unchanged ? 
 The inorganic. 
 
 How many are there ? Twenty-one. 
 
 Name the gases? Oxygen, nitrogen, hydrogen, sulphur- 
 etted and carburetted hydrogen. 
 
 Where are oxygen and hydrogen found ? Everywhere. 
 
 Where is nitrogen found ? In all tissue. 
 
 Where are carburetted hydrogen and sulphuretted hy- 
 drogen found ? In the alimentary canal. 
 
 Which is essential ? Oxygen. 
 
 What is most imperative after oxygen ? Water. 
 
 Where do you find it ? Everywhere. 
 
 What regulates the amount ? Chloride of sodium. 
 
156 COMPEND OF HUMAN PHYSIOLOGY. 
 
 How can you tell when there is too little ? Become 
 thirsty. 
 
 If too much ? HaYe dropsy. 
 
 What is the function of water ? It acts as a solvent for 
 the salts, gives elasticity to cartilage, contractility to muscle, 
 densit}^ to bone and pliability to tendons. 
 
 What is the origin of water ? From within and without 
 the body. 
 
 Why think it is formed in the body ? There is more dis- 
 charged than taken in. 
 
 How much is discharged by the kidneys daily ? Fifty- 
 two ounces. 
 
 By the lungs ? One and one-fifth pounds. 
 
 How much water is there in the blood? About eight 
 hundred parts. 
 
 Where is chloride of sodium found ? Everywhere except 
 in the enamel of the teeth. 
 
 Is there more in solids or fluids ? Fluids. 
 
 How much is there in the blood? Three to four parts per 
 thousand. 
 
 How much in urine? Three to eight parts. 
 
 What is the origin of chloride of sodium ? Introduced 
 from without. 
 
 How is it discharged? Sweat, urine and mucus. 
 
 What is the function of chloride of sodium ? To give 
 density to the plasma, aid in osmosis and determine transu- 
 dation. 
 
 What is the origin of chloride of potash ? From without 
 and from double decomposition within. 
 
 How is it discharged ? In mucus and urine. 
 
 What is its function ? Same as chloride of sodium. 
 
 Where is phosphate of lime found ? In all the solids and 
 fluids of the body. 
 
 Is there more in solids or fluids ? Solids. 
 
NUTRITION. 157 
 
 Is it very soluble ? No. 
 
 What holds it in solution ? The carbonic acid and car- 
 bonates. 
 
 It is found especially in what tissue ? Bony tissue. 
 
 In what bones is it in greatest quantity ? Those of the 
 lower extremity. 
 
 Why? So that they can sustain the weight of the body. 
 
 At what period of life is there most ? Old age. 
 
 Why? There is a deficiency of its elimination at this time. 
 
 When are fractures most liable ? In old age. 
 
 Why ? The bones are more brittle. 
 
 What is the origin of phosphate of lime ? Introduced 
 from without. 
 
 How is it eliminated ? In the urine and faeces. 
 
 What is its function ? To give to the bones their power 
 of resistance. 
 
 What is the function of the other phosphates? The same. 
 
 Where is carbonate of lime found? Blood, bones, teeth, 
 cartilage and internal ear. 
 
 How does it differ from the other salts in the organism, 
 in its form ? It is found in the crystalline form in the in- 
 ternal ear. 
 
 What is its function ? Thought to have to do with audi- 
 tion. 
 
 What is its origin ? Introduced from without and formed 
 within. 
 
 How is it discharged? In the urine as phosphate of lime. 
 
 Is carbonate of soda ever introduced as such ? No. 
 
 How is it formed ? By the decomposition of tartrates, 
 malates, etc. 
 
 What is its function ? To preserve the fluidity of the 
 albuminoids and the consistency of the corpuscles. 
 
 What is the function of the sulphates ? Same as carbon- 
 ate of soda. 
 
150 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What is the origin of sulphates? Introduced from without. 
 
 Name the principles consumed in the organism? The 
 organic. 
 
 How are they divided? Into nitrogeuized and non-ni- 
 trogenized. 
 
 Name the nitrogenized class? Albumin, musculin, ca- 
 sein, etc. 
 
 What is another name for this class ? Albuminoids or 
 plastics. 
 
 What elements are in this class? Carbon, hydrogen, 
 oxygen, nitrogen and sulphur. 
 
 Do they produce fats ? No. 
 
 What do they produce ? Muscular tissue. 
 
 What tissue is especially nourished by nitrogenized diet ? 
 Muscular tissue. 
 
 How is urea influenced by nitrogenized diet ? It is in- 
 creased in amount. 
 
 What is the object in training? To introduce nitrogen- 
 ized food enough to compensate the waste and to take a 
 moderate amount of exercise. 
 
 Power resides in what kind of tissue ? Muscular tissue. 
 
 What is crystalline ? The nitrogenized substance found 
 in the crystalline lens. 
 
 What is myosin ? Nitrogenized substance of muscles. 
 
 What is keratin? That of the epidermis and its append- 
 ages. 
 
 What is elastin ? That of elastic tissue. 
 
 Ossein ? That of bones. 
 
 Gelatine ? That of fibrous tissue. 
 
 What is meant by metabolism ? The changes in the tis- 
 sue in digestion. 
 
 Name the non-nitrogenized food? Sugar, starch and fat. 
 
 What is another name for this class ? Calorifics. 
 
 Are the non-nitrogenized principles essential to life:* Xo. 
 
 
NUTRITION. 159 
 
 Why are they called calorifics ? They are supposed to 
 have to do with keeping up animal temperature. 
 
 Are they essential to normal temperature ? No. 
 
 When are they most called for ? In winter. 
 
 When is fat deposited in the tissue ? When an excess of 
 food has been taken in. 
 
 Is there any power in fatty tissue ? No. 
 
 If deprived of food, which lives longest, a fat or lean 
 person ? Fat one. 
 
 What part of the tissue is first used up ? The fat. 
 
 Is fat formed in the body ? It is. 
 
 Reason for thinking so ? A person can get fat without 
 the introduction of fat. 
 
 Give reasons why think sugar produces fat ? They con- 
 tain the same elements, and people using much sugar grow 
 fat. 
 
 How is fat found in the body? As adipose tissue. 
 
 Give its physiological anatomy? A nitrogenized net 
 work in which are held oil globules. 
 
 Are there any nerves or lymphatics in fatty tissue ? There 
 are not. 
 
160 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XXXII. 
 
 ANIMAL HEAT. 
 
 How many heat units are produced by each pound per 
 hour? Ans. Four. 
 
 What is the normal temperature ? Ninety-eight and one- 
 half degrees Fahrenheit. 
 
 Give the variations ? One-half degree Fahrenheit below 
 and one degree above that. 
 
 Give the variations with the external temperature? 
 Eighty three degrees Fahrenheit and one hundred and seven 
 degrees Fahrenheit. 
 
 On which side of the heart is the blood warmest ? Right. 
 
 Why ? It has not been cooled in passing through the lungs. 
 
 What is the warmest blood in the body ? That of the 
 hepatic vein. 
 
 What is its temperature? One hundred and seven de- 
 grees Fahrenheit. 
 
 Is it warmer in the portal vein or abdominal aorta? 
 Portal vein. 
 
 What period of our life is the temperature lowest? Just 
 after birth. 
 
 At what period do we resist cold least ? In early life. 
 
 At what period of the day is the temperature highest ? 
 At ii A. m. and 4 p. m. 
 
 What effect has fasting on the temperature ? It lowers it. 
 
 Why? You have defective nutrition at this time. 
 
 What effect has exercise on it ? It increases it. 
 
 What is the source of heat ? The oxidation of tissue. 
 
 What was the old idea of its cause ? That it was pro- 
 duced by some special organ. 
 
 What relation has heat to nutrition and to respiration ? 
 Direct. 
 
 
ANIMAL HEAT. l6l 
 
 Why is it thought that water is formed in the body? 
 Because less is taken in than is discharged. 
 
 What favors its formation? Exercise. 
 
 What is the relation of exercise to the temperature ? 
 Direct. 
 
 Why is it necessary to assume that water is formed in 
 the organism ? There is no other way of accounting for the 
 oxygen which is lost in respiration. 
 
 In what way is heat produced ? By the oxidation of car- 
 bon, hydrogen and oxygen. 
 
 The heat value of which one is greatest? Hydrogen. 
 
 Could the amount of heat that any given quantity of 
 food would produce be estimated ? It could. 
 
 How ? By burning it in oxygen. 
 
 How much food should be introduced ? Just enough to 
 compensate the waste. 
 
 If less is introduced than would keep up the tempera- 
 ture of the body, what change takes place ? Body becomes 
 emaciated. 
 
 What if more is introduced ? Becomes fat. 
 
 Is the food oxidized ? It is not. 
 
 What becomes of the food ? It is appropriated. 
 
 How does digestion influence temperature ? By aiding 
 nutrition. 
 
 What is the relation of the temperature of the body to 
 the heat produced ? It is lower. 
 
 What becomes of the excess of heat ? It goes to form 
 force. 
 
 In what way is the temperature equalized in the human 
 being ? By clothing. 
 
 What kinds are worn in summer ? Linen . 
 
 Why ? It is a good conductor for heat. 
 
 Kind used in winter? Woolen. 
 
 Why? It is a bad conductor and keeps the heat in. 
 
 n 
 
1 62 COMPEND OF HUMAN PHYSIOLOGY. 
 
 If find a patient with sub-normal temperature, what med- 
 icine would be given? Belladonna. 
 
 Why ? It elevates the temperature slightly. 
 
 How does it do it ? It increases the blood to the heat- 
 gaining area. 
 
 What is the heat-losing area ? The superficial surface. 
 
 What is the heat-producing area? The interior of the 
 body. 
 
 In a warm room what is the condition of the blood sup- 
 ply to the heat-losing area? It is increased. 
 
 How is it to the heat-producing area ? It is lessened. 
 
 When going into the cold, what is the first effect? Skin 
 gets red. 
 
 What does the heat-producing area do? Gets more 
 blood. 
 
 When reaction takes place, how is the skin ? Pale. 
 
 How does it influence the heat loss ? Lessens it. 
 
 What does it cause ? Congestion of the internal organs. 
 
 What name is given to this? Catching cold. 
 
 What part is affected? The mucous membrane of the 
 respiratory passages. 
 
 Is it always limited to the respiratory passages? No. 
 
 What influence has alcohol on temperature ? It lowers it. 
 
 Why ? It carries elements to the tissues to be oxidized 
 instead of the tissue, and it also increases the blood to the 
 heat-losing area. 
 
 Why does it cause a feeling of warmth? The blood to 
 the skin is increased. 
 
 Through what do we take cognizance of heat and cold ? 
 The sensory nerves on the surface. 
 
 What kind of sensation is there during a chill? Cold. 
 
 How is the temperature ? Elevated. 
 
 Why do we feel cold ? The blood to the surface is less 
 ened. 
 
 
NERVOUS SYSTEM. 163 
 
 CHAPTER XXXIII. 
 
 NERVOUS SYSTEM. 
 
 How is the nervous system divided ? A)is. Into cerebro- 
 spinal and sympathetic. 
 
 What is the cerebro-spinal ? The brain and cord, and 
 nerves coining from them. 
 
 Over what does it preside ? The functions of animal life. 
 
 What is the sympathetic ? The ganglionic system. 
 
 Over what does it preside ? The functions relating to nu- 
 trition. 
 
 How is nerve matter divided ? Into cells and fibres. 
 
 What is the color of a nerve cell ? Gray. 
 
 Of a nerve fibre ? White. 
 
 What is the function of a cell? To generate force. 
 
 Of a fibre ? To conduct force. 
 
 Are cells excitable? No. 
 
 Give the exceptions ? The sympathetic ganglia and cer- 
 tain centers in the brain and cord. 
 
 What is necessary for a cell to generate force ? It must 
 receive a stimulus. 
 
 How are nerve fibres divided? Medullated and non- 
 medullated fibres. 
 
 Name the parts of a medullated fibre ? White sheath and 
 substance of Schwann and axis-cylinder. 
 
 What is the name given the sheath? White sheath of 
 Schwann. 
 
 Give its anatomy? An elastic homogeneous membrane 
 with oval nuclei. 
 
 Where* is the sheath absent ? In the white part of the 
 brain and cord. 
 
 Name of the medullary substance ? White substance ot 
 Schwann. 
 
164 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Where is it absent ? At the beginning and termination of 
 nerves. 
 
 What is the function of the sheath and medulla ? They 
 act as an insulator for the cylinder. 
 
 What is the axis-cylinder ? The central flattened band. 
 
 In what nerves is it absent ? In the nerves of Remak. 
 
 Where is it not surrounded by the sheath and medullary 
 substance ? Where the nerves terminate. 
 
 How can the axis-cylinder be demonstrated ? By apply- 
 ing acetic acid to the cut end. 
 
 What is its function? To conduct force. 
 
 Where are the nerves of Remak found ? In the sympa- 
 thetic system. 
 
 They are connected with what movements ? Involuntary. 
 
 What is the color of these fibres ? Gray. 
 
 They resemble what nerves ? Embryonic nerves. 
 
 Name the anatomical accessory elements of a nerve ? 
 Connective tissue, blood-vessels and lymphatics. 
 
 Where greatest? Between the muscles. 
 
 Why? For protection. 
 
 Describe the blood supply to a nerve ? The arteries break 
 up into a delicate plexus, which are arranged in longitudinal 
 meshes around the fibres. 
 
 Do nerves contain lymphatics ? It is supposed so. 
 
 What is the function of these accessory elements ? To 
 furnish nutrition and afford protection. 
 
 Do nerves anastomose ? They do. 
 
 Where? Near their termination. 
 
 What is the peri nerve ? Membrane around several fas- 
 
 iculi. 
 
 What is the neurilemma? Membrane around a bundle of 
 
 nerves. 
 
 How do nerves terminate in voluntary muscular fibres ? 
 
 Neurilemma and sarcolemma become continuous, the medul- 
 
NERVOUS SYSTEM. 1 65 
 
 lary substance stops and the axis-cylinder enters and termi- 
 nates in an end plate. 
 
 How in glands ? Form a plexus and pass directly to the 
 crlandular cells and terminate in the nucleoli. 
 
 o 
 
 How do they terminate in involuntary muscular fibres ? 
 
 Form a plexus in the connective tissue around the muscle 
 and send branches into the nucleoli. 
 
 How do sensory nerves end ? In integument and in mu- 
 cous membrane. 
 
 Where do you find the corpuscles of Vater ? Palms of 
 the hands, soles of the feet and palmar surface of the fingers. 
 
 What is their shape ? Oval. 
 
 What is their relation to the skin ? They are beneath 
 the skin. 
 
 Describe the termination of nerves in them ? The neuri- 
 lemma surrounds the corpuscle, the medullary substance 
 stops, and the axis-cylinder penetrates the bulb. 
 
 What is their function ? Have to do with general sensi- 
 bility. 
 
 Where are the tactile corpuscles ? Palms of the hands, 
 soles of the feet, nipple, and front of the forearm. 
 
 In what layer of the skin ? Papillary. 
 
 In what kind of papilla? ? Compound. 
 
 Describe the corpuscles ? Oblong, with the long diameter 
 in the direction of the papillae; the nerve winds around them 
 two or three times and terminates in a pale extremity. 
 
 What is their function ? Have to do with the sense of 
 touch. 
 
 Where are the terminalbulbs ? Conjunctiva, buccal cav- 
 ity, tongue, glans penis and clitoris. 
 
 What shape are they ? Round. 
 
 How do nerves terminate in them ? The sheath is con- 
 tinuous with the membrane around the corpuscle, and the 
 axis-cylinder penetrates and terminates in a knotted coil. 
 
1 66 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What is their function? Have to do with general sensi- 
 bility. 
 
 In what other way do sensory nerves terminate on the 
 skin ? In hair follicles and free extremities. 
 
 How do they terminate on mucous membranes ? They 
 form a plexus beneath the epithelium. 
 
 Name the different kinds of nerve cells ? Apolar, unipo- 
 lar, bipolar, and multipolar. 
 
 Where do you find the apolar cells? In lower animals. 
 
 Where do you find the unipolar and bipolar ? In the 
 ganglia of the cranial nerves and posterior roots of spinal 
 nerves. 
 
 What is meant by multipolar cells ? Those with three 
 or more poles. 
 
 Name the kinds? Large and small. 
 
 Where find the small ? Posterior gray cornua of the cord. 
 
 Where find the large ? Anterior gray cornua. 
 
 With what are the poles continuous ? With the axis- 
 cylinder. 
 
 How are the poles connected with the cell ? By proto- 
 plasmic prolongations. 
 
 How are the cells connected together ? By their poles. 
 
 What is the color of a nerve cell ? Gray. 
 
 Name the accessory elements of a cell ? On outer cover- 
 ing, intercellular granular matter, myelocytes, connective 
 tissue, blood vessels and lymphatics. 
 
 Give the composition of nerve matter ? Cerebrin, pro- 
 tagon, lecithin, xanthine, cholesterin, etc. 
 
 If a nerve is cut, is it reproduced? It is. 
 
 Describe the new nerve ? Like other nerves, except that 
 it has no axis-cylinder. 
 
 If nerve cells are destroyed, are they reproduced ? No. 
 
 What is meant by a motor nerve ? One that carries a 
 force to the muscles that causes them to contract. 
 
NERVOUS SYSTEM. 1 67 
 
 What is their function ? To give motion to the muscles. 
 
 In what direction do they act? From the center to the 
 periphery. 
 
 If they are stimulated, what follows ? Motion. 
 
 Will motor nerves respond to a stimulus ? They will. 
 
 What will paralyze motor nerves ? Curare. 
 
 How do they die ? From center to the surface. 
 
 If cut, what is the last part to die ? The periphery. 
 
 In what time ? Several hours. 
 
 What is meant by a sensory nerve ? One that carries a 
 force that causes pain. 
 
 If it is irritated, what does it cause ? Pain. 
 
 Where is the impression sent? To the brain. 
 
 In what direction is it sent ? From center to periphery. 
 
 What receives the impression? The centers in the brain. 
 
 What is generated ? Force. 
 
 What will paralyze ssnsory nerves? Anaesthetics. 
 
 In what direction do they act ? From periphery to the 
 center. 
 
 Why must more chloroform be given in a deep than su- 
 perficial operation ? Because the deep parts are last affected. 
 
 What will paralyze muscular irritability? Sulpho-cya- 
 nide of potash. 
 
 How many roots have spinal nerves ? Two. 
 
 Which is largest ? The posterior. 
 
 What is peculiar about the posterior root ? It has a 
 ganglion. 
 
 Where does it unite ? As it leaves the intervertebral fora- 
 men. 
 
 What does it. form ? A mixed nerve. 
 
 Which root is motor ? Anterior. 
 
 Proof? Cut it and will have muscular paralysis. 
 
 Which is sensory ? Posterior. 
 
 Proof? Stimulate it and will have pain. 
 
1 68 COMPEND OF HUMAN PHYSIOLOGY. 
 
 If the anterior root is stimulated, why is there slight pain? 
 
 There are filaments of communication between the anterior 
 and posterior root. 
 
 "Where are the posterior roots largest ? At the ganglion. 
 
 What is reflex action ? Action sent back. 
 
 Explain it ? The impression is made on the sensory nerves 
 and is carried to the center, where force is generated and sent 
 back over the motor nerves. 
 
 CHAPTER XXXIV. 
 
 CRANIAL NERVES. 
 
 What is meant by cranial nerves ? Ans. Those passing 
 through the cranium. 
 
 Do they all arise in the cranium ? They do not. 
 
 Which does not? The spinal accessory nerve. 
 
 How are they classified ? Into motor and sensory nerves 
 and nerves of special sense. 
 
 What is the other name for the third nerve ? Motor 
 Oculi communis. 
 
 What is its origin ? On the inside of the crura cerebri in 
 front of the pons Varolii. 
 
 With what does it communicate ? The ophthalmic division 
 of the fifth. 
 
 To what is it distributed ? All the muscles of the eye ex- 
 cept the superior oblique and external rectus. 
 
 What kind of nerve is it at its origin ? Motor. 
 
 Before its distribution how is it ? Mixed. 
 
 What symptoms are produced by cutting the third nerve ? 
 Phthosis, external strabismus, pupil dilated and directed 
 down and outward. 
 
CRANIAL NERVES. 1 69. 
 
 Why does the upper lid fall ? The levator palpebrae is 
 paralyzed. 
 
 Why does the pupil dilate ? The circular fibres of the iris 
 are paralyzed. 
 
 Does the third nerve supply the iris directly ? No. 
 
 How does it? Through the lenticular ganglion. 
 
 What direction have the fibres of the iris ? Circular and 
 radiating. 
 
 What nerve supplies the circular ? The third nerve. 
 
 What supplies the radiating ? Sympathetic. 
 
 What is the condition of the pupil of the eye if the third 
 nerve is stimulated? Contracted. 
 
 If cut, how is it ? Dilated. 
 
 Why does opium contract the pupil ? It stimulates the 
 third nerve. 
 
 Why will belladonna cause it to dilate? It stimulates 
 the sympathetic and paralyzes the third. 
 
 How is the pupil directed when the third nerve is cut ? 
 Downward and outward. 
 
 Why ? The eye ball is pulled upward and inward by the 
 superior oblique muscle. 
 
 What is the other name for the fourth nerve ? Pathet- 
 icus. 
 
 What is its origin? Valve of Vieussens near the testes. 
 
 Its distribution ? To the superior oblique muscle. 
 
 With what does it communicate ? The ophthalmic nerve. 
 
 Is it motor or sensory at its origin ? Motor. 
 
 How is it at its distribution ? Mixed. 
 
 What is the origin of the sensory filaments ? From the 
 ophthalmic. 
 
 What are the symptoms if the fourth nerve is cut ? Pupil 
 is directed upward and outward. 
 
 Why ? The inferior oblique muscle pulls the globe down- 
 ward and inward. 
 
170 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What is the other name for the sixth nerve ? Abducens. 
 
 What is its origin? The upper part of the corpus pyra- 
 m i dale. 
 
 To what is it distributed ? The external rectus muscle. 
 
 What is the origin of its sensory filaments? From the 
 ophthalmic. 
 
 What are the symptoms if it is cut? Internal strabis- 
 mus. 
 
 Why? The external rectus muscle is paralyzed and the 
 internal pulls the eye in. 
 
 What is the other name for the fifth ? Tri-facial. 
 
 How many roots has it ? Two. 
 
 Name them ? Anterior and posterior. 
 
 Which is largest ? The posterior. 
 
 How many filaments in it? Seventy-five to one hundred. 
 
 What does the posterior root do? It forms a ganglion. 
 
 What is the origin of the fifth nerve ? From the lateral 
 portion of the pons Varolii. 
 
 What are the branches of the Gasserian ganglion? Su- 
 perior and inferior maxillary and ophthalmic. 
 
 With what does the inferior maxillary unite ? With the 
 motor root. 
 
 Where ? Just before it gets out of the cranium. 
 
 Through what foramen does it pass ? Foramen ovale. 
 
 What are its branches ? External and internal. 
 
 What does the external supply ? All the muscles of mas- 
 tication except the buccinator. 
 
 What does the internal supply? Mylo-hyoid and ante- 
 rior belly of the digastric muscle. 
 
 What is the nerve of mastication ? The motor root of the 
 fifth. 
 
 To what muscles is it distributed ? The muscles of mas- 
 tication except the buccinator. 
 
 What supplies the buccinator ? The facial nerve. 
 
CRANIAL NERVES. 171 
 
 What are the symptoms if the nerve of mastication is 
 cut ? Paralysis of the muscles of mastication. 
 
 Why will a rabbit die when it is cut? It cau't close its 
 mouth. 
 
 Why will the teeth grow long ? They are not worn off by 
 mastication. 
 
 In what way is deglutition impaired by cutting the small 
 root of the fifth ? It interferes with the elevation of the os 
 hyoides. 
 
 Why? Because the mylo-hyoid and anterior belly of the 
 digastric are paralyzed. 
 
 Is the internal branch wholly sensory ? It is not. 
 
 What muscles do the motor filaments supply? Mylo- 
 hyoid and anterior belly of the digastric. 
 
 What is the other name for the facial ? Portio dura. 
 
 What is its origin ? Between the corpus olivary and resti- 
 formia. 
 
 Where does the facial nerve decussate ? In the pons 
 Varolii. 
 
 If there is an injury of the brain involving the facial 
 nerve before its decussation, where is the facial paralysis ? 
 On the opposite side of the injury. 
 
 Where is the hemiplegia ? On the same side as the lesion 
 and opposite side of the facial paralysis. 
 
 If it is injured after the decussation, where is the facial 
 paralysis ? On the same side as the lesion and opposite side 
 of the hemiplegia. 
 
 What is the peculiarity of the facial nerve? It has a 
 ganglion. 
 
 Where is it ? In the hiatus Fallopii. 
 
 What is it called ? Intumescentia gangliformis. 
 
 What is the course of the facial nerve ? Toward the ear. 
 
 With what does it first communicate ? The nervus petro- 
 sus superficialis major. 
 
172 COMPEND OF HUMAN PHYSIOLOGY. 
 
 With what next? Nervus petrosis superficialis minor. 
 
 What is its third commnnication ? Auricular branch of 
 the pneumogastric. 
 
 What does it give to the pneumogastric ? Motor filaments. 
 
 What does it get from the pneumogastric ? Sensory 
 filaments. 
 
 What muscle does the tympanic branch of the facial 
 supply? The stapedius muscle. 
 
 Where does the chorda tympani go ? To the tongue. 
 
 What are the terminal branches of the facial nerve ? 
 Temporo-facial and cervico-facial. 
 
 To what are they distributed ? The face from the chin to 
 summit of the head. 
 
 What kind of nerve is the facial at its origin ? Motor. 
 
 Before its distribution ? Mixed. 
 
 What is the origin of the sensory filaments ? From the 
 pneumogastric. 
 
 What branch is a nerve of special sense ? Chorda tym- 
 pani. 
 
 What nerves have ganglia ? Sensory nerves and those of 
 special sense. 
 
 What is the portio intermedia ? The nerve of Wrisberg. 
 
 What is its origin ? In the groove between the corpus 
 olivary and restiformia. 
 
 With what does it unite ? The facial. 
 
 What ganglion do they form ? Intnmescentia gangli- 
 formis. 
 
 What is the real origin of the chorda tympani ? Between 
 the corpus olivary and restiformia. 
 
 To what is it distributed ? To the tongue. 
 
 What is its function ? To give taste to the anterior part 
 of the tongue. 
 
 What are the symptoms if it is cut ? Would have loss of 
 taste at that part. 
 
SPINAL ACCESSORY. 1 73 
 
 What gives the taste to the back part of the tongue ? The 
 glosso-pharyugeal nerve. 
 
 How is mastication affected by cutting the facial nerve ? 
 Caii not keep the food on the teeth. 
 
 Why? Because the buccinator and orbicularis muscles 
 are paralyzed. 
 
 How is deglutition affected? The second act is impaired. 
 
 Why ? The posterior belly of the digastric and the stylo- 
 hyoid muscles are paralyzed. 
 
 What part of the second act is impaired ? The first part. 
 
 What is the function of the terminal branches of the 
 facial nerve ? To give motion to the muscles of the face. 
 
 What are the symptoms if cut ? Paralysis of the muscles 
 of the face. 
 
 CHAPTER XXXV. 
 
 SPINAL ACCESSORY. 
 
 How many roots has it ? Ans. Two. 
 
 What is the origin of the upper ? Medulla oblongata. 
 
 How does it get into the cranium ? Through the foramen 
 magnum. 
 
 How does it get out ? Through the jugular foramen. 
 
 Into what branches does it divide ? External and in- 
 ternal. 
 
 What does the external supply ? Trapezius and sterno- 
 cleido- mastoid muscles. 
 
 With what does the internal unite ? The pneumogastric. 
 
 What kind of a nerve is it at its origin ? Motor. 
 
 How is it at its distribution? Mixed. 
 
 What are the symptoms if the lower root is cut ? Pa- 
 ralysis of the sterno-cleido-mastoid and trapezius muscles. 
 
IJ4 COMPEND OF HUMAN PHYSIOLOGY. 
 
 How is respiration affected ? It is impeded. 
 
 Give the symptoms if the upper root is cut ? Loss of 
 voice, heart beats faster and the second act of deglutition in- 
 terfered with. 
 
 How is the voice if one nerve is cut ? Hoarse. 
 
 How if both are cut ? Lost. 
 
 What act of deglutition is impaired ? The second. 
 
 Why ? The constrictor muscles of the pharynx are para- 
 lyzed. 
 
 Why does the heart beat faster ? The inhibitory action 
 of the pneumogastric nerve is destroyed. 
 
 If the spinal accessory nerve is cut on one side and elec- 
 tricity applied to the pneumogastric, what will be the ef- 
 fect? The heart stops beating. 
 
 How long before the heart is influenced? Nine or ten 
 days. 
 
 CHAPTER XXXVI. 
 
 HYPOGLOSSAL. 
 
 What is its origin ? Ans. Between the corpus olivary 
 and pyramidale. 
 
 How does it get out of the cranium? Through the an- 
 terior condyloid foramen. 
 
 What are its branches ? Descendens noni, thy ro-li void 
 and muscular. 
 
 What organ is supplied by it ? The tongue. 
 
 What kind of nerve is it at its origin ? Motor. 
 
 How at its distribution ? Mixed. 
 
 What are the symptoms if it is cut ? Paralysis of the 
 tongue. 
 
 How is mastication influenced? Can't pull the jaw down. 
 
 Why ? The depressors of the os-hyoids are paralyzed. 
 
TRI-FACIAL. 175 
 
 CHAPTER XXXVII. 
 
 TRI-FACIAL. 
 
 What kind of nerve is the posterior root ? Ans. Sen- 
 sory. 
 
 To what is it distributed ? To the face. 
 
 What are the symptoms if it is cut posterior to the gan- 
 glion ? Loss of sensation to the parts that it is distributed. 
 
 What symptoms if cut the ganglion or anterior to it? 
 Loss of sensation and purulent inflammation of the eyes. 
 
 Why ? Because you have bad nutrition together with 
 increased blood supply to the face. 
 
 Why is nutrition bad? Can't masticate. 
 
 Why can't one masticate ? In cutting the posterior root 
 the anterior is always cut and the muscles of mastication are 
 paralyzed. 
 
 Why are the blood-vessels dilated ? The vaso-motor con- 
 strictor nerves to the blood-vessels of the face pass up from 
 the neck through the ganglion, and when they are cut the 
 blood supply is increased. 
 
 If irritation is applied to the soft palate, what act is ex- 
 cited ? Deglutition. 
 
 How is it brought about ? The impression is made on the 
 tri-facial, one of the reflex nerves of deglutition which car- 
 ries it to the center, where force is generated which causes 
 efforts at deglutition. 
 
 What effect has cutting of the tri-facial ? One of the re- 
 flex nerves of deglutition is paralyzed, which interferes 
 with deglutition. 
 
 How many reflex nerves of deglutition are there? Two. 
 
 Name them ? Superior laryngeal and tri-facial. 
 
 Why was the fifth nerve called tri-facial ? Because it 
 makes its appearance at three places on the face. 
 
176 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XXXVIII. 
 
 PNEUMOGASTRIC. 
 
 What is its origin ? Arts. Between the corpus restifor- 
 mia and olivary. 
 
 How does it get out of the cranium ? Through the jugu- 
 lar foramen. 
 
 What kind of nerve is it at its origin ? Sensor)'. 
 
 How is it at its distribution ? Mixed. 
 
 What is the source of the motor filaments ? Spinal ac- 
 cessory and facial. 
 
 Give its communications? Spinal accessory, facial and 
 sympathetic. 
 
 What is its first branch ? Auricular. 
 
 What are the communications of the auricular ? Facial 
 and glossopharyngeal. 
 
 To what is it distributed ? External auditory meatus and 
 membrana tympani. 
 
 What is it function ? To give sensation to the parts. 
 
 What is the second branch of the pneumogastric ? Pha- 
 ryngeal. 
 
 What plexus does it help to form? The pharyngeal 
 plexus. 
 
 What forms the pharyngeal plexus? The pharyngeal 
 branches of the pneumogastric and glosso-pharyngeal and the 
 symphathetic. 
 
 What does the plexus supply? The muscles of the 
 pharynx. 
 
 The motor filaments of the plexus comes from which 
 branch ? Pharyngeal branch of the pneumogastric. 
 
 What is the real source? The spinal accessory. 
 
 Which root of the spinal accessory ? Upper. 
 
PNEUMOGASTRIC. 1 77 
 
 What are the symptoms if the pharyngeal branch of the 
 pneumogastric is cut? The muscles of the pharynx are 
 paralyzed. 
 
 What if the upper root of the spinal accessory is cut ? 
 Same symptoms. 
 
 What is the third branch of the pneumogastric? Supe- 
 rior laryngeal. 
 
 To what organ is it distributed ? I^arynx at the upper 
 part. 
 
 What is its function? To give sensation to that part so 
 as to protect the larynx during deglutition. 
 
 During what act of deglutition ? The second act. 
 
 What are the symptoms if it is cut? L,ossof sensation to 
 the mucous membrane of the larynx and one of the reflex 
 nerves of deglutition is destroyed. 
 
 What if stimulated? Will make efforts at deglutition 
 and cough. 
 
 By cutting it, how is deglutition influenced? It is 
 interfered with, as one of the reflex nerves of deglutition is 
 cut. 
 
 What branch does the superior laryngeal nerve give off ? 
 The external laryngeal. 
 
 To what is it distributed ? The inferior constrictor of the 
 pharynx and crico-thyroid muscles and the thyroid gland. 
 
 With what does it communicate ? Inferior laryngeal and 
 sympathetic. 
 
 What is the function of the external laryngeal branch ? 
 To animate the crico-thyroid and the inferior constrictor of 
 the pharynx. 
 
 What is the fourth branch of the pneumogastric ? In- 
 ferior laryngeal. 
 
 What is its other name? Recurrent laryngeal. 
 
 What is its course on the left side ? Around the arch of 
 the aorta. 
 12 
 
178 COMPEND OF HUMAN PHYSIOLOGY. 
 
 What is it on the right side? Around the sub-clavian 
 artery. 
 
 To what is it distributed? All the muscles of the larynx 
 except the crico-thyroid muscle. 
 
 With what does it communicate? With the external 
 laryngeal and the sympathetic nerves. 
 
 Result if cut in young animals? Death. 
 
 Why? The cartilages are soft and collapse. 
 
 What if cut in adult animals ? They border on suffoca- 
 tion. 
 
 What is the nerve of voice? The recurrent laryngeal. 
 
 Where do the filaments come from that cause voice ? 
 From the spinal accessory. 
 
 Proof? Cutting the spinal accessory the inferior laryngeal 
 produces the same effect. 
 
 Does the recurrent laryngeal contain any other motor 
 filaments ? It does. 
 
 Proof? Because if the spinal accessory is cut above, 
 the symptoms are not as bad as cutting the inferior laryn- 
 geal. 
 
 Why does the external laryngeal arise from the superior ? 
 It goes down to the crico-thyroid to prepare the larynx for 
 speaking. 
 
 Why does the recurrent laryngeal go down and wind 
 around the aorta on the left and sub-clavian artery on the 
 right side? To transmit its force from below, up. 
 
 During what act of respiration do we speak ? Expiration. 
 
 Where does the force come from ? From below. 
 
 What is the depressor nerve of the circulation ? Nerve 
 of Cyon and Ludwig. 
 
 What is its origin ? From the superior laryngeal and 
 pneumogastric. 
 
 To what is it distributed ? To the heart. 
 
 What effect has cutting it on the heart's action ? None. 
 
PNEUMOGASTRIC. 1 79 
 
 What if electricity is applied to the peripheral cut end ? 
 No effect. 
 
 To central end? It reduces the pulsation. 
 
 What effect has cutting of the nerve on arterial pressure ? 
 None. 
 
 If the central end is stimulated, what is the result ? Re- 
 duces arterial pressure. 
 
 What effect if the depressor nerve is stimulated after 
 the great splanchnic has been cut ? It is diminished, but 
 not as much as when the splanchnic is intact. 
 
 What is the fifth branch of the pneumogastrie ? Cardiac 
 branches. 
 
 What do they form ? Cardiac plexus. 
 
 They supply what organ ? The heart. 
 
 How is the heart affected by cutting the cardiac branches 
 of the pneumogastrie ? It beats faster. 
 
 What will it do if the pneumogastrie is cut ? It beats 
 faster. 
 
 What if upper root of spinal accessory? It beats 
 faster. 
 
 From what nerve does the inhibitory action of the pneu- 
 mogastrie come ? The spinal accessory. 
 
 What is the sixth branch of the pneumogastrie ? The 
 pulmonary branches. 
 
 What forms the anterior pulmonary plexus ? The ante- 
 rior pulmonary branches of the pneumogastrie and branches 
 from the cardiac plexus. 
 
 What forms the posterior pulmonary plexus ? Posterior 
 pulmonary branches, and branches from the third and fourth 
 thoracic ganglia. 
 
 What is the effect of cutting the pulmonary branches ? 
 The lung becomes carnified. 
 
 Name the seventh branch of the pneumogastrie ? Oeso- 
 phageal. 
 
l8o COMPEND OF HUMAN PHYSIOLOGY. 
 
 What are the symptoms if it is cut? Paralysis of the 
 lower part of the oesophagus. 
 
 What are the last branches of the pneumogastric ? 
 Gastric. 
 
 What are the symptoms about the stomach if the pneu- 
 mogastric is cut? Secretion is arrested and the walls are 
 paralyzed. 
 
 Why are the walls paralyzed ? Because the motor nerve 
 of the stomach gets there through the pneumogastric. 
 
 Is the pneumogastric nerve the motor nerve to the 
 stomach ? No. 
 
 What is the source of the motor nerve of the stomach ? 
 From the sympathetic. 
 
 How does it get there ? Through the pneumogastric. 
 
 What is the inhibitory nerve to the blood-vessels of the 
 stomach? The pneumogastric. 
 
 What effect has cutting it ? The blood vessels contract. 
 
 What effect if it is stimulated ? The blood vessels dilate. 
 
 What if the sympathetic is cut ? Dilates them. 
 
 What if the sympathetic is stimulated ? They contract. 
 
 What are the symptoms in the bowels if the pneumo- 
 gastric is cut ? Loss of motion 
 
 How are the blood-vessels influenced ? They contract. 
 
 How are they influenced if it be stimulated ? They 
 dilate. 
 
 If the pneumogastric is cut between the lungs and liver, 
 how is the glycogenic function of the liver influenced ? It 
 is not affected. 
 
 What if the pneumogastric is cut in the neck ? Its func- 
 tion is arrested. 
 
 What is the effect of injury of the floor of the fourth 
 ventricle of the brain? Causes diabetes mellitus. 
 
 In clap, why is tjiere pain in the rectum ? Branches ot 
 the internal pudic nerve supply both parts. 
 
PXEUMOGASTRIC. l8l 
 
 Why on the tuber ischii ? The inferior pudendal nerve is 
 affected. 
 
 After operation for piles, why is there pain in the head of 
 the penis? Both parts are supplied by the internal pudic nerve. 
 
 Where is the pain in cystitis ? At the neck of the bladder. 
 
 In irritation of the neck of the bladder, where is the 
 pain ? In the head of the penis. 
 
 Why ? Inj ury of the sacral nerves, which suppty both parts. 
 
 When a nerve is injured, where is the pain expressed ? 
 At its distribution. 
 
 In hip-joint disease, why is there pain at the knee ? The 
 obturator nerve supplies both parts. 
 
 In pleuritis, why have pain on the inside of the arm ? 
 The intercosto humeral nerve communicates with the nerve 
 of Wrisberg. 
 
 In inflammation of the diaphragm, where is the pain ? 
 Over the clavicle, sternum and acromium process. 
 
 Why ? Due to communication of the phrenic nerve with 
 the cervical plexus. 
 
 If there is pain on the back part of the ear or immedi- 
 ately in back of it, where is the injury? In the neck, in- 
 volving the cervical plexus. 
 
 Give the rationale of a blister and plaster ? They relieve 
 tension by dilating the capillaries, giving better blood supply. 
 
 Why is the glutens maximus muscle supplied by the les- 
 ser ischiatic nerve ? So that in sexual intercourse that mus- 
 cle will act in unison at the crisis or termination of the act 
 of copulation. 
 
 Why does the spinal accessory nerve go through the 
 cranium ? To become the nerve of voice. 
 
 In disease of the liver, where is the pain ? At the lower 
 part of the scapula. 
 
 Why ? The great splanchnic nerve is involved, supplying 
 both parts. 
 
1 82 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XXXIX. 
 
 SPINAL CORD. 
 
 What is the cerebrospinal axis ? Ans. The nervous 
 
 matter in the cranium and spinal canal exclusive of the 
 cranial and spinal nerves. 
 
 What membranes surround it? Dura mater, arachnoid 
 and pia-mater. 
 
 What is the relation of the fluid to the axis? It sur- 
 rounds it. 
 
 Where is the gray matter in the brain ? On the outside'. 
 
 Where is it in the cord ? On the inside. 
 
 What kind of membrane is the dura mater? Fibro serous. 
 
 How many flbro-serous membranes in the body ? Three. 
 
 Name them ? Pericardium, dura mater and tunica albu- 
 ginea. 
 
 Give its physiological anatomy ? Dense fibrous inelastic 
 membrane. 
 
 Where is it attached to the bone ? In the cranial cavity 
 and at the foramen magnum. 
 
 Give its peculiarity in the spinal canal? Hangs loosely 
 around the cord. 
 
 Describe the arachnoid ? A delicate serous membrane 
 with the surfaces almost in contact. 
 
 Where is the fluid ? Beneath both layers. 
 
 Name the fluid? Cephalo-raehidian fluid. 
 
 Describe the pia-mater ? A delicate fibrous membrane 
 which is very vascular. 
 
 What is its function? To give nutrition to the brain and 
 cord. 
 
 How does it differ around the cord? Thicker, stronger, 
 less vascular and more closely adherent. 
 
 What is it somtime3 called ? The neurilemma of the cord. 
 
SPINAL CORD. 183 
 
 What forms the sheath of spinal nerves ? The pia-mater. 
 
 What is its arrangement around the cord ? It is in bands. 
 
 What is the ligamentum denticulatum ? A narrow band 
 between the anterior and posterior roots of the spinal nerves 
 extending from the foramen magnum to the filum terminate. 
 
 Is the quantity of blood in the brain subject to variation 
 in health and disease ? Yes. 
 
 During what act of respiration is the volume of the en- 
 cephalon greatest? Expiration. 
 
 Why ? It favors arterial flow and retards venous. 
 
 When does it decrease ? During inspiration. 
 
 Why ? Inspiration increases venous and retards arterial 
 circulation. 
 
 Give the peculiarity of the encephalic capillaries ? They 
 are surrounded by a perivascular system and lymphatics. 
 
 Why? To equalize the pressure. 
 
 Name the fluid of the brain and cord ? Cephalo-rachidian 
 fluid. 
 
 Where is the greatest amount situated ? In the sub- 
 arachnoid space. 
 
 How do the ventricles of the brain communicate with 
 the central canal? At the floor of the fourth ventricle. 
 
 How much of the fluid is there ? About two fluid ounces. 
 
 What are the symptoms if it be drawn out forcibly with 
 a syringe ? The movements are at first impeded and finally 
 have paralysis. 
 
 Why ? You have a congestion of blood-vessels, followed 
 by effusion. 
 
 What if there is a sudden increase of the fluid ? Coma. 
 
 Why? It compresses the centers. 
 
 Give the properties of the cephalo - rachidian fluid ? 
 Transparent, colorless, non-viscid alkaline fluid of a saline 
 taste, and it resists putrefaction for a long time. 
 
 What is its function? To equalize blood pressure. 
 
I84 COMPKND OF HUMAN PHYSIOLOGY. 
 
 Where do you find the spinal cord? In the spinal canal. 
 
 How long is it ? Fifteen to eighteen inches. 
 
 How much does it weigh ? One and one-half ounces. 
 
 What is its extent ? From the foramen magnum to the 
 first lumbar vertebra. 
 
 Name its enlargements ? Medulla oblongata and the 
 brachial and lumbar enlargements. 
 
 What is the filum terminale ? The slender gray termina- 
 tion. 
 
 What is the chorda equina? The sacral and coccygeal 
 nerves which pass downward from their origin. 
 
 Where is the white matter of the cord ? Outside. 
 
 Where is the gray? Inside. 
 
 Where is the proportion of the white to the gray great- 
 est? Above. 
 
 Why? The fibres going to the cord increase it from be- 
 low up. 
 
 Where is the cord wholly gray ? At its inferior extremity. 
 
 Name the fissures ? Anterior and posterior median fissures. 
 
 What is the extent of the anterior ? One-third the thick- 
 ness of the cord. 
 
 What does it receive ? A fold of pia-mater. 
 
 What is the extent of the posterior? One-half the thick- 
 ness of the cord. 
 
 What fills it? Connective tissue and blood-vessels. 
 
 How is the cord divided? Into two lateral halves. 
 
 How is each half divided? Into anterior, posterior and 
 lateral columns. 
 
 Give the boundaries of the anterior column? Anterior 
 median fissure and the motor root of the nerves. 
 
 What bounds the lateral columns ? The anterior and pos- 
 terior roots of the spinal nerves. 
 
 Give them of the posterior column? Posterior median 
 fissure and the posterior root of the nerves. 
 
SPINAL CORD. 185 
 
 What shape is the gray matter of the cord ? Like the 
 letter H. 
 
 Describe the anterior cornua ? Broad and does not come 
 near the surface. 
 
 Describe the posterior ? Narrow and long, and comes 
 near the surface. 
 
 What connects the gray matter? Gray commissure. 
 
 How many gray commissures are there ? Two. 
 
 What is in the center ? Central canal. 
 
 What lines the canal ? Epithelium. 
 
 It communicates above with what ? Fourth ventricle of 
 the brain. 
 
 What surrounds the central canal ? Connective tissue. 
 
 What is the composition of the white matter ? Made up 
 of nerve fibres. 
 
 What cells are found in the anterior gray cornua ? Large 
 multipolar. 
 
 Are they motor or sensory? Motor. 
 
 What cells are in the posterior cornua? Small multi- 
 polar cells. 
 
 What is the function of the cord ? To act as a center and 
 a means of communication between the brain and the ex- 
 tremities. 
 
 Through what part are impressions carried ? Gray mat- 
 ter and posterior roots. 
 
 The force is sent back to the muscles through what part ? 
 The anterior and lateral columns. 
 
 What other function has the cord ? To act as a center. 
 
 What part acts as a center ? The gray matter. 
 
 How does the anterior root of the nerve arise from the 
 large multipolar cells ? The axis- cylinder is continuous 
 with the poles. 
 
 How are the cells connected with the brain? Nerve fila- 
 ments are sent up. 
 
186 COMPKXI) OF Hl'MAN PHYSIOLOGY. 
 
 Through what part do they pass ? Anterior and lateral 
 columns. 
 
 Does the posterior root of the nerve arise from the cell ? 
 No. 
 
 From what does it arise? From number of nerve fila- 
 ments coining from the cell. 
 
 In what way are the small multipolar cells connected 
 with the brain? Nerve filaments are sent up. 
 
 Through what part do they pass ? Gray matter. 
 
 What parts of the cord are excitable? Anterior and lat- 
 eral white columns. 
 
 What is meant by excitable ? When stimulated it causes 
 motion. 
 
 Is this part sensitive ? No. 
 
 What part is sensitive ? Posterior column. 
 
 Where is it most sensitive ? Near the root of the nerve. 
 
 Is this part excitable ? No. 
 
 Is the gray matter excitable and sensible ? No. 
 
 What is the function of the anterior and lateral columns ? 
 To transmit motor nerves. 
 
 Proof? Cut them and it will cause loss of motion below. 
 
 What are the symptoms if the lateral columns in the 
 cervical region are cut ? Paralysis of motion on the side 
 cut. 
 
 If the anterior columns are cut? Only diminished mo- 
 tion. 
 
 If cut lateral column in the dorsal region ? Diminished 
 motion on the same side. 
 
 If cut anterior column in the dorsal region ? Loss of 
 motion below. 
 
 What is hemiplegia? Paralysis of one side of the body. 
 
 The fibres from the right side of the brain pass to which 
 side of the cord ? To the left side. 
 
 Where do they cross over? In the medulla oblongata. 
 
SPINAL CORD. 187 
 
 What is paraplegia ? Paralysis of the body from the 
 thigh down. 
 
 What is the function of the gray matter of the cord ? To 
 act as a center. 
 
 Proofs Sever the head from the body, you still have mo- 
 tion. 
 
 Where do the sensory filaments decussate ? In the gray 
 matter all up and down the cord. 
 
 Proof? Split the cord from the anterior to posterior me- 
 dian fissure, it causes loss of sensation on both sides. 
 
 What is the function of the posterior columns of the 
 cord? To preside over muscular co-ordination. 
 
 Proof? Cutting it causes locomotor ataxia. 
 
 What is tabes dorsalis? Loss of muscular co-ordina- 
 tion. 
 
 What are the symptoms of cutting half the cord in the 
 cervical region ? Loss of motion and hyperesthesia on the 
 same side and loss of sensation on the opposite side. 
 
 If cut in the dorsal region ? Same as in the cervical. 
 
 Where is the loss of motion ? On the same side. 
 
 The loss of sensation ? On the opposite side. 
 
 Where is the hypersesthesia ? On the same side that is 
 cut. 
 
 How is sensation affected by cutting the gray matter 
 from the medulla to the lower portion in a vertical direc- 
 tion ? It is lost on both sides. 
 
 How is motion affected ? It is not affected. 
 
 How is motion affected by cutting vertically between the 
 two anterior pyramids of the medulla oblongata ? It is 
 lost on both sides below. 
 
 How is sensation affected ? It is not affected. 
 
 What effect has decapitation on sensation ? Lost. 
 
 Why ? The brain only appreciates pain. 
 
 What effect has it on voluntary motion ? It is lost. 
 
1 88 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Why ? The brain is absent. 
 
 Does it destroy the function of the motor and sensory 
 nerves? No. 
 
 What part of the nervous system generates force ? The 
 cells. 
 
 Does severing the head from the body destroy motion ? 
 No. 
 
 What is this motion called? Reflex motion. 
 
 Are reflex movements confined to the cord ? No. 
 
 Give illustration ? The movements of the iris are reflex 
 and are confined to the brain. 
 
 What kind of movement do we mean when we say re- 
 flex? Its cause originates on the surface and it is involun- 
 tary. 
 
 What conditions are necessary for movements to take 
 place in a frog after decapitation ? An irritant must be ap- 
 plied to the surface. 
 
 What condition is necessary for reflex movements to 
 take place from the cord ? The roots of one or more of the 
 nerves must be intact. 
 
 Under what conditions will movements take place when 
 all the nerves have been severed but one ? There must be a 
 great stimulus. 
 
 What effect has decapitation on reflex excitability ? It 
 increases it. 
 
 How is the lower part of the cord affected by section in 
 the dorsal region ? Its reflex action is increased. 
 
 What effect have opium and strychnine poisoning? 
 The}- increase it. 
 
 What effect have anaesthetics ? They diminish it. 
 
 How can you tell complete anaesthesia? The reflex of 
 the eye is lost. 
 
 What is the effect of irritating the soles of the feet in 
 paraplegia ? It causes motion of the legs. 
 
BRAIN. 189 
 
 On what do the movements of deglutition depend ? On 
 reflex action. 
 
 On what does the ejaculation of semen depend? Reflex 
 action also. 
 
 Give an illustration of reflex action of the sympathetic 
 system? The action of the bowels or defecation. 
 
 CHAPTER XL. 
 
 BRAIN. 
 
 What is"the function of the gray matter ? Ans. To gen- 
 erate force. 
 
 How are the impressions carried to the brain ? Through 
 the gray matter in the cord and the cranial nerves. 
 
 Does the brain have to do with reflex action? Yes. 
 
 Illustrate ? Contraction of the iris is reflex. 
 
 "What is the weight of the brain in the male? Forty- 
 eight to fifty-two ounces. 
 
 How much in the female? Forty-three to forty-seven 
 ounces. 
 
 How much did the largest brain weigh ? Seventy-two 
 ounces. 
 
 Give its weight at birth ? Ten to eleven ounces. 
 
 Give the rapidity of development at different periods? 
 It increases to fort)', then it decreases. 
 
 What is the proportion of the size of the cerebrum com- 
 pared to the cerebellum in the male ? It is eight and four- 
 seventh times larger. 
 
 How in female ? Eight and one-fourth times larger. 
 
 What is the appearance of the surface of the cerebrum ? 
 It is convoluted. 
 
190 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Where is the gray matter? On the outside. 
 
 How thick is it in a convolution ? One-twelfth to one- 
 eighth inch. 
 
 Where are the sensory cells ? On the surface. 
 
 Where are the motor cells ? Deeper. 
 
 Is the brain excitable ? No. 
 
 Is it sensitive ? No. 
 
 Exception^ Some of the ganglia. 
 
 What is the function of the cerebrum? To preside over 
 intellect. 
 
 What effect has extirpation on hearing, sight and smell ? 
 They are slightly blunted. 
 
 Effect on sensation and motion? None. 
 
 If the brain is destroyed, is it reproduced ? No. 
 
 What are the symptoms of hemorrhage in the corpus 
 striatum? Have loss of motion on the other side. 
 
 Does the brain weigh more in man or inferior animals ? 
 In man. 
 
 Exception? The brain of the elephant and the whale. 
 
 What is the proportion of the size of the cerebrum in 
 man and inferior animals ? It is larger in man. 
 
 What appearance has the surface of the brain in inferior 
 animals? It is smooth. 
 
 What is the relation of the number and depth of the 
 convolutions to the intellect ? Direct. 
 
 The development of the cerebrum in different races of 
 men is in what proportion? To the degree of civilization. 
 
 What is the relation of the size of the brain to the intel- 
 lect? Usually direct. 
 
 Is the rule absolute ? No. 
 
 Give an exception? The largest brain on record was that 
 of an idiot. 
 
 What has exercise to do with the development of the 
 brain ? The development depends on exercise. 
 
CEREBELLUM. 191 
 
 What faculty has been located in the brain ? The power 
 to articulate language. 
 
 Where is it located? In the third convolution of the an- 
 terior lobe of the left hemisphere. 
 
 Proof? If destroyed, speech is usually lost. 
 
 Is its location definite ? Xo. 
 
 Why? Because when the supposed location is injured you 
 sometimes have speech, and injury to other parts sometimes 
 causes the loss of speech. 
 
 CHAPTER XLI. 
 
 CEREBELLUM. 
 
 What is its color on the surface ? Ans. Gray. 
 
 Internally ? White. 
 
 Describe the superior peduncle ? It connects the cere- 
 bellum with the cerebrum. 
 
 Describe the middle peduncle ? It connects the two hem- 
 ispheres of the cerebellum. 
 
 Describe the inferior? It connects the cerebellum with 
 the corpora restiformia. 
 
 How are the sides of the cerebellum connected ? By the 
 middle peduncle. 
 
 Give the properties of the cerebellum ? Neither excita- 
 ble nor sensible. 
 
 What is its function? To preside over muscular co-ordi- 
 nation and reproduction. 
 
 What is the function of the corpora striata ? The}' have 
 to do with motion. 
 
 What is the function of the thalami optici ? They have 
 to do with sensation. 
 
I92 COMPEND OF HUMAN PHYSIOLOGY. 
 
 Function of the corpora quadrigemina ? Has to do with 
 sight. 
 
 Give the properties of the pons Varolii ? Excitable and 
 sensible on its posterior part. 
 
 What is its other name ? Tuber annulare. 
 
 What is its general function ? Has to do with motion and 
 sensation. 
 
 Does it act as a nerve center ? Yes. 
 
 Proof? If the cerebrum is removed, can still have motion. 
 
 CHAPTER XUI. 
 
 MEDULLA OBLONGATA. 
 
 What is it? Ans. The upper dilated portion of the spinal 
 cord. 
 
 How long is it ? One and one-half inches. 
 
 How wide? Three-fourths to one inch. 
 
 What is its position ? On the basilar process of the occip- 
 ital bone. 
 
 How is it divided ? Into two halves. 
 
 Name the fissures? Anterior and posterior median fis- 
 sures. 
 
 With what are the anterior pyramids continuous ? The 
 lateral and anterior white columns of the cord. 
 
 Where do the nerves decussate ? In the median line. 
 
 Where are the corpora olivaria ? External to the corpora 
 pyramidale. 
 
 What shape are they ? Oblong. 
 
 What surrounds them ? A groove. 
 
 What color are they on the surface? White. 
 
 On the interior ? Gray. 
 
SPECIAL SENSE. 193 
 
 Where are the restiform bodies ? External to the olivary 
 bodies. 
 
 With what are they continuous ? Posterior white column 
 of the cord. 
 
 Where is the lateral tract ? Beneath the olivary bod}- be- 
 tween the corpus pyramidale and restiformia. 
 
 Where is the respiratory center? In the lateral tract. 
 
 What is the function of the medulla ? Has to do with 
 reflex action, respiration, heart's action and deglutition. 
 
 CHAPTER XLHI. 
 
 SPECIAL SENSE. 
 
 Give the origin of the olfactory nerve ? Ans. By three 
 roots, one from the carunculae mammi Hares in the anterior 
 lobe, the inner from the anterior lobe near the substantia 
 perforata, and the external from the anterior commissure in 
 the third ventricle. 
 
 Give its distribution? The mucous membrane of the 
 nose. 
 
 Give its properties ? It is a nerve of special sense. 
 
 Its function? To give to the nose the sense of smell. 
 
 Name the nerves of taste ? Chorda tympani and glosso- 
 pharyngeal. 
 
 What is the origin of the chorda tympani ? From the 
 facial. 
 
 To what part of the tongue is it distributed ? Anterior 
 part. 
 
 What is the origin of the glossopharyngeal ? Between 
 the corpus olivary and restiformia. 
 
 What are its properties at its origin ? Special sense. 
 13 
 
194 COMPEND OF HUMAN PHYSIOLOGY. 
 
 At its distribution ? Mixed. 
 
 What is its function ? Give taste to the back part of the 
 tongue. 
 
 Give the mechanism of taste? Food comes in contact 
 with the terminal filaments of the nerves of taste, which carry 
 the impression to the brain. 
 
 What is the origin of the optic nerve ? Corpus genicula- 
 tum externum, thalamus opticus, brachium anterius and 
 nates. 
 
 Distribution? To the retina of the eye. 
 
 What kind of nerve is it? Nerve of special sense. 
 
 What is its function? To give to the eye the sense of 
 sight. 
 
 CHAPTER XLIV. 
 
 SYMPATHETIC. 
 
 What does it mean ? Suffering for another. 
 
 What other names has this system ? Ganglionic or vege- 
 tative system. 
 
 What is its arrangement? In a double chain, up and 
 down the vertebral column. 
 
 To what is it distributed ? Non-striated muscular fibres. 
 
 Give the exception ? It is distributed to the heart. 
 
 What is the color of a sympathetic nerve? Gray or 
 red. 
 
 What is peculiar about its fibres ? They are smaller than 
 other fibres. 
 
 What is peculiar of the cells? They are mostly bipolar. 
 
 Are they motor and sensory ? They are motor. 
 
 Proof of each? Can have motion or pain by stimulating 
 them. 
 
SYMPATHETIC. 195 
 
 How does the motion differ from that of the cerebro- 
 spinal system ? It comes on slower and is less powerful. 
 
 What is the origin of the action of the sympathetic ? 
 From the cerebro-spinal. 
 
 What regulates the pupil of the eye ? The cerebro-spinal 
 and sympathetic nerves. 
 
 All the motor fibres come from what ganglion ? Oph- 
 thalmic. 
 
 What is meant when the term vaso-motor is used ? Mo- 
 tion to the vessel. 
 
 What are the symptoms if the superior cervical ganglion 
 is destroyed ? An increased blood supply to that side of the 
 head. 
 
 What is the origin of part of its power ? From the cer- 
 vical ganglia below. 
 
 What is the origin of the vaso-motor fibres of the neck ? 
 The spinal cord. 
 
 How is it connected with the sympathetic ? Each 
 ganglion sends communicating branches to the spinal 
 nerves. 
 
 What are the symptoms if the first and second dorsal 
 nerves are cut in the spinal canal ? The blood vessels on 
 that side become dilated. 
 
 What if the trunk of the sympathetic is cut between the 
 second and third ribs? They become still more dilated. 
 
 From where do the sensory and motor nerves of the 
 head and face come ? Cranial nerves. 
 
 Where do the nerves to the blood-vessels come from ? 
 From the spinal cord below. 
 
 Proof? If the second and third dorsal nerves are cut be- 
 fore they get out of the spinal canal, the blood-vessels of the 
 head and face become widely dilated. 
 
 What is the origin of the motor and sensory nerves of 
 the arm? From the brachial plexus. 
 
196 COMPEXD OF HUMAN PHYSIOLOGY. 
 
 What is the origin of the nerves to the blood vessels of 
 this part ? From the cord as low down as the fourth and fifth 
 dorsal nerves. 
 
 Proof? If the nerves forming the brachial plexus are cut 
 before the}* get out of the spinal canal, there is loss of mo- 
 tion and sensation in the arm, but if the cord is injured as 
 low as the fourth and fifth dorsal nerves, the blood supply to 
 the arm is increased. 
 
 What is the origin of the motor and sensory nerves of 
 the lower leg ? From the sacral plexus. 
 
 What is the origin of the nerves of the blood-vessels to 
 this part? From the cord higher up. 
 
 Proof? By cutting the nerves forming the sacral plexus 
 there is loss of motion and sensation in the leg, while cutting 
 the nerves higher up the blood supply to the part is increased. 
 
 What are the symptoms if the vaso-motor or sympathetic 
 nerves to the blood-vessels of the salivary glands are cut ? 
 The vessels dilate. 
 
 Effect of cutting the sympathetic in the neck? The 
 blood-vessels of the neck become dilated. 
 
 Effect of cutting the sympathetic nerves going to the 
 heart ? It beats slower. 
 
 If cut those going to the stomach ? It increases digestion. 
 
 If cut the great splanchnic nerve ? The blood vessels of 
 the guts become dilated. 
 
 What are the nerves that cause dilatation of the blood- 
 vessels ? Vaso-motor dilators. 
 
 What is their origin? From the cerebro-spinal system. 
 
 What is the dilator nerve of the blood-vessels of the sal- 
 ivary glands? The chorda tympani nerve. 
 
 Of the heart ? The pneumogastric nerve. 
 
 Of the blood vessels of the stomach ? The pneumogastric. 
 
 What are the symptoms if it is cut ? Have diminished 
 blood supply and loss of motion. 
 
SYMPATHETIC. 197 
 
 Nerves from what systems are distributed to blood-vessels 
 of the stomach? Cerebro-spinal and sympathetic. 
 
 What are the symptoms if the cerebro-spinal is cut? 
 The blood-vessels contract. 
 
 What if it is stimulated ? They dilate. 
 
 What are the symptoms if the sympathetic is cut ? The 
 blood-vessels dilate. 
 
 What if the dilator or inhibitory nerve is cut ? They con- 
 tract. 
 
 If it is stimulated, what effect ? They dilate. 
 
 What does the inhibitory counteract when stimulated ? 
 The sympathetic. 
 
 What causes the vessels to dilate ? The pressure of the 
 blood in the arteries. 
 
 Explain the action of the nerves on sphincter muscles ? 
 When the sympathetic is stimulated it narrows the opening, 
 as it causes contraction of the circular fibres. 
 
 Explain the reflex dilatation of blood-vessels ? When 
 food is taken in the mouth the sensory nerves receive the 
 impression and carry it to the center, which sends out force 
 to the blood-vessels of the salivary glands and causes them 
 to dilate. 
 
98 COMPEND OF HUMAN PHYSIOLOGY 
 
 CHAPTER XLV. 
 
 REPRODUCTION. 
 
 What is reproduction ? Ans. Reproduction is the func- 
 tion by which the species is preserved, and is accomplished 
 by the organs of generation in the two sexes. 
 
 As regards physiology, what can you say of the so-called 
 spontaneous generation ? Formerly this question was much 
 discussed, especially in relation to some of the lower ani- 
 mals ; this, however, is now of purely historical interest. As 
 actual knowledge of facts have accumulated, the limits of 
 what was thought to be spontaneous generation have become 
 more and more restricted, until now it is generally admitted 
 that it does not exist in the histor) T of animals. 
 
 Give a certain distinct form of generation ? There are 
 other certain distinct forms of generation, but the only one 
 that has any considerable importance in connection with hu- 
 man physiology is generation of new beings by the union 
 of male and female elements in the fecundation of the ovum, 
 with the development of the fecundated ovum. 
 
 This is known as what? Known as sexual generation. 
 The two elements of generation are developed in separate 
 beings, male and female, and those elements are brought to- 
 gether normally, in what is known as sexual connection or 
 copulation. 
 
FEMALE ORGANS OF GENERATION. 199 
 
 CHAPTER XT.VI. 
 
 FEMALE ORGANS OF GENERATION. 
 
 What is most important for a comprehension of those 
 special organs of generation ? Ans. A knowledge of cer- 
 tain points in the anatomy is essential to the comprehension 
 of the most important of the process of generation. 
 
 As regards the functions of generation, to what extent 
 does nature depend upon the male, following a fruitful in- 
 tercourse of the sexes ? Following a fruitful intercourse, as 
 regards the male, ceases with the comparatively simple pro- 
 cess of penetration of the male element through the protective 
 covering of the ovum and its fusion with the female element. 
 
 After the two element come in contact, what follows ? 
 The fecundated ovum then passes through certain changes, 
 which are the first process of its development, forms its at- 
 tachments to the bod)- of its mother, continues its develop- 
 ment and is nourished and grows until the foetus at term is 
 brought into the world. 
 
 How are the female organs of generation divided? 
 Anatomically, into external and internal ; thus, the external 
 organs are the vulva, adjacent parts, and the vagina. The 
 internal are the uterus, the Fallopian tubes and the ovaries. 
 
 What is most important ? The ovaries are the true fe- 
 male organs of generation, in which alone the female ele- 
 ment can be produced, although the Fallopian tubes and 
 the uterus are accessory in their use, the ovum passing 
 through the Fallopian tubes to the uterus, where it forms at- 
 tachments to the body of the mother, which are essential to 
 its nourishment and full development after fecundation. 
 
 Please give the anatomy in detail of the female organs 
 of generation? The ovaries are two small ovoid, flattened 
 bodies, measuring one inch and a half in length by three- 
 
200 COMPEND OF HUMAN PHYSIOLOGY. 
 
 quarters of an inch in width. They are situated in the cav- 
 ity of the pelvis and imbedded in the posterior layer of the 
 brood ligaments, and attached to the uterus by a round liga- 
 ment. The ovary consist of an external membrane of fibrous 
 tissue, the cortical portion, in which are imbedded the 
 Graafian vesicles and the internal portion. The stroma con- 
 tains blood-vessels. The weight of each ovary is from sixty 
 to one hundred grains (3-9 to 6-5 grammes), and these organs 
 are largest in the adult virgin. Its attached border is called 
 hilum, and at this portion the vessels and nerves penetrate, 
 and its surface is marked by rounded, translucent elevations, 
 produced by distended Graafian follicles, with little cicatrices 
 indicating the situation of ruptured follicles. 
 
 Graafian Follicles. — These vesicles or follicles were 
 described and figured by Dr. Graafe in 1672, and are known 
 by his name. They are exceedingly numerous, but situated 
 only in the cortical portion. Although the ovary contains 
 the vesicles from the period of birth, it is only at the period 
 of puberty that the)' attain their full development. From 
 this time onward to the catamenial period there is a con- 
 stant growth and maturation of the Graafian follicles. 
 The\' consist of an external investment, composed of fibrous 
 tissue and blood-vessels, in the interior of which is a layer 
 of cells forming the membrana granulosa. At its lower por- 
 tion there is an accumulation of cells, the proligcrous disc, 
 in which the ovum is contained. The cavity of the vesicle 
 contains a slightly yellowish alkaline, albuminous fluid. In 
 the process which culminates in the discharge of the ovum 
 into the fimbriated extremity of the Fallopian tube, the 
 Graafian follicle gradually enlarges, becomes distended with 
 liquid and finally breaks through and ruptures upon the sur- 
 face of the ovary. 
 
 The Parovarium. — The Parovarium or organ of Rosen- 
 muller is simply the remains of the Wolffian body, lying in 
 
FEMALE ORGANS OF GENERATION. 201 
 
 the folds of the broad ligaments, between the ovary and the 
 Fallopian tube. It consists of twelve to fifteen tubes of 
 fibrous tissue, lined by ciliated epithelium. It has no physio- 
 logical importance. 
 
 The Uterus. — The uterus is a pear-shaped body, some- 
 what flattened antero-posteriorly, presenting a fundus, a 
 body and a neck. 
 
 At its lowest extremity is an opening into the vagina, 
 called the os-externum. At the upper portion of the neck is 
 a constriction which indicates the situation of the os-inter- 
 num. The uterus is usually about three or three and a 
 half inches long, two inches in breadth at its widest portion, 
 and one inch in thickness. Its weight is from one and a half 
 to two and a half ounces (42-5 to 71 grammes). It is some- 
 what loosely held in place by the broad and round ligaments 
 and by the folds of the peritoneum in front and behind the 
 delicate layer of peritoneum which from its outer covering 
 extends behind as far down as the vagina, where it is reflect- 
 ed back upon the rectum, and anteriorly, a little below the 
 upper extremity of the neck (os internum), where it is re- 
 flected upon the urinary bladder. 
 
 The muscular walls of the uterus are composed of non- 
 striated fibrous tissue arranged in several layers. They are 
 so closely bound together that they are isolated with great 
 difficulty, and the muscular tissue of the uterus is remark- 
 able from the fact that the fibres enlarge immensely during 
 gestation, becoming at that time ten or fifteen times as long, 
 and five to seven times as broad as they are in the unimpreg- 
 nated state. 
 
 The mucous membrane of the uterus is of a pale, reddish 
 color, and that portion lining the body is smooth, and is so 
 closely attached to the subjacent structures that it can not 
 be separated to any great extent by dissection. 
 
 The changes which the mucous membrane of the uterus 
 
202 COMPEND OF HUMAN PHYSIOLOGY. 
 
 undergoes during menstruation are remarkable. Under or- 
 dinary circumstances its thickness is one-twenty-fifth to one- 
 fourteenth of an inch, but it measures during the menstrual 
 period one-sixth to one-fourth of an inch. 
 
 The blood-Yessels of the uterus are Yen- large and present 
 certain important peculiarities in their arrangement. The 
 uteririe arteries pass between the layers of the broad ligament 
 to the neck, and then ascend by the sides of the uterus, pre- 
 senting a rich plexus of vessels, anastomosing aboYe with 
 branches from the ovarian arteries, sending branches over 
 the body of the uterus, and finally penetrating the organ, to 
 be distributed mainly in the middle layer of muscular fibres. 
 In their course these vessels present a convoluted arrange- 
 ment and form a sort of mold of the body of uterus. 
 
 In the muscular walls of the uterus are large veins, the 
 walls of which are closely adherent to the uterine tissue. 
 During gestation these vessels become enlarged, forming the 
 so-called uterine sinuses. 
 
 Lymphatics are not very abundant in the unimpregnated 
 uterus, but they become largely developed during gestation. 
 
 The uterine nerves are derived from the inferior hypogas- 
 tric and the spermatic plexus, also the third and fourth sa- 
 cral. In the substance of the uterus they present in their 
 course small collections of ganglionic cells, and it is said that 
 the nerves pass finally to the nucleoli of the muscular fibres. 
 
 The Fallopian Tubes— Are about four inches in length 
 and extend outward from the upper angles of the uterus, be- 
 tween the folds of the broad ligaments, and terminate in a 
 fringed extremity, which is attached by one of the fringes to 
 the ovary. They consist of three coats, (i) the external or 
 peritoneal, (2) middle or muscular, the fibres of which are 
 arranged in a circular or longitudinal direction, (3) internal 
 or mucous, covered with ciliated epithelial cells, which are 
 always waving in a kind of antiperistaltic action from the 
 
FEMALE ORGANS OF GENERATION. 203 
 
 ovary to the uterus, and opening into the uterus upon either 
 side at the eornua. They present a small orifice about one- 
 twenty-fifth of an inch in diameter. From the eornua 
 they take a somewhat undulatory course outward, grad- 
 ually increasing in size, so that the3 r are rather trumpet- 
 shaped. 
 
 The extremity next to the ovary is marked by ten or fifteen 
 fimbriae or fringes, which have given this portion the name 
 of the fimbriated extremity or morsus diaboli. All of these 
 fringe-like processes are free except one, and this one, which 
 is longer than the others, is attached to the outer angle of 
 the ovary, and presents a little gutter or furrow, extending 
 from the ovary to the opening of the tube. At this extrem- 
 ity is the abdominal opening of the tube, which is two or 
 three times as large as the uterine opening. Passing from 
 the uterus, the caliber of the tube gradually increases, as the 
 tube itself enlarges, and there is an abrupt constriction at the 
 abdominal opening. 
 
 External Organs of the FemaeE. — It is not necessary 
 to give a minute description of the female external organs of 
 generation. The opening by the vulva externally, and ter- 
 minating at the neck of the uterus, is a membraneous tube, 
 the vagina. This lies between the bladder and the rectum. 
 It has a curved direction, being three and one-sixth to three 
 and one-half inches (eight to nine centimeters) long in front, 
 and three and one-half to four inches (nine to ten centi- 
 meters) long posteriorly (Sappey), At the constricted por- 
 tion of the outer opening there is a muscle called the sphinc- 
 ter vaginae, and the tube is somewhat narrowed at its upper 
 end, where it embraces the cervix uteri. The inner surface 
 presents a mucous membrane marked by transverse rugae, 
 with papillae and mucous glands. Its surface is covered with 
 flattened epithelium. The vagina is quite extensible, as it 
 must be during parturition, to allow the passage of the child. 
 
204 COMPEND OF HUMAN PHYSIOLOGY. 
 
 The parts composing the external organs are abundantly 
 supplied with vessels and nerves. In the clitoris, which cor- 
 responds to the penis in the male, and on either side of the 
 vestibule, there is a true erectile tissue. 
 
 The Ovum. — The ovum lies in the Graafian follicles im- 
 bedded in the mass of granular cells which form the discus 
 proligerous. Surrounding the ovum are cells similar to those 
 found in the other parts of the membraua granulosa and two 
 or three layers of columnar cells, the latter lying next the 
 zona pellucida. These columnar cells constitute the corona 
 radiata (Bischoff). 
 
 The ovum itself presents the following structures : (i) zona 
 pellucida, (2) perivitelline space, (3) a clear outer zona of the 
 vitellus, (4) protoplasmic zone (formative yelk), (5) dento- 
 plasmic zona (nutritive yelk), (6) germinal vesicle or ger- 
 minal spot. The extremely thin membrane within the zona 
 pellucida and immediately surrounding the vitellus, described 
 under the name of vitelline membrane by some anatomists, 
 was not observed by Nagel in the human ovum. The ovum 
 is globular, with a diameter of about one one-hundred and 
 fiftieth of an inch, measured from the outer border of the 
 zona pellucida. 
 
 As the Graafian vesicle matures, it increases in size, forms 
 an augmentation of its liquid contents and approaches the 
 surface of the ovary, where it forms a projection measuring 
 from one-fourth to one-half an inch in size. The maturation 
 of the vesicle occurs periodically, about every twenty-eight 
 days, and is attended by the phenomena of menstruation. 
 During this period of active congestion of the reproductive 
 organs, the Graafian vesicles rupture, the ovum and liquid 
 contents escape and are caught by the fimbriated extremity 
 of the Fallopian tubes, which has adapted itself to the pos- 
 terior surface of the ovary. The passage of the ovum through 
 the Fallopian tube into the uterus occupies from ten to four- 
 
FEMALE ORGANS OF GENERATION. 205 
 
 teen days, and is accomplished by the muscular contraction 
 and the action of the ciliated epithelium. 
 
 The fact that the ovum in the great majority of instances 
 passes into the Fallopian tubes is sufficiently evident. The 
 fact, also, that ova may fall into the cavity of the peritoneum 
 is illustrated by occasional occurrences of extrauterine preg- 
 nancy, a rare accident, which shows that in all probability 
 the failure of unimpregnated ova to enter the tubes is ex- 
 ceptional. As regards the mechanism of the passage of the 
 ova into the tubes, however, the explanation is difficult. At 
 the present time there are two theories in regard to this 
 process : one, in which it is supposed that the fimbriated ex- 
 tremities of the Fallopian tubes, at the time of rupture of 
 the Graafian follicles, become adapted to the surface of the 
 ovaries, and the other, that the ova are carried to the open- 
 ings of the tubes by ciliary currents. Neither of these the- 
 ories, however, is susceptible of actual demonstration, and 
 their value is to be judged from anatomical facts. 
 
 Puberty and Menstruation. — At a certain period of 
 life, usually between the ages of thirteen and fifteen, the 
 human female undergoes a remarkable change and arrives at 
 what is termed puberty. At this time there is a marked in- 
 crease in the general development of the body ; the limbs 
 become fuller and more rounded, a growth of hair makes its 
 appearance upon the mons veneris, the mammary glands in- 
 crease in size and take on a new stage of development, 
 Graafian follicles enlarge, and one or more approach the con- 
 dition favorable to rupture and discharge of the ova. The 
 female becomes capable of impregnation, and continues so, 
 in the absence of pathological conditions, until the cessation 
 of the menses. 
 
 The age of puberty is earlier in warm than in cold climates, 
 and many instances are on record in which the menses have 
 appeared exceptionally much before the usual period. Gen- 
 
206 COMPEXD OF HUMAN PHYSIOLOGY. 
 
 erally at the age of forty or forty -five the menstrual flow 
 becomes irregular, occasionally losing its sanguineous char- 
 acter, and it usually ceases at about the age of fifty years. 
 In a condition of health the periods recur every month un- 
 til they cease, at what is termed the change of life. In the 
 majority of cases the flow recurs on the twenty -seventh or 
 twenty-eighth day, but sometimes the interval is thirty days. 
 As a rule, also, utero-gestation, lactation and severe dis- 
 eases, acute and chronic, suspend the periods, but this has 
 exceptions, as some females menstruate regularly during 
 pregnancy, and it is not very uncommon for the menses to 
 appear during lactation. 
 
 Removal of the ovaries, especially when this occurs before 
 the age of puberty, usually is followed by the arrest of men- 
 struation. It is a well-known fact that animals do not pre- 
 sent the phenomena of heat after extirpation of the ovaries. 
 Cases have been quoted of this operation in the human sub- 
 ject in which the menses were arrested, but this rule does 
 not appear to be absolute, as other cases have been reported 
 where menstruation continued with regularity for more than 
 a year. 
 
 When a cow gives birth to twins, one a male, the other 
 apparently a female, the latter is called a free-martin and has 
 no ovaries ; it does not breed or show any inclination of the 
 bull. The)- are said to possess a rudimentary uterus, but no 
 ovaries. 
 
 The menstrual period presents three stages : first, invasion ; 
 second, a stage of sanguineous discharge ; third, cessation. 
 
 The stage of invasion is variable in different females. 
 There is usually anterior to the establishment of the flow, 
 more or less of a feeling of general malaise, a sense of fulness 
 and weight in the pelvic organs, accompanied with a greater 
 or less increase in the quantity of vaginal mucus, which be- 
 comes brownish or rusty in color and has a peculiar odor. 
 
GENERATIVE ORGANS OF THE MALE. 207 
 
 At this time, also, the breasts become slightly enlarged. 
 This stage may continue for one or two days, although in 
 many instances the first evidence of the access of a period is 
 a discharge of blood. 
 
 When the symptoms above indicated occur, the general 
 sense of uneasiness usually is relieved by the discharge of 
 blood. During this, the second stage, blood flows from the 
 vagina in variable quantity, and the discharge continues from 
 three to five days. With regard to duration of flow, there 
 are great variations in different individuals. Some women 
 present a flow of blood for only one or two days, while in 
 others the flow continues from five to eight days, within the 
 limits of health. A fair average, perhaps, is four days. 
 
 It is rather difficult to arrive at or even approximate the 
 total quantity of the menstrual flow ; it has been estimated 
 at anywhere from four to twelve ounces. It is well known 
 that the quantity is variable, but an average is not far from 
 five or six ounces. 
 
 CHAPTER XLVII. 
 
 GENERATIVE ORGANS OF THE MALE. 
 
 From a physiological stand-point, as regards the anatomy 
 of the male organs of generation, we are to deal mostly with 
 the testicles, in which, the male element is produced. In 
 relation with the testicles we have vas defer entia, vesicidcs- 
 seminales and penis. 
 
 The Testicles. — The essential organs of reproduction in 
 the male are two symmetrical oblong glands, about one inch 
 and a half long, compressed from side to side and situated 
 during a certain period of intrauterine life in the abdominal 
 cavity, but finally descending into the scrotum. Immedi- 
 
208 COMPKXD OF HUMAN PHYSIOLOGY. 
 
 ately beneath the skin of the scrotum is a loose, reddish, 
 contractile tissue, called the dartos, which forms two dis- 
 tinct sacs, one enveloping each testicle, the inner portion of 
 these sacs fusing in the median line to form the septum. 
 Within this covering the two testicles are distinct and sus- 
 pended in the scrotum by the two spermatic cords, the left 
 usually hanging a little lower than the right. The coverings 
 for the two testicles, in addition to the ones just mentioned, 
 are the inter-columnar fascia, the cremaster muscles, the 
 infundibuliform fascia, the tunica vaginalis and the proper 
 fibrous coat. The tunica vaginalis is a shut sac of serous 
 membrane covering the testicle and epididymis and reflected 
 from the posterior borders of the testicle to the wall of the 
 scrotum, lining the cavity occupied by the testicle on either 
 side and also extending over the spermatic cord. The 
 spermatic cord is composed of the vas deferens, blood-vessels, 
 lymphatics and nerves, with the covering already described, 
 which expand and surround the testicles. 
 
 The proper fibrous coat of the testicles is called the tunica 
 albuginea. It is white, dense, inelastic and measures about 
 one-twenty-fifth of an inch in thickness, and is simply for 
 the protection of the contained structures. 
 
 Sections of the testicles extend in various directions, show 
 an incomplete, vertical process of the tunica albuginea called 
 the corpus Higlimorianum or the mediastinum testis. 
 
 Lining the tunica albuginea and following the mediasti- 
 num and the process which penetrate the testicles is a tunic, 
 composed of blood-vessels and delicate, connective tissue 
 called the tunica vasculosa or pia-mater testis. The substance 
 of the testicles is made up of seminiferous tubules, which ex- 
 ist to the number of eight hundred and forty in each testicle, 
 and constitute almost the entire substance of each lobule. 
 The entire length of these tubules, when unraveled, is about 
 thirtv inches and diameter one one-hundred and seventy- 
 
GENERATIVE ORGANS OF THE MALE. 209 
 
 fifth of an inch. As they pass toward the apices of the lo- 
 bules they become less convoluted and terminate in from twen- 
 ty to thirty straight ducts, the vas recta, which pass upward 
 through the mediastinum and constitute the rete testis. At 
 the upper part of the mediastinum the tubules unite to form 
 from nine to thirty small ducts, the vas affcrentia, which be- 
 come convoluted and form the globus major of the epididymis', 
 the continuation of these tubes downward, behind the testi- 
 cles and a second convolution constitutes the body and globus 
 minor. 
 
 The Vas Deferens. — The excretory duct of the testicles 
 is about two feet in length and extends from the epididymis 
 to the prostatic portion of the urethra, and is a continuation 
 of the single tube which forms the body and globus minor of 
 the epididymis. It is somewhat tortuous near its origin, and 
 it becomes larger at the base of the bladder just before it 
 joins the duct of the seminal vesicle to form the ejaculatory 
 duct. 
 
 The Vesicul.£ Seminales. — Attached to the base of the 
 bladder and situated externally to the vas deferentia are the 
 two vesiculcz seminales. They have an external fibrous coat, a 
 middle muscular coat and an internal mucous coat, covered 
 by epithelium, which secretes a mucous viscid fluid. The 
 vesiculae seminales serve as reservoirs, in which the seminal 
 fluid is temporarily stored up. The ejaculatory duct is about 
 three-fourth of an inch in length, opens into the urethra, and 
 is formed by the union of vas deferentia and the ducts of the 
 vesiculse seminales. 
 
 The Prostate Glands. — This organ, except as it se- 
 cretes a fluid which forms a part of the ejaculatory semen, 
 has chiefly a surgical interest. It is enveloped in a very 
 dense fibrous coat and contains many glandular structures 
 opening into the urethra, and presents a great number of non- 
 striated with a few striated muscular fibres, some just be- 
 14 
 
2IO COMPEND OF HUMAN PHYSIOLOGY. 
 
 neath the fibrous coat and others penetrating its substance 
 and surrounding the glands. 
 
 Glands of Urethra. — In front of the prostates, open- 
 ing into the bulbous portion of the urethra, are two small 
 racemose glands, called the glands of Cowper. These have 
 each a single excretory duct, are lined throughout with cy- 
 lindrical epithelium and secrete a viscid, mucus-like fluid, 
 which forms a part of the ejaculated semen. Sometimes 
 there exists only a single gland, and occasionally, though 
 rarely, both are absent. Their uses are probably not of very 
 much importance. 
 
 Male Elements of Generation. — The spennatozoids 
 are the essential male element of generation, and these are 
 produced in the substance of the testicles, by a process anal- 
 ogous to that of the development of other true anatomical 
 elements. The testicles can not be regarded strictly as 
 glandular organs. Thej^ are analogous to the ovaries, and they 
 are the only organs in which spermatozoids can be developed, 
 as the ovaries are the only organs in which the ovum can 
 be formed. If the testicles be absent the power of fecun- 
 dation is lost, as none of the fluids secreted by accessory 
 organs of generation is able to perform the office of fecun- 
 dation. 
 
 In the health}- male, at the climax of a normal venereal 
 organism, n-6 to 92-6 grains of seminal fluid are ejaculated 
 with considerable force from the urethra by an involuntary 
 muscular spasm. This fluid requires about four days for its 
 full restoration. The spermatozoa are peculiar anatomical 
 elements, developed within the seminal tubules, and possess 
 the power of spontanous movement. The spermatozoa con- 
 sist of a conoidal head and long filamentous tail, which is in 
 continuous and active motion. As long as they remain in 
 the vas deferens thej T are quiescent, but when free to move 
 in the fluid of the vesiculse seminales become very active. 
 
GENERATIVE ORGANS OF THE MALE. 211 
 
 Cold arrests the actions of spermatozoa, but they can be 
 restored by the application of dense saline and other so- 
 lutions. 
 
 As to origin, spermatozoa appears at the age of puberty, 
 and are then constantly forming until an advanced age. 
 They are developed from the nuclei of large round cells con- 
 tained in the anterior of the seminal tubules, as many as 
 fifteen to twenty developing in a single cell. When the 
 spermatozoa are introduced into the vagina the3 T pass readily 
 into the uterus and through the Fallopian tubes toward the 
 ovaries, where the}' remain and retain their vitality for a 
 period of eight to ten days. During the return of the sperm- 
 atozoa with the ovum, fecundation takes place just outside 
 the womb and in the Fallopian tubes. After floating around 
 the ovum in an active manner, they penetrate the vitelline 
 membrane, pass into the interior of the vitellus, where they 
 lose their vitalit3', and along with the germinal vesicle en- 
 tirely disappear. 
 
212 COMPEND OF HUMAN PHYSIOLOGY. 
 
 CHAPTER XLVIII. 
 
 FECUNDATION AND DEVELOPMENT OF THE OVUM. 
 
 So far as the male is concerned, coitns is rendered possible 
 by the erection of the penis. This may occur before puber- 
 ty, but at this time intercourse can not be fruitful. Coitus 
 may be impossible in old age, from absence of power of erec- 
 tion ; but spermatozoids may still exist in the generative 
 organs, and fecundation might occur if the seminal fluid 
 could be discharged into the generative passage of the fe- 
 male. Coitus may take place with the female before puber- 
 ty or after the cessation of the menses, but intercourse can 
 not then be fruitful. 
 
 The spermatozoa once within the cervix uteri, and its fu- 
 sion with the germinal vesicle, there remains a transparent, 
 granular, albuminous substance, in the center of which a 
 new nucleus soon appears. This constitutes the parental 
 cells, and is the first stage in the development of the new 
 being. Following this vitellus undergoes segmentation. A 
 constriction appears on the opposite side of the vitellus, which 
 gradually deepens until the } T elk is divided into two seg- 
 ments, each of which has a distinct nucleus and nucleolus. 
 These two segments undergo a further division into four, the 
 four into eight, the eight into others, and so on until the en- 
 tire vitellus is divided into a great number of cells, each of 
 which contains a nucleus and nucleolus. 
 
 Hereditary Transmission. — As regards the question 
 which determines the sex of offspring, it has been shown 
 that the proportion of male to female births is about 104 to 
 105, these figures, however, presenting certain modifications 
 under varying conditions of climate, season, nutrition, etc.; 
 but nothing has ever been done in the way of procreating 
 male or female children at will. 
 
FECUNDATION AND DEVELOPMENT OF THE OVUM. 213 
 
 Xo definite rule can be laid down with regard to the trans- 
 mission of mental or physical peculiarities to offspring. 
 Sometimes the progeny assumes more the character of the 
 male than of the female parent, and sometimes the reverse is 
 the case without any reference to the sex of the child. 
 Sometimes there appear no such relations, and occasionally 
 peculiarities are observed derived apparently from grand- 
 parents. This is true with regard to pathological as well as 
 physiological peculiarities, as in the inherited tendencies to 
 certain diseases, malformations, etc. 
 
 A peculiar and seemingly inexplicable fact is that previous 
 pregnancies have an influence upon offspring. This is well 
 marked in breeders of animals, but the same influence is fre- 
 quently observed in the human subject. A woman may have 
 by a second husband children who resemble the former hus- 
 band. A white woman may have children by a negro man, 
 and subsequently bear children to a white man, these chil- 
 dren presenting some of the unmistakable peculiarities of the 
 negro race. 
 
 Changes in the Fecundated Ovum. — It is probable 
 that the ovum is fecundated either just as it enters the Fal- 
 lopian tube, or in the dilated portion, near the ovary. As it 
 passes dowm the tube it becomes covered with an albuminous 
 coating. This coating, no doubt, serves to protect the fecun- 
 dated ovum, but finally this albuminous covering liquefies 
 and penetrates the vitelline membrane, furnishing, it is 
 thought, matter for the nourishment and development of the 
 vitellus. 
 
 Primitive Trace. — Soon after the formation of the blas- 
 todermic vesicle, at a certain point there is an accumulation of 
 cells, which marks the position of the future embryo, this 
 spot, first circular, then elongated, and forms the primitive 
 trace, around which is a clear space, the area pellucida, which 
 is itself surrounded by a darker region, the area opaca. The 
 
214 COMPEND OF HUMAN PHYSIOLOGY. 
 
 primitive trace soon disappears, and the area pellucida be- 
 comes elongated ; a new groove, the medullary grooves, is 
 now formed, which develop from before backward, and be- 
 comes the neural canal. 
 
 Blastodermic Layers. — The embryo, at this period, 
 consists of three layers, viz : The external and internal blas- 
 todermic membranes and a middle membrane formed by a 
 genesis of cells from their internal surfaces. These layers 
 are known as the epiblast, the mesoblast and hypoblast. 
 
 The epiblast gives rise to the central nervous system, the 
 epidermis of the skin and its appendages and the primitive 
 kidneys. 
 
 The mesoblast gives rise to the dermis, muscles, bones, 
 nerves, blood vessels, sympathetic nervous system, connective 
 tissue, the urinary and reproductive apparatus and the walls 
 of the alimentary canal. 
 
 The hypoblast gives rise to the epithelial lining of the ali- 
 mentary canal and its glandular appendages, the liver and 
 pancreas, and the epithelium of the respirator} 7 tract. 
 
 Formation of the Membranes.— In the mammalia a 
 portion of the blastoderm is developed into membranes, by 
 which a communication and union is established between 
 the ovum and the mucous membrane of the uterus. From 
 the ovum two membranes are developed ; one non-vascular, 
 the amnion, and another, the allantois, which is vascular. 
 
 The two layers of decidua are formed from the mucous 
 membrane of the uterus. At a certain part of the uterus a 
 vascular connection is established between the mucous mem- 
 brane and the allantois, and the union of these two struct- 
 ures forms the placenta. The foetal portion of the placenta is 
 connected with the foetus by the vessels of the umbilical 
 cord, and the maternal portion is connected with the great 
 uterine sinuses. 
 
 The Amnion. — The amnion appears shortly after the em- 
 
FECUNDATION AND DEVELOPMENT OF THE OVUM. 215 
 
 bryo begins to develop, and is formed by the folds of the 
 epiblast and the external layer of the mesoblast rising up 
 in front and behind and on each side ; these amniotic folds 
 gradually extend over the back of the embryo to a certain 
 point, where they coalesce and inclose a cavity, the amniotic 
 cavity. Soon after the development of the amnion the allant- 
 ois is formed ; this membrane is vascular. It encroaches 
 upon and takes the place of the external amniotic membrane, 
 and is covered with hollow villi, which also takes the place 
 of the villi of the amnion, and when this outer coat recedes 
 and becomes blended with the vitelline membrane, it consti- 
 tutes the chorion, the external covering of the embryo. 
 
 The Allantois. — The allantois is a highly vascular 
 growth, arising from the posterior portion of the peritoneal 
 cavity, which gradually pushes its way out through the am- 
 niotic folds, attaching itself to the outer layer of the amnion ; 
 finally, from increased growth, it completely surrounds the 
 embryo, and its edges become fused together. 
 
 Amniotic Fluid. — The process of the enlargement of the 
 amnion shows that the amniotic fluid gradually increases in 
 quantity as the development of the foetus progresses. At 
 term the entire quantity is variable, being rarely more than 
 two pints ; the average is about one pint. It is a clear, trans- 
 parent fluid containing albumin, glucose, fatty matter, urea 
 and inorganic salts, etc. Its reaction is usually neutral or 
 faintly alkaline, though sometimes it is feebly acid in the 
 latest periods of pregnancy. 
 
 The Chorion. — The external investment of the embryo 
 is formed by a fusion of the original vitelline membrane, the 
 external layer of the amnion, and the allantois. The exter- 
 nal surface now becomes covered with villous processes, 
 which increase in number and size by the continued budding 
 and growth of club-shaped processes from the main stem, 
 and gives to the chorion a. shaggy appearance. They consist 
 
2l6 COMPEND OF HUMAN PHYSIOLOGY. 
 
 of a homogeneous granular matter, and are penetrated by 
 branches of the blood-vessels derived from the aorta. 
 
 At about the end of the second month the villosites begin 
 to atrophy and disappear from the surface of the chorion, 
 with the exception of those situated at the points of entrance 
 of the foetal blood-vessels, which occupy about one-third of 
 its surface, where they continue to grow larger, become more 
 vascular, and ultimately assist in the placenta ; the remain- 
 ing two-thirds of the surface lose its villi and blood-vessels, 
 and become a simple membrane. As the ovum enlarges over 
 a certain area surrounding the point of attachment of the 
 pedicle which connects the chorion with the embryo, the 
 villi are developed more rapidly than over the rest of the 
 surface. 
 
 Umbilical Cord — Connects the foetus with that part of 
 the chorion which forms the foetal side of the placenta. It 
 is a process of the allautois, and connects two arteries and a 
 vein, which have a more or less spiral direction. It appears 
 at the end of the first month, and gradually increases in 
 length, until at the end of gestation it measures about twenty 
 inches. The cord is also surrounded by a process of the 
 amnion. It is usuall3 r about the size of the little fiuger, and 
 will sustain a weight of about twelve pounds. 
 
 Membrane Decidil£. — In addition to the two mem- 
 branes connected with the foetus, there are two membranes 
 formed from the mucous membrane of the uterus, which are 
 derived from the mother, and which serve still further to pro- 
 tect the ovum. The anterior of the uterus is lined by a thin, 
 delicate mucous membrane, in which are imbedded immense 
 numbers of tubules, terminating in blind extremities, the 
 uterine tubules. At each period of menstruation the mucous 
 membrane becomes thickened and vascular, which condition, 
 however, disappears after the usual menstrual discharge. 
 When the ovum becomes fecundated the mucous membrane 
 
FECUNDATION AND DEVELOPMENT OE THE OVUM. 217 
 
 takes on a new growth, becomes more hypertrophied and 
 vascular, sends off little processes or elevations from its sur- 
 face, and constitute the decidua vera. 
 
 As development advances, the decidua vera becomes ex- 
 tended, loses its vessels and glands, and is reduced to the 
 condition of a simple membrane, or, rather, decidua reflexa, 
 which is thinner than the decidua vera, and grows up on all 
 sides and inclose the ovum, while the villous processes 'of 
 the chorion insert themselves into the uterine tubules, and in 
 the mucous membrane between them. 
 
 The PiAcenta. — At about the end of the second month 
 the villi of the chorion become enlarged and arborescent over 
 that part which eventually forms the foetal portion of the 
 placenta. They are then highl} r vascular and are imbedded 
 in the soft substance of the hypertrophied mucous mem- 
 brane. At the same time the villi over the rest of the cho- 
 rion are arrested in their growth, and they finally disappear 
 during the third month. The blood vessels penetrate the 
 villi in the form of loops at about the fourth week, and the 
 placenta is distinctly marked at about the end of the third 
 month. The placenta then rapidly assumes the anatomical 
 characters observed after it may be said to be fully de- 
 veloped. 
 
 The fully formed placenta occupies about one-third of the 
 uterine mucous membrane, is generally rounded or ovoid in 
 shape, and of all the embryonic structures, the placenta is 
 the most important. It is seven to nine inches in diameter, 
 six to eight inches in breadth and about one inch thick at the 
 point of penetration by the umbilical cord. Its weight va- 
 ries from fifteen to thirty ounces. It is most frequently situ- 
 ated at the upper and posterior part of the inner side of the 
 uterus. 
 
 The placenta is composed of two portions, a foetal and a 
 maternal portion. The foetal portion is formed by villi of the 
 
2l8 COMPEND OF HUMAN PHYSIOLOGY. 
 
 chorion, which by developing, rapidly increases in size and 
 number. They become branched and penetrate the uterine 
 tubules, which enlarge and receive their many ramifications. 
 The capillary blood vessels in the anterior of the villi also 
 enlarge and freely anastomose with each other. 
 
 The maternal portion is formed from that part of the hy- 
 pertrophied and vascular decidual membrane, between the 
 ovum and the uterus, the decidua serotina. As the placenta 
 increases in size the maternal blood-vessels around the tu- 
 bules become more and more numerous, and gradually fuse 
 together, forming great lakes, which constitute sinuses in 
 the walls of the uterus. 
 
 In the human subject, the maternal and foetal substances 
 are so closely united that they can not be separated from 
 each other, and as the latter period of gestation approaches 
 the villi is extended deeper into the decidua, while the 
 sinuses in the maternal portion become large and extend far- 
 ther into the chorion. Finally, from excessive development 
 of the blood-vessels, the structure between them disappears, 
 and as their walls come in contact they fuse together so that 
 ultimately the maternal and fcetal blood are only separated 
 by a thin layer of a homogeneous substance. When fully 
 formed the placenta consists principally of blood-vessels in- 
 terlacing in every direction. The blood from the mother 
 passes from the uterine vessels into the reservoirs (or lakes) 
 surrounding the villi ; but there is not at any time an inter- 
 mingling of blood, the two being separated by a delicate 
 membrane formed by a fusion of the walls of the blood-ves- 
 sels and the walls of the villi and uterine sinuses. 
 
 The function of the placenta, besides nutrition, is that of 
 a respiratory organ, permitting the oxygen of the maternal 
 blood to pass by osmosis through the delicate placental mem- 
 brane into the blood of the foetus ; at the same time permit- 
 ting carbonic acid and other waste materials, the result of 
 
DEVELOPMENT OF THE EMBRYO. 219 
 
 nutritive changes in the foetus, to pass into the maternal 
 blood, to be carried off through various eliminating organs. 
 Through the placenta also pass all the nutritive materials of 
 the maternal blood, which are essential for the development 
 of the embryo. In other words, the placenta is to the em- 
 bryo what the lungs and stomach are to the man. 
 
 CHAPTER XLIX. 
 
 DEVELOPMENT OF THE EMBRYO. 
 
 The Ovum. — The product of generation retains the name 
 of ovum until the form of the body begins to be apparent, 
 when it takes the name of embryo. At the fourth month, 
 about the time of quickening, it takes the name of fcstus, a 
 name which it retains during the rest of intra-uterine life. 
 
 Nervous System. — In reading your anatomy on the 
 development and ossifications of the spinal column, how the 
 dorsal or medullary plates close over the groove for the neu- 
 ral canal, and how in the interior of this canal the cerebro- 
 spinal axis is developed by cells which gradually encroach 
 upon its caliber until there remains only the small central 
 canal of the spinal cord, communicating with the ventricles 
 of the brain. 
 
 The external surface of this canal gives rise to the dura 
 ?nater and pia-mater. The neural canal thus formed is a 
 tubular membrane ; it terminates posteriorly in an oval dila- 
 tation, and anteriorly in a bulbous extremity, which soon 
 become partially contracted and forms the anterior, middle, 
 and posterior cerebral vesicles, from which are ultimately 
 developed the cerebrum, the corpora quadrigemina, and me- 
 dulla oblongata, respectively. 
 
220 COMPEND OF HUMAN PHYSIOLOGY. 
 
 The nerves are not produced as prolongations from the 
 spinal cord into various tissues, nor do they extend from the 
 tissues to the cord, but they are individually developed in 
 each tissue, by a separation of histological elements, from 
 the cells of which the parts are originally constituted. The 
 nerves of the sympathetic system are developed in the same 
 way. 
 
 The mode of development of the spinal cord is thus very 
 simple ; but with the growth of the embryon dilatations are 
 observed at the superior and at the inferior extremities of the 
 neural canal. The cord is nearly of uniform size, in the dor- 
 sal regions, marked only by the regular enlargements at the 
 sites of origin of the spinal nerves ; but there soon appears 
 an ovoid dilatation below, which forms the lumbar enlarge- 
 ment, from which the nerves are given off to the inferior 
 extremities, and the branchial enlargements above, where 
 the nerves of the superior extremities take their origin. The 
 anterior vesicle soon subdivides into two secondary vesicles, 
 the larger of which becomes the hemispheres, the smaller 
 the optic thalami ; the posterior vesicle also divides into two, 
 the anterior becoming the cerebellum, the posterior the pons 
 Varolii and medulla oblongata. 
 
 While this division of the primitive cerebral vesicles is 
 going on, the entire chain of encephalic ganglia becomes 
 curved from behind forward, forming three prominent angles. 
 As development advances the relative size of the encephalic 
 masses change ; the cerebrum developing more rapidly than 
 the posterior portion of the brain, soon grows backward and 
 arches over the optic thalami and the tubercula quadrigemina; 
 the cerebellum overlaps the medulla oblongata. At first the 
 surface of the cerebral hemispheres is smooth, but at about 
 the fourth mouth it begins to be marked by future fissures 
 and convolutions. 
 
 So far as the action of the nervous system of the foetus is 
 
DEVELOPMENT OF THE EMBRYO. 22 1 
 
 concerned, it is probably restricted mainly to reflex phenom- 
 ena depending upon the spinal cord, and that perception and 
 volition hardly exists ; but there is no doubt that many reflex 
 movements takes place in utero. When a foetus is removed 
 from the uterus of animals, even in the early months of preg- 
 nancy, movements of respiration occur ; and it is well known 
 that efforts of respiration sometimes take place within the 
 uterus. These are due to the want of oxygen-carrying 
 blood in the medulla oblongata when the placental circula- 
 tion is interrupted. 
 
 Development of Digestive Apparatus. — The intestinal 
 canal is the first formation of the digestive system. This is 
 at first open in the greater part of its extent, presenting, at 
 either extremity of the longitudinal gutter, in front of the 
 spinal column, a rounded, blind extremity, which is closed 
 over in front for a short distance. The close of the visceral 
 plains then extend laterally and from the two extremities 
 of the intestine, until only the opening remains for the pass- 
 age of the umbilical cord and the pedicle of the umbilical 
 vesicle. There is at first an opening communicating between 
 the lower part of the intestinal tube and the allantois, which 
 forms the canal known as the urachus ; but that portion of 
 the communication which remains closed in the abdominal 
 cavity, becomes separated from the urachus, is dilated and 
 eventually forms the urinary bladder. When the bladder is 
 first shut off" it communicates with the lower portion of the 
 intestine, which is called the cloaca ; but it finally loses this 
 connection and presents a special opening, the urethra. As 
 development advances the intestine grows rapidly in length 
 and becomes convoluted. It is held loosely to the spinal col- 
 umn by the mesentery, a fold of the peritoneum, this mem- 
 brane being reflected along the walls of the abdominal cav- 
 ity. At the upper part of the alimentary canal and anterior 
 portion, two pouches appear, which become the cardiac and 
 
22 2 COMPEND OF HUMAN PHYSIOLOGY. 
 
 pyloric extremities of the stomach. At about the seYenth 
 week the inferior extremity of the intestine is brought into 
 communication with the exterior, by an opening, the anus. 
 Anteriorly the mouth and pharynx are formed by an invo- 
 lution of epiblast, which gradually deepens until it com- 
 municates with the fore-gut. A short distance below the at- 
 tachment of the pedicle of the umbilical vesicle to the intes- 
 tine appears a rounded diverticulum, which is eventually 
 developed into the caecum, which gradually recedes from the 
 vicinity of the umbilicus, which is its original situation, and 
 finally becomes fixed by a shortening of the mesentery in 
 the right iliac region. 
 
 The development of the amis is very simple. At first the 
 intestine terminates below in a blind extremity, but about 
 the seventh week a longitudinal slit appears below the ex- 
 ternal organs of generation, by which the rectum opens. 
 This is the anus. The opening of the anus appears about 
 a week after the opening of the mouth, at or about the 
 seventh week. 
 
 The Liver — Appears very early and, indeed, at the end 
 of the first month this organ has attained a large size. It 
 first appears as a slight rudimentary protrusion from the 
 side of the alimentary canal. It grows very rapidly, and at- 
 tains a large size, and almost fills up the abdominal cavity. 
 The hepatic cells are derived from the intestinal epithelium, 
 the vessels and connective tissue from the mesoblast. Dur- 
 ing the early part of foetal life the liver is proportionately 
 larger than later, and its weight compared to the weight of 
 the body at different ages is as follows : At the end of the 
 first month, i to 3 ; at four to five months, 1 to 6 ; at term, 
 1 to 18 ; in the adult, 1 to 36. (Burdach.) 
 
 The Pancreas — Appears at the left side of the duo- 
 denum by the formation of two ducts leading from the intes- 
 tines, which branch and develop glandular structure at their 
 
DEVELOPMENT OF THE EMBRYO. 223 
 
 extremities. The spleen is developed about the same time, 
 at the greater curvature of the stomach, and becomes distinct 
 during the second month. 
 
 The Lungs are developed from the anterior portion of the 
 oesophagus. At first a small bud appears which, as it 
 lengthens, divides into branches ; secondary and tertiary pro- 
 cesses are given off these, which form the bronchial tubes 
 and air cells. The lungs at first extend in the abdominal 
 cavity, but become confined to the thorax by the develop- 
 ment of the diaphragm. 
 
 The Bladder — Is formed by a dilatation of that portion 
 of the allantois remaining within the abdominal cavity. It 
 is at first pear-shaped, and communicates with the intestine, 
 but later becomes separated and opens externally by the 
 urethra. It is attached to the abdominal walls by a rounded 
 cord, the uracus, the remains of a portion of the allantois. 
 
 The Face. — The anterior portion of the embryon re- 
 mains open in front long after the medullary plates have met 
 at the back and inclosed the neural canal. The common 
 cavity of the thorax and abdomen is closed by the growth of 
 the visceral plates which meet in front. In the facial and 
 cervical regions the visceral laminae send up three processes, 
 the visceral arches, separated by clefts, the visceral clefts. 
 
 From the above sketch it is seen that the face and neck are 
 formed by the advance and closure in front of projections 
 from behind, in the same way as the cavities in the thorax 
 and abdomen are formed. The first, or the mandibular arches, 
 unite in the median line to form the lower jaw, and superi- 
 orly from the malleus, but it must be remembered that in the 
 very first stage of development of the head there is no ap- 
 pearance of a face. 
 
 A process jutting from the visceral arches (or the first for- 
 mation) grows forward from its base and unites with the 
 fronto-nasal process growing from above, and forms the 
 
224 COMPEND OF HUMAN PHYSIOLOGY. . 
 
 upper jaw. When the superior maxillary processes fail to 
 unite, there results the cleft-palate deformity ; if the integu- 
 ment also fails to unite, there results the hare-lip deformity. 
 The space above the mandibular arch becomes the mouth. 
 
 The second visceral arch advances and forms the incus and 
 stapes bones, the styloid process and ligaments, and the 
 lesser cornua of the hyoid bone. The cleft between the first 
 and second arches partially close up, but there remains 
 an opening at the side which becomes the Eustachian tube, 
 tympanic cavity, and external auditory meatus. The third 
 and fourth arches develop respective^ into the body of the 
 greater cornua of the hyoid bone, and into sides of the neck 
 and the larynx, the arytenoid cartilage having developed 
 first. In front of the larynx and just behind the tongue is a 
 little elevation which is developed into the epiglottis. The 
 openings of the nostrils appear during the second month ; a 
 little elevation, the nose, appears between these openings, 
 and the nasal cavity begins to be distinct from the mouth. 
 The lips are distinct during the third month, the tongue 
 about the seventh week. 
 
 The Eye — Is formed by a little bud projecting from the 
 side of the anterior vesicle. It is at first hollow, but soon 
 becomes filled with nervous matter, forming the optic nerve 
 and the retina ; the remainder of the cavity is filled with 
 the vitreous body. The anterior portion of the pouch 
 becomes invaginated and receives the crystalline lens, which 
 is a product of the epiblast, as is also the cornea. The iris 
 appears as a circular membrane without a central aperture, 
 about the seventh week. The eyelids are formed between 
 the second and third month. 
 
 The Internal Ea.r — Is developed from the auditory 
 vesicle, budding from the third cerebral vesicle ; the mem 
 braneous vestibule appears first, and from it diverticula 
 are given off, which become the semi-circular canals and 
 
DEVELOPMENT OE THE EMBRYO. 225 
 
 cochlae. The cavity of the tympanum, the Eustachian tube. 
 and the external auditory canal are remains of the first 
 branchial cleft ; the cavity of this cleft being subdivided 
 into the tympanum and external auditory meatus by the 
 membrana tympani. 
 
 The Skeleton.— In the development of the embryon, 
 one of the structures observed is the iwtochord. This is 
 situated beneath the neural canal and extends the entire 
 length of the body. It is formed of a cord of simple cells. 
 and marks the situation of the vertebral column, though it 
 is not itself developed into the vertebrae, which grows 
 around it and encroaches upon its substance until it finally 
 disappears. In many mammals the notochord presents a 
 slight enlargement at the cephalic extremity, which extends 
 to the auditory vesicles, and it is considerably reduced in 
 size at the caudal extremity. By the sides of this cord are 
 masses of cells which unite in front of the neural canal 
 and are eventually developed into the vertebra. These are 
 called protovei tebrcc or somites. 
 
 These cells extend around and encroach upon the chorda 
 dorsalis, forming the bodies of the vertebrae. They also 
 extend over the neural canal, closing above, and their 
 processes are called the medullary, or dorsal plates Some- 
 times the dorsal plates fail to close at a certain point in the 
 spinal column, and this constitutes the malformation known 
 as spina bifida. From the sides of the bodies of the ver- 
 tebrae the various processes are formed, and as the spinal 
 column is developed its lower portion presents a projection 
 beyond the plevis which constitutes a temporary caudal 
 appendage, curved toward the abdomen ; but this no longer 
 projects after the bones of the pelvis are fully developed. 
 At the same time the entire vertebral column is curved 
 toward the abdomen and it is twisted upon its axis, from 
 left to right, so that the anterior face of the pelvis presents 
 15 
 
226 COMPEND OF HUMAN PHYSIOLOGY. 
 
 a right angle to the upper part of the body ; but as the 
 inferior extremities and the pel\ T is are developed the spine 
 becomes straight. The vertebrae make their appearance 
 first in the middle of the dorsal region, from which point 
 they rapidly extend upward and downward until the spinal 
 column is complete. 
 
 At the base of the skull, on either side of the superior 
 prolongation of the chorda dorsalis, are two cartilaginous 
 processes, which are developed into the so-called cranial 
 vertebrae. In this cartilaginous mass three ossific points 
 appear, one behind the other. The posterior point of ossi- 
 fication is for the basilar portion of the occipital bone, the 
 middle point is for the sphenoid, and the anterior point is 
 for the anterior portion of the sphenoid. They are ulti- 
 mately developed into the basilar process of the occipital 
 bone and the body of the sphenoid. 
 
 The entire skeleton is at first either membraneous or car- 
 tilaginous. At the beginning of the second month centers 
 of ossification appear in the jaws and clavicle. As develop- 
 ment advances, the ossific points in all the future bones ex- 
 tend until ossification is complete. The upper and lower 
 jaws and clavicle ossify about the same time from little bony 
 prominences at about the beginning of the second month of 
 intra-uterine life. 
 
 Other ossific points, which gradually extend, are also seen 
 in other parts, the head, ribs, pelvis, scapula, metacarpus 
 and metatarsus, and the phalanges of the fingers and toes. 
 At birth the carpus is cartilaginous, and remains so until 
 the second year. 
 
 As ossification progresses, the deposit in the various os- 
 sific points gradually encroaches until it reaches the joints, 
 which remain encrusted with the permanent articular car- 
 tilage. 
 
 While the skeleton is thus developed, the muscles are 
 
DEVELOPMENT OF THE EMBRYO. 227 
 
 formed from the outer layer of the mesoblast, and the vis- 
 ceral plates close over the thorax and abdomen in front, 
 leaving an opening for the umbilical cord. The deeper lay- 
 ers of the muscular tissue begin to be distinct at the first of 
 the second month. The skin appears soon after the appear- 
 ance of the outer muscles, and is very delicate and trans- 
 parent. At the end of the second month the epidermis may 
 be distinguished. At the third month the nails make their 
 appearance, and the hairs begin to grow about the fifth 
 month. 
 
 Development of the Genito Urinary Apparatus. — 
 The genital and the urinary organs are developed together, 
 and are both preceded by the appearance of two large, sym- 
 metrical structures known as Wolffian bodies or the bodies 
 of Oken. These are sometimes called the false or the pri- 
 mordial kidneys. These appear at about the thirteenth day, 
 develop rapidly and on either side of the spinal column, and 
 are so large as to almost fill the cavity of the abdomen. The 
 Wolffian bodies consist of tubules which run transversely 
 and are lined with epithelium. Internally the} T become in- 
 vaginated to receive tufts of blood-vessels. Externally they 
 open into a common excretory duct, the duct of the Wolffian 
 body, which unites with the duct of the opposite body, and 
 empties into the intestinal canal at a point opposite the 
 allantois. On the outside of the Wolffian body there ap- 
 pears another duct, the duct of Muller, which also opens 
 into the intestine. 
 
 Very soon after the Wolffian bodies have made their ap- 
 pearance, there appear at their inner borders two ovoid 
 bodies, which are finally developed into the testicles for the 
 male or ovaries for the female. The testicles or ovaries are 
 developed at the internal or anterior surface of the Wolffian 
 bodies, first appearing in small, ovoid masses. The tubes 
 called the ducts of Muller, which begin just above and pass 
 
228 COMPKND OF HUMAN PHYSIOLOGY. 
 
 along the external borders of the Wolffian bodies, at 
 first open into the intestine near the point of entrance of 
 the Wolffian ducts. In the female their upper extremity 
 remains free, except the single fimbria, which is connected 
 with the ovary. Their inferior extremities unite with each 
 other, and at their point of union they form the uterus. 
 When this union is incomplete there is the malformation 
 known as double uterus, which may be associated w 7 ith a 
 double vagina. At about the fiftieth day the Wolffian 
 bodies and their ducts disappear. 
 
 In the female the ovaries pass down no farther than the 
 pelvic cavity ; but the testicles, which are at first in the ab- 
 domen of the male, finally descend into the scrotum. As 
 the testicles descend they carry with them the Wolffian 
 duct and that portion of the Wolffian body which is perma- 
 nent, constituting the head of the epididymis ; at the same 
 time a cord appears attached to the lower extremity of the 
 testicles and extending to the symphysis pubis. This is 
 called the gubernaculum. It is at first muscular, but the 
 muscular fibres disappear during the later periods of utero- 
 gestation. The epididymis and the vas deferens are formed 
 from the Wolffian body and duct. At about the end of the 
 seventh month the testicles have reached the internal ab- 
 dominal ring, and at this time a double "tubular process of 
 peritoneum, covered with a few fibres from the lower por- 
 tion of the internal oblique muscle of the abdomen, grad- 
 ually descend into the scrotum ; the testicle following the 
 process of peritoneum, which latter eventually becomes the 
 visceral and parietal portion of the tunica vaginalis. 
 
 At the eight or ninth month the testicles have reached 
 the external abdominal ring and then soon descend into the 
 scrotum. The vas deferens passes from the testicle, along 
 the base of the bladder, to open into the prostatic portion of 
 the urethra ; and as development advances two saculated di- 
 
DEVELOPMENT OF THE EMBRYO. 229 
 
 verticula from these tubes make their appearance, which 
 are attached to the bladder and constitute the vesiculae 
 seminales. As the ovaries descend to their permanent sit- 
 uation in the pelvic cavity there appears, attached to the in- 
 ner extremity of each, a rounded cord, analogous to the 
 gubernaculum testis. A portion of this, connecting the 
 ovary with the uterus, constitutes the ligaments of the 
 ovary, and the inferior portion forms the round ligaments 
 of the uterus, which pass through the inguinal canal and is 
 attached to the symphysis pubis. 
 
 Behind the Wolffian bodies, and developed entirely inde- 
 pendent of them, the kidneys, suprarenal capsules and 
 uterus make their appearance. The kidneys are 'developed 
 in the form of little rounded bodies, composed of short, 
 blind tubes, all converging toward a single point, which 
 is the hilum. 
 
 These tubules increase in length, branch and become 
 convoluted in certain parts of their extent, finally assume 
 the structure and arrangement of renal tubules with their 
 Malpighian bodies, blood-vessels, etc. They all open into 
 the hilum, and during the formation of the kidneys the 
 suprarenal capsules are formed at their superior extrem- 
 ities. 
 
 These bodies, the uses of which are unknown, are rela- 
 tively so much larger in the foetus than in the adult that 
 they have been supposed to be peculiarly important in in- 
 tra-uterine life, though nothing definite is known upon the 
 point. 
 
 The kidneys are relatively very large in the foetus. Their 
 proportion to the weight of the body in the foetus is one to 
 eighty, and in the adult one to two hundred and forty. 
 There is but little doubt that the ureters are developed as 
 tubular processes from the kidneys, which finally extend 
 to open into the bladder. 
 
23O COMPEXD OF HUMAN PHYSIOLOGY. 
 
 External Organs of Generation — Begin to be de 
 veloped about the fifth week. At the inferior extremity of 
 the body of the embryon a small ovoid eminence appears 
 in the median line, at the lower portion of which there is a 
 longitudinal slit which forms the common opening of the 
 anus and the genital and urinary passages. This is the 
 cloaca. Soon there is formed a septum which divides the 
 rectum from the vagina, the urethra of the female opening- 
 above. From the median prominence in the male two 
 lateral rounded bodies make their appearance ; these are 
 developed into the glans penis and corpora cavernosa; in 
 the female, from this prominence, are developed the clitoris 
 and the labia minora. 
 
 In the male these two lateral prominences unite in the 
 median line and form the spongy portion of the urethra, 
 while in the female there is a want of union and an opening 
 remains between the two labia minora, which is the true 
 vagina. 
 
 The scrotum in the male is analogous to the labia majora 
 in the female ; the distinction being that the two sides of 
 the scrotum unite in the median line, while the labia majora 
 remains permanently separated. This similarity is further 
 shown by the anatomy of inguinal hernia, in which the in- 
 testines descend into the labium in the female and in the 
 scrotum in the male. 
 
 The Circulatory Apparatus. — The blood and blood 
 vessels develop very early in foetal life, and assume three 
 different forms at different periods of life, all having refer- 
 ence to the manner in which the embryo receives nutritious 
 matter and eliminates products of waste. Vitelline circula- 
 tion appears first and absorbs nutritious materials from the 
 vitellus. It is formed by blood-vessels which emerge from 
 the body and ramify over a portion of the vitelline mem- 
 brane composing the area vasculosa. The heart lying in the 
 
DEVELOPMENT OF THE EMBRYO. 23 1 
 
 median line, gives off two arches, which unite to form 
 the abdominal aorta, from which two large arteries are 
 given off, passing into the vascular area ; the venous blood 
 is returned by veins which enter the heart. These vessels 
 are known as the omphalo-mesenteric arteries and veins. The 
 vitelline circulation is of short duration in the mammals, 
 as the supply of nutritious matter in the vitellus soon 
 becomes exhausted ; however, nutritive matter is absorbed 
 almost exclusively from the mother, by a simple endos- 
 mosis, before the placental circulation is established, and by 
 the placental vessels at a later period. 
 
 The Placentae Circulation — Becomes established 
 when the blood-vessels in the allantois enter the villous 
 processes of the chorion and come into close relationship 
 with the maternal blood-vessels. This circulation lasts 
 the whole of intra-uterine life, but gives way at birth to 
 the adult circulation, the change being made possible by 
 the development of the true circulatory apparatus. 
 
 The Heart. — The central enlargement of the vascular 
 system in the first circulation, which becomes the heart, is 
 twisted upon itself by a single turn. The portion which is 
 connected with the cephalic extremity of the embryon gives 
 origin to the arterial system, and the portion connected w 7 ith 
 the caudal extremity receives the blood from the venous 
 system. The w 7 alls of the arterial portion of the heart soon 
 become thickened, while the walls of the venous portion 
 comparatively remain thin. There then appears a constric- 
 tion, which partly separates the auricular from the ventric- 
 ular portion. 
 
 At a certain period of development, the heart presents a 
 single auricle and a single ventricle. 
 
 The division of the heart into two ventricles appears 
 before the tw T o auricles are separated. This division is 
 caused by a septum, which gradually extends from the apex 
 
232 COMPKND OF HUMAN PHYSIOLOGY. 
 
 of the heart upwards toward the auricular portion; how- 
 ever, at about the end of the second month a septum begins 
 to be formed between the auricles. This extends from the 
 base of the heart toward the ventricles, but it leaves an 
 opening between the two sides — the foramen ovale, or the 
 foramen of Botal — which persists during the whole of foetal 
 life. 
 
 At the anterior edge of the opening of the vena cava as- 
 cendens into the right auricle there is a membraneous fold 
 projecting into the auricle. This is called the valve of 
 Kustachius, and it divides the right auricle incompletely 
 into two portions. 
 
 During the sixth week the heart is vertical and is situated 
 in the median line, with the aorta arising from the center 
 of its base. At the end of the second month it is raised up 
 by the development of the liver and its point presents for- 
 ward. During the fourth month it is twisted slightly upon 
 its axis and the point is inclined to the left. At this period 
 the auricular portion is larger than the ventricles, but the 
 auricles diminish in their relative capacity during the latter 
 half of intra-uterine life. The pericardium makes its ap- 
 pearance during the ninth month. In early intra-uterine 
 life the relative size of the heart is very great. The pro- 
 portion gradually diminishes, until at birth the ratio is 
 nearing the normal. At first it is said to be as one to fifty , 
 at term one to one hundred and twenty, and in the adult 
 one to one hundred and sixty. During about the first half 
 of intra-uterine life the thickness of the two ventricles is 
 nearly the same, but after that time the relative thickness 
 of the left ventricle gradually increases. 
 
 Fcetal Circulation. — Beginning at abdominal aorta, 
 the blood passes into the two primitive iliacus and thence 
 into internal iliacus. From the two internal iliacus the two 
 hypogastric arteries arise, which ascend along the sides of 
 
DEVELOPMENT OF THE EMBRYO. 233 
 
 the bladder to its fundus, pass to the umbilicus and go to 
 the placenta, forming the two umbilical arteries. In this 
 way the blood of the foetus finds its way to the placenta. 
 
 The umbilical vein enters the body of the foetus at the 
 umbilicus ; it passes along the margin of the suspensory 
 ligament to the under surface of the liver; it gives off one 
 branch of large size, and one or two smaller ones to the 
 left lobe ; it sends a branch each to the lobus quadratus and 
 the lobus Spigelis, and the vessel reaches the transverse 
 fissure. At the transverse fissure it divides into two 
 branches, the larger of which joins the portal vein and 
 enters the liver, and the smaller, which is the ductus 
 venosus, passes to the vena cava ascendens, at the point 
 where it receives the left hepatic vein. Thus the greater 
 part of the blood returned to the foetus from the placenta 
 passes through the liver, a relatively small quantity being 
 emptied into the vena cava by the ductus venosus. 
 
 Containing the placental blood is the vena cava ascendens 
 which pass through the liver, the blood conveyed directly 
 from the umbilical vein by the ductus venosus, and the 
 blood from the lower extremities passes to the right auricle. 
 As the blood enters the right, auricle, it is directed by the 
 Eustachian valve, passing behind the valve, through the 
 foramen ovale, into the left auricle. At the same time the 
 blood from the head and superior extremity passes down 
 by the vena cava descendens in front of the Eustachian 
 valve, through the right auricle into the right ventricle. 
 The Eustachian valve is so arranged that the right auricle 
 simply affords a passage for the two currents of blood ; the 
 one from the vena cava ascendens through the foramen 
 ovale, pass into the left auricle and left ventricle, and the 
 other from the vena cava descendens, pass through the 
 right auriculo-ventricular opening into the right ven- 
 tricle, 
 
234 COMPEND OF HUMAN PHYSIOLOGY. 
 
 It is probable, indeed, that there is very little admixture 
 of those two currents of blood in the natural course of 
 foetal circulation. 
 
 The blood passes into the left auricle from the vena cava 
 ascendens through the foramen ovale, passes from the left 
 auricle to left ventricle ; the two also receive a small quan- 
 tity of blood from the lungs by the pulmonary veins. 
 There the left ventricle is filled ; at the same time the right 
 ventricle is filled with blood which has passed through the 
 right auricle in front of the Eustachian valve. The two 
 ventricles thus distend, then contract simultaneously. The 
 blood from the right ventricle passes in small quantities to 
 the lungs, the greater part passing through the ductus arteri- 
 osus into the descending portion of the arch of the aorta. 
 This duct is about one-half inch in length and about the 
 size of a goose quill. The blood from the left ventricle 
 passes into the aorta and goes to the system. 
 
 At birth, the placental circulation gives way to the adult 
 circulation. After a short w T hile the sense of want of air 
 becomes sufficiently intense to give rise to an inspiratory 
 effort and the first inspiration is made. As soon as the 
 child begins to breathe, the lungs expand, blood flows freely 
 through the pulmonary capillaries and the ductus arteriosus 
 begins to contract. The foramen ovale closes about the 
 tenth day. The umbilical vein and ductus venosus become 
 impervious in from three to ten days, and ultimately form 
 rounded cords. 
 
 The hypogastric arteries remain pervious at their lower 
 portion, and constitute the superior vesical arteries. A 
 rounded cord, which is the remnant of the umbilical, forms 
 the round ligament of the liver. A slender cord, the rem- 
 nant of the ductus venosus, is lodged in a fissure of the 
 liver, called the fissure of the ductus venosus. 
 
FINALE. 235 
 
 CHAPTER L. 
 
 FINALE. 
 Points worth Remembering, 
 
 Largest Artery — Abdominal aorta. 
 
 Largest Nutrient Artery — Tibial. 
 
 Largest Synovial Membrane — At the knee joint. 
 
 Largest Muscle — Glutaeus maximus. 
 
 Largest Nerve — Sciaticus magnus. 
 
 Largest Vein — Vena cava. 
 
 Longest Muscle — Sartorius. 
 
 Longest Tendon — Plantaris. 
 
 Branchless Artery — Common carotid (except the terminal 
 branches). There are also no branches from the cervical 
 portion of the internal carotid. 
 
 Veins Carrying Arterial Blood — Pulmonary. (In the 
 foetus, the veins carrying arterial blood are the umbilical, 
 hepatic and inferior vena cava). 
 
 Ai'tery Carrying Venous Blood — Pulmonary. (In foetus, 
 umbilical, also). 
 
 Nerve Perforated by an Artery — Sciatic by the comes 
 nervi ischiadici; the arteria centralis retinae also pierces 
 the optic nerve. 
 
 Nerve Perforated by a Vein — Those just named. 
 
 Muscle Perforated by a Muscle — Stylo-hyoid by the digas- 
 tric. 
 
 Muscle Perforated by a Large Nerve — Coraco-brachialis by 
 the musculo-cutaneus. 
 
 Vein Perforated by a Nerve — Occasionally the axillary vein 
 by the internal anterior thoracic nerve. 
 
 Ligament Perforated by a Nerve — Sacro-sciatic by the an- 
 terior branch of the coccygeal nerve. 
 
236 COMPKND OF HUMAN PHYSIOLOGY. 
 
 Ligament Pierced by an Arterj — The greater sacro-sciatie, 
 by the coccygeal branch of the sciatic artery. The azygos 
 articularis artery also pierces the posterior ligament of the 
 knee joint. 
 
 Membrane Pierced by an Artery — The thyro-hyoid by the 
 superior laryngeal artery. 
 
 Tendons Perforated by Tendons — Those of the flexor sub- 
 limis digitorum, of the hands, for the passage of the tendons 
 of the flexor profundus digitorum. In the feet, the tendons 
 of the flexor brevis digitorum are split for the passage of 
 the tendons of the flexor longus digitorum. 
 
 Largest Branch of the Internal Carotid Artery — Is the mid- 
 dle cerebral; this is the artery that is liable to become 
 plugged by an embolus. 
 
 Bones with no Muscular Attachments — Ten ; ethmoid, na- 
 sal, inferior turbinated, vomer, scaphoid, semi-lunar cunei- 
 form, astragalus, middle cuneiform, incus. 
 
 Pillars of the Palate — Anterior, formed by projection of 
 palato-glossus muscle ; posterior, by projection of palato- 
 pharyngeus muscle. 
 
 False Vocal Cords — Formed by superior thyro-arytaenoid 
 ligaments. 
 
 True J'ocal Cords — Formed by the inferior thyroarytenoid 
 ligaments. 
 
 Hamstrings — Outer formed by tendon of biceps ; inner, 
 by the tendons of the gracilis, sartorius, semi-membranosus, 
 and semi-tendinosus. 
 
 The Palatal Veins and Muscles, called Azygos — Are double, 
 although the term azygos signifies not paired. 
 
 Veins with Only Epithelial Walls — Those of the diploe. 
 
 Amnios was a term given us by Empedocles (B. C. 450). 
 Aorta was named by Aristotle (B. C. 384), though he sup- 
 posed it contained air. 
 
FINALE. 237 
 
 Cataract — The first removal of the lens for this disease 
 was made by Herophilus. Celsns cured the trouble by de- 
 pressing the lens (couching?). 
 
 Dissection — First human dissection after Herophilus' time 
 (Herophilus is said to have dissected 700 subjects) was by 
 Mondini de Luzzi, Professor of Anatomy at Bologna. Old 
 Alexandria, in times before our era, was famous as being 
 the possessor of two human skeletons; all Greece and Rome 
 flocked there to see them. Montagaua (A. D. 1460) boasted 
 that he had examined fourteen human subjects. 
 
 Duodenum was named by Herophilus ; he also showed 
 the heart to be the beginning of arterial circulation. In 
 fact, he is the father of anatomy. Fallopius (16th cen- 
 tury) said of him, "That to contradict him, was like con- 
 tradicting the gospels;" that he was "the evangelist of 
 anatomists." 
 
 Gynecologists — The most prominent ones of early date, 
 so far as surgical procedures are concerned, were Paulus 
 iEgineta (early part of the 7th century), though Aetius 
 (close of the 5th century), Galen (A. D. 131), Soranus (A. D. 
 98-138), Celsus (about A. D. 60), and even Hippocrates (460 
 B. C.) treated quite lengthily of the subject. Indeed five 
 Hippocratic treatises on female troubles were, in early days, 
 in the hands of the medical profession. 
 
 Leeches were first employed by Themison (B. C. 30). 
 
 Lexicographer, Medical. The first one was Rufus Kphe- 
 sius, about A. D. 98 or 117. 
 
 Litholo?ny was extensively practised in old Alexandria, 
 and the famous oath of Hippocrates (460 B. C.) recognized 
 it as undignified for the physician and surgeon. 
 
 Nerves — Their functions were discovered by Herophilus ; 
 he overthrew the doctrine that they sprang from the brain - 
 membranes, and proved them to come from the brain itself; 
 their crossing \ near their cranial organ, was first proposed 
 
238 COMPEND OF HUMAN PHYSIOLOGY. 
 
 by Aretaeus, and he, in this way, accounted for a left-sided 
 head injury resulting in a right-sided paralysis. 
 
 Physician—This term was first applied to doctors by the 
 people of Charlemagne, A. D. 805. 
 
 Pharmacopeia — The first one was issued by an Arabian s 
 Sabor-Ebr-Sahil (9th century) and was called Krabadin. 
 
 Rhinoplasty was devised by Vincent Vianso, an Italian, 
 who lived in the 15th century; also performed by Brauca 
 and Bojani. 
 
 Vein valves were first discovered by Fabrieius, during the 
 latter portion of the 10th century. 
 
 Tricuspid valves of the vena cava were discovered by Era- 
 sistratus, a contemporary of Herophilus. He called them 
 triglochine. 
 
 Torcula Herophili first described (with Calamus scriptorius) 
 and named by Herophilus (about 250 B. C). 
 
 Tinctures were first introduced by Arnold, about the year 
 1315. He was then a professor at Barcelona. 
 
 Cardiac and Pulmonic Circulation — The venae cavae 
 receive the systemic venous blood, and convey it into the 
 right auricle ; then it passes into the right ventricle through 
 the tricuspid, or auriculo-ventricular valves, to be thrown 
 into the pulmonic artery (going through the semilunar, or 
 pulmonary valves) ; is then conveyed to the lungs an4 oxy- 
 genized in the capillary plexus about the intercellular struct- 
 ure and the air-cells, and returned, by the pulmonary veins 
 (4 in number) to the left side of the heart into the left au- 
 ricle ; it then passes into the left ventricle (through the mi- 
 tral valve) to be forced with fifty-one and one-half pounds 
 into the aorta (through the semilunar valves), and from 
 thence to support the system at large. 
 
 Foetal Circulation. — From the placenta through the 
 umbilical vein to the liver ; from thence, by the hepatic 
 veins and ductus venosus Arantii. to the inferior vena cava, 
 
FINALE. 239 
 
 to the right auricle ; the most of the current, guided by the 
 Eustachian valve, passes through the foramen ovale into the 
 left auricle, and from thence into the left ventricle, and from 
 thence into the aorta and system at large. A part of the 
 current, however, enters the right ventricle, is then forced 
 into the pulmonary artery, and from the imperviousness of 
 the foetal lungs is most all conveyed to the aorta by the 
 ductus arteriosus Botalli. The blood is at last conducted by 
 the umbilical arteries (branches of the internal iliac) to the 
 placenta for re-oxygenation. 
 
 TABLE OF PHYSIOLOGICAL CONSTANTS.' 1 ' 
 
 Mean height of male, 5 feet 6y 2 inches ; female, 5 feet 2 
 inches. 
 
 Mean weight of male, 145 pounds; of female, 121 pounds. 
 
 Number of chemical elements in the human body ; from 
 16 to 18. 
 
 Number of proximate principles in the human body ; 
 about 100. 
 
 Amount of water in body weighing 145 pounds ; 108 
 pounds. 
 
 Amount of solids in the body weighing 145 pounds; 36 
 pounds. 
 
 Amount of food required daily ; 16 ounces meat, 10 ounces 
 bread, 3^2 ounces of fat, 52 ounces of water. 
 . Amount of saliva secreted in 24 hours ; about 3^2 pounds. 
 
 Function of saliva ; converts starch into glucose. 
 
 Active principle of saliva ; ptyalin. 
 
 Amount of gastric juice secreted in 24 hours ; from 8 to 
 14 pounds. 
 
 Functions of gastric juice ; converts albumin into albu- 
 minose. 
 
 Bur p. a k e r . 
 
240 COMPEND OF HUMAN PHYSIOLOGY. . 
 
 Active principles of gastric juice ; pepsin and hydrochlo- 
 ric acid. 
 
 Duration of digestion ; from 3 to 5 hours. 
 
 Amount of intestinal juice secreted in 24 hours ; about 1 
 pound. 
 
 Function of intestinal juice ; converts starch into glu- 
 cose. 
 
 Amount of pancreatic juice secreted in 24 hours ; about 
 i 1 /* pounds. 
 
 Active principles of pancreatic juice ; trypsin, amylopsin 
 andsteapsin. Functions. — 1. Emulsifies fats. 2. Converts 
 albumin into albuminose. 3. Converts starch into glucose. 
 
 Amount of bile poured into the intestines daily ; about 
 2% pounds. Functions. — 1. Assists in the emulsification 
 of fats. 2. Stimulates the peristalic movements. 3. Prevent 
 putrefactive changes in the food. 4. Promotes the absorp- 
 tion of the fat. 
 
 Amount of blood in the body ; from 16 to 18 pounds. 
 
 Size of red corpuscles ; ^Vff of an inch. 
 
 Size of white corpuscles ; j-gVff °f an inch. 
 
 Shape of red corpuscles ; circular biconcave disks. 
 
 Shape of white corpuscles ; globular. 
 
 Number of red corpuscles in a cubic millimetre of blood 
 (the cubic -£% of an inch); 5,000,000. 
 
 Function of red corpuscles ; to carry oxygen from the 
 lungs to the tissues. 
 
 Frequency of the heart's pulsations per minute; 72, on 
 the average. 
 
 Velocity of the blood movement in the arteries; about 16 
 inches per second. 
 
 Length of time required for the blood to make an entire 
 circuit of the vascular system ; about 20 seconds. 
 
 Amount of air passing in and out of the lungs at each 
 respiratory act ; from 20 to 30 cubic inches. 
 
FINALE. 241 
 
 Amount of air that can be taken into the lungs on a 
 forced inspiration ; no cubic inches. 
 
 Amount of reserve air in the lungs after an ordinary ex- 
 piration ; 100 cubic inches. 
 
 Amount of residual air always remaining in the lungs ; 
 about 100 cubic inches. 
 
 Vital capacity of the lungs; 230 cubic inches. 
 
 Entire volume of air passing in and out of the lungs in 
 24 hours ; about 400 cubic feet. 
 
 Composition of the air ; nitrogen, 79.19; oxygen. 20.81, 
 per 100 parts. 
 
 Amount of oxygen absorbed in 24 hours; 18 cubic feet. 
 
 Amount of carbonic acid exhaled in 24 hours; 14 cubic 
 feet. 
 
 Temperature of the human body at the surface ; 98-j^ F. 
 
 Amount of urine excreted daily ; from 40 to 50 ounces. 
 
 Amount of urea excreted daily 5512 grains. 
 
 Specific gravity of urine; from 1.015 to 1.025. 
 
 Number of spinal nerves ; 31 pairs. 
 
 Number of roots of origin ; two ; 1st, anterior, motor ; 2d, 
 posterior, sensory. 
 
 Rate of transmission of nerve force ; about too feet per 
 second. 
 
 Number of cranial nerves; 12 pairs. 
 
 Nerves of special sense. — 1. Olfactory, or 1st pair. 2. 
 Optic, or 2d pair. 3. Auditory, or 8th pair. 4. Chorda 
 tympani for anterior 2 /z of tongue. 5. Branches of glosso- 
 pharyngeal, or 8th pair, for posterior T /i of tongue. 
 
 Motor nerves to eyeball and accessory structures ; motor 
 oculi, or 3d pair; pathetic, or 4th pair; abducens or 6th 
 pair. 
 
 Motor nerves to facial muscles ; portio dura, facial, or 7th 
 pair. 
 
 Motor nerve to tongue; hypoglossal, or 12th pair. 
 10 
 
242 COMPKND OF HUMAN PHYSIOLOGY. 
 
 Motor nerve to laryngeal muscles ; spinal accessory or 
 r ith pair. 
 
 Sensory nerve of the face ; tri-facial or 5th pair. 
 
 Sensory nerve of the pharynx ; glosso-pharyngeal or 9th 
 pair. 
 
 Sensory nerves of the lungs, stomach, etc ; pneumogastric 
 or 10th pair. 
 
 L,ength of spinal cord: 16 or 18 inches, weight i l / 2 
 ounces. 
 
 Point of decussation of motor fibres ; at the medulla 
 oblongata. 
 
 Point of decussation of sensory fibres ; throughout the 
 spinal cord. 
 
 Function of antero-lateral columns of spinal cord; trans- 
 mit motor impulses from the brain to the muscles. 
 
 Functions of the posterior columns; assist in the co-or- 
 dination of muscular movements. 
 
 Functions of the medulla oblongata ; controls the func- 
 tions of insalivation. mastication, deglutition, respiration, 
 circulation, etc. 
 
 Functions of the corpora, quadrigemina ; physical centers 
 for sight. 
 
 Functions of the corpora striata; centers for motion. 
 
 Functions of the optic thalami ; centers for sensation. 
 
 Function of the cerebellum ; center for the co-ordination 
 of muscular movement. 
 
 Function of the cerebrum ; center for intelligence, reason 
 and will. 
 
 Center or articulate language ; 3d frontal convolution on 
 the left side of cerebrum. 
 
 Number of coats to the eye; three; 1st. cornea and 
 sclerotic; 2d, choroid ; 3d, retina. 
 
 Function of iris; regulates the amount of light entering 
 the eve. 
 
KIN U.K. 2 |.3 
 
 Function of crystalline lens ; refracts the rays of light so 
 as to form an image on the retina. 
 
 Function of retina; receives the impressions of light. 
 
 Function of membrana tympani ; receives and transmits 
 waves of sound to internal ear. 
 
 Function of Eustachian tube ; regulates the passage of 
 air into and from the middle ear. 
 
 Function of semicircular canals ; assist in maintaining 
 the equipoise of the body. 
 
 Function of the cochlea ; appreciates the shades and 
 combinations of musical tones. 
 
 Size of human ovum ; T ^ of an inch in diameter.' 
 
 Size of spermatozoa; ^^o °f an i 110 * 1 * n length. 
 
 Function of the placenta ; acts as a respiratory and digest- 
 ive organ for the foetus. 
 
 Duratiou of pregnancy ; 280 days. 
 
?44 
 
 COMPEND OF HUMAN PHYSIOLOGY. 
 
 TABLE OF ARTICULATIONS, MUSCULAR ATTACHMENTS, 
 
 DEVELOPMENT OF CENTERS OF OSSIFICATION, 
 
 ETC., IN " OSTEOLOGY." 
 
 Name 
 Bone 
 
 Occipital 
 
 Parietal . 
 
 Frontal 
 
 Temporal 
 
 Sphenoid 
 
 Ethmoid 
 
 Nasal . . 
 
 of 
 
 Number of 
 Articulations. 
 
 Number of 
 Muscles 
 attached. 
 
 Maxillary Sup 9 
 
 Lachrymal . 4 
 
 Malar 4 
 
 Palate 7 
 
 ipula 
 
 Humerus -; 
 
 Ulna 2 
 
 Radius 4 
 
 Coccyx 
 Innominatum 
 
 Primary 
 
 Developmental 
 
 Cei.ters. 
 
 Turbinated Inf 4 none 
 
 Vomer 6 none 
 
 Maxillary Inf 2 14 
 
 Hyoid none n 
 
 St mum 16 10 
 
 Ribs (12) 24 19 
 
 Clavicle 3 6 
 
 Sc 
 
 Scaphoid ' 5 none 1 
 
 Semilunar 5 none 1 
 
 Cuneiform 3 none 1 
 
 Piriform 1 2 1 
 
 Trapezium 4 3 1 
 
 Trapezoid 4 1 1 
 
 Os Magnum • • 7 1 1 
 
 Unciform 5 2 1 
 
 Metacarpal (5) . . 19 18 10 
 
 Ph .langes (14) 23 20 28 
 
 Vertebrae (24) 72 39 . . . 
 
 Sacrum 4 5 . . . . 
 
 85 
 
 ml 
 
 Femur 3 23 5 
 
 Patella 1 < 
 
 Tibia 3 ic 
 
 Fibula 2 c 
 
 sesamoid 
 3 
 
 Cahis 2 8 
 
 Cuboid 4 1 
 
 Astragalus • • . . 4 . . . . . none 
 
 Scaphoid 4 1 
 
 Int. Cuneiform 4 2 
 
 M d. Cuneiform 4 .... . none 
 
 Ext. Cuneiform 6 2 
 
 Metatarsal (5) 21 13 10 
 
 Ph -langes (14) 23 ....... 23 28 
 
 Malleus 1 3 ? 
 
 Incus 2 .... . 110m 
 
 Stapes 1 
 
 Total in Human Body . 
 
J$*M 
 
Wmr 
 
 Seesaw.