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Tous les autres exemplaires originaux sont filmds en commenpant par la premiere page qui comporte une empreinte d'impression ou d'illustration et en terminant par la dernidre page qui comporte une telle empreinte. Un des symboles suivants apparaitra sur la dernidre image de cha(;ue microfiche, selon le cas: le symbole —^' signifie "A SUIVRE", le symbole V signifie "FIM". Les cartes, planches, tableaux, etc., peuvent dtre filmds 6 des taux de reduction diff^rents. Lorsque le document est trop grand pour §tre reproduit en un seul clich§, il est filmd d partir de Tangle sup6rieur gauche, de gauche 6 droite, et de haut en bas, en prenant le nombre d'images ndcessaire. Les diagrammes suivants illustrent la mdthode. 1 2 3 4 5 6 ^1 Mil inji ii|i iiniiMiaiBi FIRST BOOK ON ANATOMY, PHYSIOLOGY, AND HYGIENE. FOR GRAMMAR SCHOOLS AND FAMILIES WITH EIGHTY-THREE ENGRAVINGS. By CALVIN CUTTER, M.D. AUTHOR OF "ANATOMT, PUTSIOLOOT, AND UYQIENK, FOR C0LLE0E8, A0AI)KMIK8, AN© PAMIUE8;" "SECOND BOOK ON ANATuMf, PlirSIOLOOY, AND UfUIENB, FOR ACADEMIES, BOHOOLS, AND FAMIUE8;" " ANATOJllOAl, OHTUXB PLATES FOB OCliOOIS, KTa BEV18BD STEREOTYPE EDITION. PHILADELPHIA: J. B. LIPPINCOTT & CO. TORONTO: ADAM MILLER, 11 Wellington Street, West. 1871. Bntcrod according to Act of CongreM, in the year 1864. by CALVIN CUTTER, M.D.. Iq the CloTR'i OflBce of the District Court of the DlBtrtct of taaiwachnHOtto. PREFACE Iw presenting this work to the public, th« author would indulge in a few prefatory suggestion*. Education, to be complete, mii?t be not only moral and intellectual, but physical. As the culture of the mind and of the affections is the subject of systematic attention in early life, should not the education of the physical powers be commenced as early ? It will demand no more maturity and thought to understand the reasons for adequate clothing, bathing, *he neces- sity of an erect position in standing and suting, regu- larity in taking food, the supply of pure air to the lungs, (fcc, than to comprehend geographical details or moral truths. Is not a knowledge of the laws upon which health depends, as important to the develop- ment of a vigorous physical constitution, w moral instniction is to the formation of correct moral prin- ciples ? Can any reason be given why both should ♦lot be taught in the school-room? A child should be taught to call each organ by its correct name. No more effort is required to learn the meaning of a proper^ than an improper term. F^or example : a child will pronounce the word as readily, and obtain as correct an idea, if you say lungs^ as if you used the word lights. In preparing tnis work, it has not been deemed necessary to use low, vulgar terms, for the purpose of being understood ^ but such words have been selected VI PREFACE. as good usage sanctions. Should the pupil meet witn any word he does not understand, let him consult his dictionary, as he should do in perusing works upon history, when a similar difficulty occurs. To iFkSure a correct pronunciation of the technical words interspersed with the text, they have been divided into syllables, and the accented syllables des- ignated. An jjrnple Glossary of technical terms luis aiso been appended to the work, to which reference should be made. To the teacher we would suggest the propriety of calling on a pupil of the class, to describe the anatomy of an organ from an anatomical outline plate ; after- wards call upon another to give the physiology of the part, while a third may state the hygiene ; aftei which, the questions at the bottom of the page may be asked promiscuously, and thus the detailed knowl- edge which each pupil porsessea of the subject will be tested. With advanced pupils, it is recommended that the subject be examined in the form of topics. The ques- tions in Italics are designed for this method of reci- tation. For a more full and complete explanation of Anato- my, Physiology, and Hygiene, the pupil is referred to the Author's treatise, of 450 pages, for Colleges, Acade- mies, and Families, or to his second boot:, of 300 pages, for Academies, Schools, and Families. To the instructors of youth, and the patrons of Mucaticn, this work is respectfully j^ubmitted. Warp.en, J/a««., 1852 CONTENTS. 1 GENr.RAL IlEHARKS, 9 S. Anatomt of tub Bones, 11 3. Anatomt of the Bonks, continued, . . .... 16 4. Phtbioloot of thb Bonbs, 21 5. Htoienb of the Bones, 24 6. Anatomy of the Muscles, 27 7. Phtbioloot of the Moscles, . . SO 8. Htoiene of the Muscles, 86 9. Anatomt of the Teeth, 43 »0. Anatomt of the Digestive Okoans , 47 11. Phtsioloot of the Diqestivb Okoans, 63 12. Hygiene of the Digestive Organs, 56 13- Anatomt of the Circclatokt Organs, 62 14. Phtsioloot of th« Circulatort Organs, 67 15. Htgienb of the Circolatort Organs, 70 16. Absorption, 76 17. Secretion, 82 18. Nutrition, 86 19. Anatomt of the Rkspiratort Organs, .... .89 20. Phyj»iologt of the Re: iratort Organs, ... .93 81 Hygiene of thb Kkbpiratory Organs,. . > .98 tftrw^^jr^^v^ WT'w^ TUl 0ONTINT8. Chapter PS|, 22. Animal Hbat, 10« 23. Anatomt o» thb Vocal Oroaks, 110 24. Anatomt of the Ssin, 115 25. PUTSIOLOOT OF THB SkIN, , 119 26. Utoibnb of tub Skist, 122 27. Anatomt of the NKRvor5 Ststbm, 127 28. Fhtsioloot of thb Nervous Stbtkx, 131 29. Htoienb of thb Nebvous Ststbm, 134 80. Senhb of Touch, 138 Sbnbb of Tastb, 139 Sense of Smell, 141 81. Anatomt of thb Organs of Visiok, 143 32. Phtsioloot of the Organs of Vision, 149 S3. Anatov; of the Organs of Hearing, 152 34. Phtsiologt of the Organs of Ebabibo, 155 35. Mbanh of preserving the Ubalth, 158 86 DiRIlOTIONS fob NubSBS, 164 APPE>'DIX, 170 GLOSSABr, 176 INDEl . 181 FIUST BOOK ox ANATOMY, PHYSIOLOGY, AND HYGIENE. CHAPTER I. GENERAL REMARKS. 1. Anatomy is a description of the organs^ or parts o/ a Dody. Examples. Ist. Flowers have roots, stems, and blossoms. These are their organs. 2d. The teeth, stomach, and heart, are some of the organs of the human body.* 2. Physiology is a description of X\\q function^ or use of an organ. Examples. 1st. The roots of flowers suck up water, to make them grow. This is their function. 2d. The stomach, in man, is one of the organs that prepare the food for his growth. This is its function. 3. Anatomy and Physiology are divided into two kinds, namely, Animal au \ Vegetable. , • Where examples are given, let the pupil mention other analog gous ones. I. What is anatomy ? Give examples. 2. What is physiology ? Givo examples. 3. How many kinds of anatomy and physiology are there? 10 OENhRAL REMARKS. 4. Anitnal Anatomy and Physiology are again divided into Human nnd Comparative. 5. Ilunuin Anatomy and Physiology describe iho structure and functions of the organs of man, 6. Comparative Anatomy and Physiology describe the struc- ture and functions of the organs of other animals than man. Examples. As the horse, the monkey, and the whalo. 7. Vegetable Anatomy and Physiology describe the struc- ture and functions of different parts of trees, shrubs, plants, and flowers. 8. ilvGiENE is the art of preserving health, or that depart- ment of medicine which treats of the preservation oiT health. 9. All bodies in nature are divided into Organic and In- organic. Organic bodias include animals and plants. Inor- ganic bodies include earths, metals, and other minerals. 10. All organized bodies have a limited period of life, and this period varies with every species. The duration of some plants is limited to a single summer, as many garden ilowers ; while some trees, as the olive, live many hundred years. Some atiimals live but a short time, while the elephant lives more thun a century. l.\ The life of man is shortened by disease ; but disease is undc the control of fixed laws — laws which we are capable of understanding and obeying. How important, then, is the study of ; thysiology and hygiene ! For how can we expect to obey laws which we do not ui. 'erstand ? 4. How are animal anatomy and physiology divided ? 6. What do human anatomy and physiology describe ? 6. What do comparative anat- omy and physiology describe ? 7. What do vegetable anatomy and physi- ology describe ? 8. What is hygiene ? 9. How are all bodies in nature divided ? What bodies are called organic ? What bodies are called in- organic ? 10. Have all animals and plants a limited period of life ? Doei this period vary with different speiies of animals and plants? Give some exr.mples. 1 1. How is life usually shortened ? Wliy is the study of phyai< •lugy aiid ii) gicne important to every person ? ANATOMY OF THE BONES. 11 CHAPTER II. THE BONES. 12. The b)ne3 are firm and hard, and of a dull white color In all the higher ordors of animals, among which is man, they are in the interic r of the body, while in lobsters, crabs, .fn^e^<^^^*v'''';m!pmfm!^figffifmir 12 ANATOMT, PHYSIOLOGY, AND HYGIENE. Other upon the head, I nuse the bones of the skull in them are softer than in adults. # 17. In each ear are four small bones. They aid in hearing. 18. In the face are fourteen bones. They support the softer parts outside of them. 19. The TRUNK has fifty-four bones — iwenty-four RihSf tw'enty-foui" bones in the Spinal Col'umn^ (back-bone;) four in the Pelvis; the Ster'n^.tPy (breast-bone;) and one at the root of the tongue. 20. All the RIBS are joined to the spinal column. There are twelve on each side. Fig. 2. ^^. Ptg. S. The bones of the npper part of the skuU. 1 , 1, 9, 9, 3, The mturw that joia Oie bones. 21. The seven upper ribs are united in front to the sternum by a yielding substance called car^ti-lage^* (gristle.) The • See paragraj/h 46. 17. What is the use of futures ? How many bonea in each ear ? "What Is their use? J", iiow many bones in the face? 19 — 29. Give the anato my of the hones of the tntnk. 19. How many bones in the trunk ? Name them. 20. To what are all the ribs joined ? How many on each side ? What does fig. 2 represent? 21. How are the first seTen ribs united io tront? ANATOMY OF TFK BOWES. 18 remjining five are not attached, directly, to the sternum. Three are joined to each other by cartilage ; two are not con , fined; hence they are called "floating ribs." 22. The cavity formed by the sternum, ribs, and spinal column, is called the Chest. It contains the heart, iungs, and large blood-vessels. 23. The shape of the chest is conical, or like a sugar-loaf. Fig. 3. The lonii of the chest. ',2,3, The stennim, (breast-bone.) 4, 3, The ■pinal coluirin, (back-bone.) 6, 7, 8, 9, The first rib. 10, The seventh rib. 11, The cartilage of the third rib. 13, The floating ribs. Observation, The lower part of the chest is broader and fuller than the upper part, when it is not made smaller by tight clothing. The next three ? What are the last L^o called ? Why ? Describe flg. S. " 22. How is the chest formed ? What does it contain ? 23. What is th» shape of the chest } How does the lower part of the chest compare in •ixe with the upper? 2 ,,'-■■;. - ,:--:-.zk,'''' M ANATOMY, PHYSIOLOGY, AND HYGIENE 24. llie SPINAL* COLUMN IS composcd of twenty-four pieces of bone. Each piece is called a vert'e'bra. 25. Uetween the pieces, or vertebra;, is a thick piece of car- tilage, which is elastic, or springs like India-rubber. This not only unites the vertebiTc, but pernnits them to move in diflerent ways. 26. There is an opening in each vertebra. By a union of these openings, a canal is formed the whole length of the spinal column in which the spinal cord (pith of the back-bone) is placed. Fig. 4. Fig. 5. Fig 4. The form of a vertebra of iho neck. 1, The main portion of Ite bona. 2, 'I'he spinal canal, in which tJie spinal cord is placed. 4, 5, 7, 8, Points, < projto liuns of ihe vertebra. r=3, 5. 1, The cartilage that c mnects the vertcbree. 3, 4, 5, 6, Points, r pro- jections of the vertebra. 7, The Hpinal canal. Observation. A good idea of the structure of the vertehraj may be obtained, by examining the spinal column of a domestic animal, as the dog, cat, or pig. • From the Latin spi'na, a thorn ; so called from the points of tfe.» rertebrae that are felt beneath the skin. 24. How many pieces of bone in the spinal column ? "What is each piece called ? 2.5. What is placed between the vernebrie ? Give its use. 26. How is the spinal canal formed, and what does it contain ? Describe fig. 4. Describe fig 5. How may an idea of the structure of th* Terte* OIK be obtained 2 ANATOMY OF THE BONES 1» 27. I'he spinal column is a very curious and perfect piece of mechanical art. By its structure, great strength and suf- fijiient movement or tiexibility are combined. The vertebrfla are so firmly joined together, that dislocation of tliem, without fracture, is very rare. 28. The PELVIS is composed of four bones. They are so arranged as to form a bony basin. Tlie spinal column testa on these bones, and they also serve to support the lower extremities. Fig. 6. Pig. 6. 1, 1, The hip-bones. 2, The sacrum, wynm which the Hpinal coiumn re Its. 3, Tlie extremity of the spinal column, named the coc'cyz. 4, 4, The cavitiea for the head of the tliigh bone. 29. In the sides of these bones is a deep, round cavity, called a-ce-tabu-lum, in which the head of the thigh-bone ia placed. 27. What is said of the structure of the spinal column ? 28. Of how many bones is thr pelvis composed ? What is their use ? Describe fig. C Hi. Wiiat is found in the bidea of these bones ? 16 ANATOMY, PHYSIOLOGY, AND HYOIENB. CHAPTER III. ANATOMY OF THE BONES, CONTINUED. 30 The upper extremities contain sixty-four bones — the Scap'ii-la^ (shoulder-blade;) the Clav'i-ch^ (collar- bone;) and the bones of the Arm^ Fore-arm^ Wrist^ and Hand. 31. The SCAPULA is a broad, irregular bone, situated upon the upper and back part of the chest. 32. The CLAVICLE is a thin bone at the base of the neck. It IS joined at one extremity to the sternum, at the other to the scapula. Observation. The use of the clavicle is to keep the arms from sliding toward the breast. Children should frequently throw their arms backward, as t'^ s exercise would tend to increase the length of this bone, am nlso to enlarge the chest. 33. The ARM is formed of a su.^ > bone, called the hu'' mer-us. 34. The FORE-ARM is formed of two bones — the w/'nrt, on the inner side, and the ra'di-us., on the outside, (the side on which the thumb is placed.) By a beautiful arrangement of these bones, the hand is made to rotate^ or turn, permitting ita complicated and varied movements. 35. The WRIST is formed of eight irregular bones. They move but little upon each other. 36. The HAND consists of nineteen bones — five in the palm, and fourteen bones in the fingers and thumb. * 30 — 37. Give the anatomy of the hones of ihc upper extremities. 30. Name the bones of the upper extremities. 31. Describe the Sv?apula. 32. "Where is the clavicle situated ? \Vliat is the use of the clavicle ? 33. How ia the arm formed ? 34. The fore-arm ? 35. How many bones in the wrist ? 86. How many bores in the hand ? ANATOMY OP THE BONES. 17 37. Kach finger is formed of thr^e bones of diflerent lengths the thumb has but two. Proofs of a designing Creator aro nowhere more manifest than in the simple but wonderful structure and adaptation of the human hand. 38. The LOWER extremities contain sixty bones — the Fe'mur^ (thigh-bone ;) the Pa-tel'la^ (knee-pan ;) the Tib'i-a (shin-bone;) \\ie Fib'u-la^ (small bone of the leg;) and the bones of the Foot. 39. The FEMUR is the longest bone of the body. It sup- ports the weight of the head, trunk, and upper extremities. Fig. 7. Fig. 8. Fig. 7. V, The nlna. R, The radiui. s, L, c, P, U, M, T, T, The eight bones «l the wrist. 1> 1, 1, 1, 1, The five bones of the pjilm of the hand. Fig. 8. 10, 10, 10, Tile bones of the palm of the hand 11, 13, 13, The bonea of (he fingers. 14, 15, The bones of the thumb. 40. The TIBIA and the fibula are situated between the knee and ankle. 37. What is said of the bones of the fingers and thumn ? 38 — 41. Qiv the anatomy of the bonea of the lower extremities. 38. Name th« oonfs of the liwer extremities. 39. "What is said of the femur? Describe fig. 7. anUe? Fig. 8 40. What bones between the knee and J8 ANATOMY, PHYSIOLOGY, AND HYGIENE. 41. Th« FOOT is formed of twenty-six bones --seven in the instep ; five in the middle of the foot; and fourteen toe-Dones. Observation. Tlie bones of the foot ore so united as to give it the form of an arch, — convex on its upper surface, and con- cave on the lower surface. Fig. 9. Fig. 9. A view of the upper surfnce of the Ijones of the foot. 1, 2, 3, 4,5, 8, T 8, The bones of the instep. 9, 9, 9, Tlie boncfl of the middle of the foot. 10, 11, Th« bonea of the great toe. 12, 13, 14, The boaea of the siiiull toea Fig. 10 P (?. 10. A Bide view of the bones of the foot, showing its arched form. The arch rests upon the htel behind, Rnd the baU of the toes in front. I, Tnt lower i«rt of the tibia. 2, 3, 4, 5, Runes of the instep. 6, A bone of the middle of the foot. 7, 8, The bones of tlie great toe. ♦ 42. The bones consist of animal matter, (jelly,) and earthy matter, (phosphate and carbonate of lime.) 41. How many bones in the foit, and name them ? What is the form 3f the foot? Describe fig. 9. Fig. 10. 42. Of what are the bonec •omposed? » ^ ^, :,'„ ana:omy op the bones. 19 43. To show the cinitnal without the eurthy matter of the bones, immerse a slender bone tor a few days in a weak aciu, (one part muriatic acid and six parts water,) and it can then be bent in any direction. 44. To show the earthy without the animal matter, bum a bone in a clear fire for about fifteen minutes, and it becomet white and brittle. 45. The JOINTS form an interesting part of the body. They are composed of the extremities of two or more bones, Car'li- ingcc^ '. Joint more frequently dislocated than any other in th>^ body i |»P»v8'Ol,OGY OF THE BONES. Fig. 17. 2f^ '■W P»g 17. 1,1, The spinal column. 2, TheFkuIl. 3, The lower jaw. 4, The sternam. \ The libs. 6,G, The carMlagCH of the ribs. 7, Tl,e clavicle. 8, The humerus. 9, Th« rhoulder-JoinC 10, The radius. 11, The ulna. Vi, The elbow-joint 13, The wriat. U, The hand. 15, The luuinch-bone. IG, The sacrum. 17, The hip-joint. 18, The thigh-bone. 19, The patfll.i. 20, The knee-joint. 21, The fibula. 22, The tibia. 23, The ankle-joint. 24, The foot 2.";, 2ti, The lignnients of the clavicle, Rtemum, and ribs. 27, 28, 29, The ligaments of the shoulder, elbow, and wrist. 30, The larfe Kitery of the arm. 31, The ll^ainentsof the hi|>-joint. 'M, The largo bl(M>d-VMwbior the fhigh. 33, Thearterj'ofthelei^. 34, 35, 3(3, The iigauienlsufthe patella, kne«, and ankla. A'd(£. Let the pupil, in form of topics, review the anatomy and physiology of Jm ^nes from fig. 17 or from anatomical outline plateb 1 and 3. 14 ANATOMY, PHYSIOLOGY. ANU BTOIXNX. CHAPTER V. HYGIENE OF THE BONES. 67. The hones require exercise to make them healthy. By use they arc iiicr ased in size and strength to a limited extent, while inaction or disease weakens them. Exercise favors the deposition of the substances of which they are composed. 58. The exercise or labor should he adapted to the condition of the hones. The bones of a child contain more of the animal than the earthy matter, and are consequently weak ; though the child is able to exercise, its bones are not adapted to severe toil. On the other hand, the bones of the aged man contain more earthy than animal matter. This causes them to be brit- tle and unfit for labor. But in middle age, the proportions of animal and earthy matter are, usually, such as to give the proper degree of flexibility and strength for labor, with little liab lity to injury. Ohservation. The difference in the structure of the bonea at different ages may be seen, by comparing the rib of a calf or lamb, with the rib of an ox or sheep. 59. The clothing should he loosely worn. The ribs and bones of the spmal column are soft and yielding in childhuod. A small amount of pressure on the walls of the trunk will lessen the size of the chest, and thus injure the lungs, stomach, and heart 60. In sittings the feet of the child should he supported. If 67—63. Give the hygiene of the bone*. 67. What effect has exerciw upon the bones ? 68. Give the reasons why the amount of labor should be adapted to the condition of the bones. How can the difference in the structure of the bones at different ages be illustrated ? 69. Give a reason why the clothing should be loosely worn. 60. Why should the feet of ihildren, when sitting, be supported ? »;:.*;«. ;ii*; nVGIENK OF THE BONES. 35 ihe stool IS so hi^h as not to permit the feet to rest upon the Hoor, the weight of the limbs below the luuie luiiy cause the flexible hone of the thi^fh to becntne curved. When the feet are not supported, the child is inclined to lean forward, contract- ing an injurious and ungraceful position. Observation. The scats in school-rooms should not only be of such height as to enable the pupil to rest the feel on tlio floor, but they should have properly-constructed backs. Fig. 19. Fig. 18. The position ossuined when the leat ia of proper height, and the feet buppiirtcd. Fig. 19. The position a child naturally assumes when Uie seat ia so high tliat Mm feet are not 8u;)ported. 61. Children should stand and sit erect. This position tends '.o keep the spinal column erect and healthy. When a slight cur/ature of the spine exists, it can be improved by walking with a book, or a heavier weight, upon the top of the head ; tq Should seats in a school-room have backs ? 61. Wliy should childrea •land and sit erect ? a 26 ANATOMY, PHYSIOLOGY, AND HYGIENE. ba!7*iice which, the spine must be nearly erect. Thosfi people that carry their burdens upon their heads se'dom have crooked spines. * 62. Pupils, while writing, drawing, and sometimes while studying, frequently incline the spinal column to one side, in order to accommodate themselves to the desks at which they are seated. This position elevates one shoulder, while i t de- presses the other. ; , Fig. 20. Fig. ^X A representation of . deformed spinal column. A well-Armed spinal column has three curves, two forward und one bucliward, (2, 2, 2, fig 25,} but no lateral curvature, (1, 1, Ag. 17.) 63. One shoulder may be thus elevated for a short time, and no injurious results follow, prrivided care is taken not to keep it in the raised position too long, or if the opposite shoulder is elevated for the same period of time. What is the effect of carrying biirdens upon the head ? 62. What is tht effect of pupils using desks that are too Itigh or improperly constructed 6S. How can one shoulder b« elevated, Aud *o injurious results follow ? ANATOMY OF THE MUSCIES. 27 CHAPTER VI THE MTJSCLES. « 64. All the great motions of the body are caused by the movement of some of the bones which form the framework of the body ; but these, independently of themselves, have not llie power of motion, and only change their position through the action of other organs attached to them, which, by contracting, or shrinking, draw the bones after ihem. In some of the slight movements, as the winking of the eye, no bones are displaced, or moved. These movmg, contro 'ting organs are the Mus'ch^y (lean meat) "* ANATOMY OF THE MUSCLES. 65. A MUSCLE is composed of many little strings, called fibres. Some of these fibres run in straight lines ; others spread like a fan ; while some are inclined like the feathery part of a quill. (Fig. 21.) 66. Toward the extremities of a muscle the fibres unite, and form a substance of a whitish color, harder and tougher than the muscle. This is called ten'don^ (cord, sinew.) Observation. TI t pupil can examine a piece of boiled beef, or the leg of a fowl, and -^ee the structure of the fibres and tendons of a muscle, with the attachment of the tendons tc the bones. 67. Tendons have various shapes. Sonie*imes tt.'iy are 94. Ilovy are all the great motions of the body produced ? What are these moving, contracting organs called ? 65 — 72. Give the structure of the muaclea. 65. Of what is a muscle composed ? 66. What in a tendon ? How can the structure of a muscle be shown ? 67. Wliat is the shape ol tendons ? m ANATOMY, PHYSIOLOGY, AND HYGIENE. long, slender strings; sometimes they are short and thck again, in some situations, they are thin and broad. Thej serve to fasten the muscles to the bones, or to each other. Observation. In some instances, the synovial membrane, which forms the sheath of the tendons, is ruptured, and the synovial fluid escapes. This forms a tumor, called a gan'gli-on, (weeping sinew.) It is called a wind-gall when on the limbs of a horse. 68. in tha description of a muscle, its attachments are ex- piessbd by the terms origin and instrlion. The term origin is general Jy applied to the more fixed or centml attachment, or to the points toward which motion is directed ; while insertion is assigned to the more movable point, or to that most distant from the centre. The middle, fleshy portion, is called the " belly,'* or swell. Fig. 21. Pig. 21. I, Represents the fibres of a muscle running in straight lines. S, Th« Ibn-shaped fibres. 3, 4, Fibres inclined like the plumes of a quill, t, (, Tendons a* the extremities of the muscle, L 69. In some parts of the body, there is but one layer of muscle over the bones ; in other parts, there are five or six How are the tumors formed, called weeping sinews ? 68. How are the attachments of muscles expressed ? What is the middle portion called ^ 69. How many layers of muscles aie there around the bones ? ,p--.-Ty,».-7jr-T--i;'-'^r>-^yv- -Tr.-,. 1.7 t ..y-^r-, "■■■.■--•■'; v ,•,> - ' ■ ''W^Jij .••■:::^.\ AN.? rOMY OF THE MUSCLES. 95 layers, ona muscle being placed over another. They are sepa- rated by a tiiin, whitish membrane, ciUlcd fas'ci-a. Observation. An instance is seen in the membrane which envelops a leg of beef, and which is observed on the edges cf Pi slice when it is cut for broiling. 70. In general, the muscles form about the bones two layeiTJ, calleo the superficial^ or external muscles ; and the deep-seated^ or those nearest the bone. 71. There are more than four hundred muscles in the human body. To these, and a yellow substance, called fat^ that surrounds and fills the spaces in the muscles, the child and youth are indebted for the roundness and hearty of their limbs. Observation. When we are sick, and cannot take food, the / is {*;d with ihis fat. The removal of it into the blood causes the sunken cheek, hollow eye, and prominent appear- ance of the bones, after a severe sickness. 72. When we look at this "harp of thousand strings," and notice the varied, rapid, complicated, yet accurate movements it performs in a single day, our thoughts are lost in wonder, in contemplating this superb and mtricate machine, framed and finished by the divine Architect How are they separated from each othor? Give an instance where thia membrane may be seen. 70. How many lav«»rs of Tuscles generally around the bones, and M-hat are they called ? 71. How m»nv n)i|iu>l<>s in the hu man body? "W* y are the limbs of a child nu a rntind and full thar ws aged ptTSOo'f ? How is the body nourished whca wc ctioTiot t«k<« toodk * W ANATOMY PnySIOLOGY, AND HYGIENE. CHAPTER VII. PHYSIOLOGY OF THE MUSCLES. 73. Every motion of the body is made by the contraction of the fibres of the muscles ; from the awkward movement of the boy's first efibrt at penmanship, to the delicate and graceful sweeps of the pianist ; from the firm, the stately tread of the soldier, to the light, fairy-like step of the danseuse. Illustration. The muscles ami tendons are to the bones what the ropes are to the sails and yards of a sh'p. By their action, the direction of the sails and yards is chanj^ed. So, by the action of the muscles, the position of the bones of the body is changed. 74. Each fibre of the several muscles receives from the brain, through the nervous filament appropriated to it, a certaiu influence called nervoiis fluid ^ or stimuhis. It is this that in- duces contraction, while the suspension of this stimulus causes relaxation of the fibres. 75. Muscles remain contracted but a short time ; then they relax, or lengthen, which is their rest. When the muscles are in a state of contraction, they are full, hard, and more prom- inent than when relaxed. 76. The alternate contraction and relaxation of the muscles may be shown by the following experiment: — Experiment. Clasp the fore-arm about three inches below the elbow, then open and shut the fingers rapidly, and the 73 — 99. Give the physiology of the miiscles. 73. How is every motion of the body produced ? 74. With what is each muscular fibre supplied ^ What effect has this stimulus on the muscles ? 75. Do muscles remain crntracted a long time ? What is their appearance when in a state of con- traction ? 76. How can the aU«rnate contraction and relaxation of the muscles be shown ? ^-V'-XP'l rnvsioLOGY of titk muscles. 81 Bwelling and relaxation of tlie muscles on the opposite sides of *he arms, alternately with each other, will be felt correspond ing with the movement of the fingers. While the fingers are bending, the nside muscles swell and the outside ones become flaccid ; and, while the fingers are extending, the inside mus- cles relax and the outside ones swell. The altornate swelling and relaxation of opposing muscles may be felt in all the move- ments of the limbs. Fig. 22. 2 4 t rejrrenentation of the manner in which all nf the joints of the body are m6V«d. Fig. 22, 1, The bone of the arm above the elbow. 2, One of the bones below fh« ilbow. 3, The muscle that bends tlie elbow. This muscle is united, by » tendon, to the bone below the elbow, (4 ;) at llie other extremity, to the bone above the elbow, (5.) 6, The muscle that extends the elbow. 7, Up attachment to tlie point of the eJbow. 8, A weight in the hand, to be raised. ' .le central part of the musc!e (3) contracts, and its two ends are brought nearer together. The bones beh»w the elbow are brought to the lines shown by 9, 10, II. The weight is raised in the direction of the curved line. When the muscle (6) contracts, the muscle (3) relaxes, and the el- bow is extended. 77. The eyebrows are elevated, or raised by the contraction of the muscles on the forehead, 1, fig. 23. 78. The eyes ar^ closed by the contraction of the muscles that surround them, 2, fig. 23. Explain 65?. 22. Note. Let the anatomy and physiology of the muscular system be re viewed, in form of topics, from figs. 23, 24, or from the outline anatomicft« plates 3 and 4 ji M (ij'-pi ■■(■iiiiwi iijii.mi'.v f ! I. 82 ATOMY, PHYSIOLOGY, AND HYGIENE. 79. The upper lip is elevated by the contraction of the mus- cles, 3, 4, 5, 6, fig. 23. 80. The mouth is closed by the contraction of a muscle that surrounds it, 7, fig. 23. 81. The lower lip is drawn down, or depressed, by the con traction of muscles on the lower part of the face, 8, fig. 23. 82. The head is bent forward, as in nodding, by the contrac- tion of muscles on the front part of the neck, 9, fig. 23.- 83. The chin is raised, and the head is brought erect by the contraction of muscles on the back part of the neck, 5, 6, fig. 24. 84. I'he body is bent forward, and the ribs brought down, by the contraction of muscles on the front and lower part of the trunk, 22, 23, fig. 23. 85. The spinal column is kept erect by the muscles at the lower and back part of the trunk, 24, 25, 26, fig. 24. 86. The shoulders are brought forward by the muscles upon the upper and (ront part of the chest, 11, fig. 23. 87. I'he shoulders are brought back by the contraction of the muscles upon the upper and back part of tlie chest, 7, fig. 24. 88. The arm is elevated by a muscle upon the shoulder, 10, fig. 23 ; and 8, fig. 24. 89. The arm is brought to the side by muscles, 11, fig. 23; and 24, fig. 24 90. The elbow is bent by the contraction of the muscles on the upper and front side of the arm, 14, fig. 23. 91. The elbow is extended by a muscle on the back part of /he arm, 10, fig. 24. 92. The wrist and fingers are bent by the muscles on the front part of the arm, below the elbow, 16, 18, fig. 23. 93. The muscles on the back part of the arm, below the elbow, extend the wrist and fingers, 21, 22, 23, fig. 24. 94. The muscles that bend the lower limbs, at the hip, are situated at the lower and front part of the trunk, and the upper and front part of the thigh, 25, 26, 27, 28, fig. 23. PHYSIOLOGY OF THE MUSCLES. 38 95. The lower limbs are extended at the hips by the muscles on the lower and back part of the trunk, and the uppei and back part of the thigh, 27, 2b, fig. 24. 96. The muscles upon the front part of the thigh extend the leg at the knee, 29, 30, fig. 23. 97. The knee is bent by the muscles upon the back part of the thigh, 29, 30, fig. 24. 98. The muscles upon the fore part of the leg, below the knee, bend the foot at the ankle, and extend the toes, 34, 35, 36, fig. 23. 99. The muscles upon the back part of the leg, below the knee, extend the foot at the ankle, and bend the toes, 31, 32 33, fig. 24. Observation. It would be a profitable exercise for pupils to press their fingers upon prominent muscles, and, at the same time, vigorously contract them, not only to learn their situations, but their use ; as the one that bends the arm, 14, fig. 23. [Fig. 23. A front view of the muscles of the body. 1, The frontal swells of the occipito-frontalis. 3, The orbicularis palpebrarum. 3, The levator labii superioria alteque nasi. 4, The i^ygomaticua major. 5, The zygoniaticus minor. 6, The mosseter. 7, The orbicularis oris. 8, The depressor labii Inferioris. 9, I'he {ilatysma myoides. 10, The deltoid. 11, The pectornlis major. 13, Thb latissimus dursi 13, The serratus major anticus. 14, The biceps flexor cubiti. 15, The triceps ex- tensor cubiti. 16, The supinator radii longus. 17, The pronator radii um cm. 18, The extensor carpi radialis longior. 19, The extensor oasis metacarpi pollicis. 30, The nnnular ligament 31, The palmar fascia. 33, The obliquuit externus abdominis. 23, The linea alba. 24, The tensor vagine femoris. 26, The psoas magnua 27, The abductor longus. 38, The sartorius. 39, The rectus femoris. 30, The vastus externus. 31, The vastus Internus. 32, The tendo patella;. 33, The gas- trocnemius. 34, The tibialis auticus. 35, The tibia. 36, The tendons of the ex tensor communis. Fig. 24. A back view of the muscles of the body. 1, The temporalis. 2, The occipito-frontalis. 3, The complexus. 4, The splenius. 5, The masseter. 6, Tli* ■tcrno^^leido mastoideus. 7, The trapezius. 8, The deltoid. 9, The infra spinatus. ;0, The triceps extensor. 11, The teres minor. 12, The teres major. 13, The tendinous portion of the triceps. 14, The anterior edge of the triceps. 15, The supinator radii longus. 16, The pronator radii teres. 17, The extensor conuniinit digitorum. 18, The extensor oesis metacarpi pollicis. 19, The extensor comniunia •ligitorum tendons. 20, The olecranon and in.sertion of the triceps. 21, The exten* ■or tarpi ulnads. 22, The auricularis. 23, The extensor communis. 24, The Litis ■imus dcrsi. 2.% Its tendinous origin. 26, Tlie obliquus externus. 27, The ghitei'j medius. 28, The gluteus magnus. 29, The biceps flexor cruris. 30, Tne semi-tea dinoflus. 31, 32, The gastrocnemiua. 33, Tlie tendo- Achillis.] y* --.•i^^'M '■ • 34 ANATOMY, niYSlOLOGY, ANH HYGIENB. Fig. 23. PHYSIOLOGY OF THE MITSCLBS. 35 Fig. 24. 86 ANATOMY, PHYSIOLOGY, 4Nr> UtulEftm CHAPTER VIII. HYGIENE OF THE MUSCLES. 100. Tlie muscles should he used and then rested. Tih* will increase their size and strength, by increasing the flow oi blood to the parts called into action A muscle should not be used too long, or remain at rest too long ; both are alik« injurious. Illustrations. 1st The blacksmith uses and rests the mus- cles of his arm when striking upon the anvil. They not only become large, but very firm and hard. 2d. The student uses the muscles of the arm but little, in holding his books and pen ; they are not only small, but soft. 3d. Let the student leave his books, and wield an iron sledge, and the muscles of his arm will increase in size and firmness. On the other hand, let the blacksmith assume the student's vocation, and the muscles of his arm will become fioft and less firm. 101. Exercise should he regular and frequent. The sys- tem needs this means of invigoration as regularly as it does new supplies of food. It is no more correct that we devote several days to a proper action of the muscles, and then spend one day inactively, than it is to take a proper amount of food for several days, and then wi'/ iw this supply for a day. 102. Every part of the muscular system should have its appropriate share of exercise. Some employments call into 100 — 118. Give the hygiene of the muscles. 100. Why should every mu8 cle be used ? What is injurious to muscles ? How is the effect of using muscles illustrated? 101. Why should the exercise of the muscles b« regular and frequent ? 102. What employments and amusements are b«st CDr ths health ? Il AYGIENE OF THE MUSCLES. 89 exercise the muscles of the upper limbs, as shoe-making ; others the muscles of the lower limbs; while some the muscles of l)oth upper and lower limbs, with those of the trunk, as farming. Those trades and kinds of exercise are most salutary, in which all the muscles have their due propoition of action, as this tendi to develop and strengthen them equally. 103. The proper time for exercise should be observed. This is modified by many circumstances. As a general rule, the morning, when the air is pure and the ground dry, is better than the evening; for then, the powers of the body are greatest We should avoid severe exercise and labor immediately before and after eating a full meal, for the energies of the system are then required to perform the digestive function. 104. Tlie muscles should be used in pure air. The purei the air we breathe, the longer can the muscles be used in labor, walking, or sitting, without fatigue and injury ; hence the bene- fit derived in thoroughly ventilating all inhabited rooms. Observation. It is a common remark that sick persons will sit up longer when riding in a carrian;e, than in an easy I chair in the room where they have Inn sick. In the one instance, they breathe pure air, in th other, usually, a con- fined, impure air. 105. The muscles should be exercised in the light. Light, particularly that of the sun, exercises as great an influence on I man as it does on plants. Both require the stimulus of this I agent. Students should take their exercise during the day, ■|i rather than in the evening, and the farmer and the mechanic ;:| should avoid night toil, as it is much more exhausting than the I same eflbrt during daylight. I Illustrations. Plants that grow in the ^hade, as under a I board, are of lighter color and more feeble than those that are -^ Why? 103. What time, in general, is best for exercise? What should be ^ avoided ? 104. Why should the muscles be used in pure air ? Give obser- 3. vation. 105. Why should students take their exercise in the davtime ? M What should farmers and mechanics avoid ? Why ? How ia the iuftuenct ^ of Bclar light illustrated ? p 4 1 88 ANATOMY, PnYSIOLOGV, AND IIVGIENE exposed to tho lig it of the sun. Persons that dwell in dark rooms, nro paler and less vigorous than those who inhabit apartments well lighted, and exposed to solar light. 106. Every muscle should move freely. Compression by any means, lessens the size and strength of the muscle. Illustration. Let a surgeon bandage a limb for some weeks, when a bone is broken, and when the bandage is removed, the limb will be found smaller than when the accident occurred. The compression by close dresses produces similar eflecis upon the muscles of the body. 107. The state of the mind affeclb musailar contraction. A person who is "heerful and happy will do more work, and with less fatigue, than one who is peevish and unhappy. Illustration. A sportsman will pursue his game miles with- out fatigue, while his attendant, not having any mental stimu- us, will become weary. 108. The erect attitude lessens the exhaustion of the muscles. A person will stand longer, walk farther, and do more work, wh«)n erect, than in a stooping posture; because the muscles of the back, in stooping, are in a state of tension, or stretching, to keep the head and trunk from falling forward. In the erect position, the head and trunk are nicely balanced and supported by the boncfc of tho spinal column, and the muscles of the back are called but slightly into action. Experiment. Hold in each hand a pail of water, or equai weights, in a stooping posture, as long as it can be done with- out much suffering and injury. Again, when the musculai pain has ceased, hold the same weights, for the same length of time, in an erect posture, and note the difTerence in the fatigue of the muscles. Ohsewation. The attitude of children in standing has been 106. Why should every muscle more freely ? How is the effect of com- pression illustrated ? 107- Does the mind affect the action of the muscles ? How is this illustrated ? 108. "What attitude lessens the exhaustion of thf muscles ? Why ? How is the effect of position shown by experiment I What is said respecting the attitude of child en ? HTOTENE OF THE MUSCLES. »9 mur.h neglected ooth by parents and tcncliers. Let a child acquire the habit of inclining his head ai d shoulders, and the chest wi.l become contracted, the muscles of the back enfeebled, and the deformity thus acquired will progress to advanced age Fig. 25. Fig. 26 Pig. 25. 1, A perpendicular line from the centre of the feet to the upper extrem- ity of the opiiial column, where the head rests. 2, 2,2, The spinal coiamn, with its three natural turves. Here the head nnd body arc Imlnnccd upon the spinni column and jointib if the lower extremities, so that the muscles are not kept in n state of tcn- i.)n. This erect position of the bmly and head is rlways accxnpanied with straight lower limbs. Fig 26. 1, A perpendicular line from the centre of the feet. 2, Represents th; un natural curved spina column and its relative position to the perpendicular, (1.) The lower limbs are seen curved at the knee, and the body is stooping forward. While ■landing in this position, the muscles nf the lower limbs and back are in conl.nued tension, which exhauat3 and weakens them. What is represented by figs. 25 and 26 ? 40 ANATOMY, PHYSIOLOGY, AND HYGIENE 109. Wfiile studying^ drawing, writing, and sewing, the lody should be kept erect. This attitude favors a healthy action of the various organs of the body, and conduces to beauty and symmetry of form. On the contrary, narrow chests, " hollow stomachs," " round shoulders," and ill health, follow a viola- tion of this rule. Fig. 27 Fig. 28. Fig. 97. An improper, but not an unusual poaition in Bitting, Fig. St>. A proper position in sitting. 1 10. Muscles should be gradually called into action. When the muscular system has been in a state of rest, \i should not suddenly be called into vigorous action. On arising from a be 1, lounge, or chair, the first movements of the limbs should be slow, and then, if necessary, gradually increased. 109. What is one cause of narrow chests and round shoulders ? 110. "What caution is given in using the rausclci when they have been iv a sUte of rest ? What does fig. 27 show ? Fig. 28 ? -"V^ HYGIENE OF THE MUSCLES. 41 Observation. If a man lias a certain amount of work to be performed in nine hours, and his muscles have been in a state of rest, he will do it with less fatigue by performing half the amount of the labor in five hours, a d the remainder in four hours. The same principle should be regarded in driving horses and other beasts of burden. 111. Muscles should be rested gradually, when they have been vigorously used. If a person has been making great muscular exertion in cutting wood, or any other employment, instead of sitting down to rest, he should continue muscular action by some moderate labor, or amusement. 112. When the skin is covered with perspiration, (sweat,) from muscular action, avoid sitting down " to cool " in a current of air ; rather put on more clothing, and continue to exercise moderately. 1 13. In cases when severe action of the muscles has been endured, bathing and rubbing the skin over the joints that have been used, are of much importance. This will prevei.t soreness of the muscles and stiffness of the joints. 114. In labor, or exercise, the muscles should be relaxed. In walking, dancing, and learning to write, there will be Jess fatigue, and the inovements will be more graceful, when the muscles are slightly relaxed, than when rigidly contracted. The same principle applies to mo^t of the mechanical em- ployments. Experiments. Attempt to bow with the muscles of the limbs and trunk rigid, and there will be a stiff bending of the body only at the hip-joint. On the other hand, attempt to bow with the muscles moderately relaxed ; the ankle, the ku e, and Give observation. Should the same principle be observed in driving horses ? Ill ^low should muscles be rested when they have been vigor- ously used .•' 112. When the skin is covered with perspiration from muscu- lar action, how should it be " cooled" ? 113. How can .screncss of the mus- cles be prevented ? 114. In what state should be the muscles of the arm in writing or performing most employments ? How is this principle shown by ezperimente ! 4» 12 ANATO^tfT, PHYSIOLOGY, AND HYGIENE. the hip-jomt will slightly bend, accompanied with an easy and graceful curve of the body. 115. When riding in cars and coaches, the system will not suffer so severely from the jar if the muscles are slightly relaxed. When riding Dver uneven places in roads, rising slightly upon the feet diminishes the shock occasioned by the sudden notion of the carriage. The muscles, under such circumstances, are to the body what elastic springs are to a carriage. 116. In jumping or falling from a carriage, or any height, the shock to the organs of the body may be obviated in the three following ways. 1st. Let the muscles be relaxed, not rigid. 2d. Let the limbs be bent at the ankle, knee, and hips ; the head should be thrown slightly forward, with the trunk a little stooping. 3d. Fall upon the toes, not the heel. 1 17. Repetition of muscular action is necessary. To render the action of the muscles complete and effective, they must be called into action repeatedly and at proper intervals. This education must be continued until not only each muscle, but every fibre of the muscle, is fully under tlie control of tlie will. In this way, persons become expert penmen, singers, and skilful in every emplojment. 1 18. In training the muscles for effective action, it is very important that correct movements be adopted at the com- mencement. If this is neglected, much power will be lost. 115. What suggestion when riding in cars or coaches ? 116. In jumpijtg itam a carriage, in how many ways can the shock to the organs of the body be obviated? Give the 1st. The 2d. The 3d. 117. How do persons be- come expert penmen, singers, or skilful in any employment ? 118. What is necessary m trailing the muscles for effective action i ANATOMY OF THE TEETH. 48 CHAPTER IX. ANATOMY OF THE TEETH. 119. The teeth aio nrmly fixed in the sockets of the upper and lower jaw. The first set, which appear in infancy, is called tem'po-ra-ry^ or milk-teeth. They are twenty in num- ber; ten in each jaw. Fig. 29. Fig. S9. The permanent teeth of the upper and !ower Jaw. a, b. The incisora. c, The cuspi.^s. d, e, The bicuspids. /, g, The molars, (double teeth.) A, The wisdom teeth. 120. Between six and fourteen years of age, the temporary teeth are removed, and the second set nppeare, called per'ma- nent teeth. They number thirty-two, sixteen in each jaw. 121. The four front teeth in each jav;^ are called in-ci'sors^ 119 — 123. Give the anatomy of the teeth. 119. In what are the teeth placed ? What is the first set called ? How many in number ? Describe feg. 29. 120. "Wlion are these teeth removed ? What is the second set called ? How many in each j w ? 121. What are the teeth in front called ? 44 ANATOMY, PIIYSIOLOGY, AND HYGIENE. (cutting teeth ;) the next toofh on each side, the cus'pid^ (eye tooth ;) the next two, bi-cus'pids, (small grinders ;) the next two mo'lars, (grinders.) The last one on eacli side of the jaw, la called a wisdom tooth., because it does not appear until a person is about twenty years old. 122. Each tooth is divided into two parts; iiannely, crown and root. The crown is that part which protrudes fronn the jaw-bone and gum. The root, or "fang," is placed in the sockets of the jaw. Fig. 30. Fig. 31. Fig. 30. A side view of tlie body and enamel of a front tooth. Fig. 31. A side view of a molar tooth. 1, The enamel. 2, The body of the. tooth 3, Theca.ity in the crown of the tooth. 4, A nerve that spreads in the pulp of the tooth. 5, An artery that ramifies in tlie pulp of tlie tooth. 123. The crowns of the teeth are covered with a very hard substance, called en-am'el. The roots consist of bony matter. • PHYSIOLOGY OF THE TEETH. 124. The use of the teeth is twofold. 1st. By a cutting and grinding movement, they divide the masses of food into The next ? The next two ? Those next the bicuspids ? The last that appear in thf jaw ? 122. How is each tooth divided ? "Which part of the tooth is the crown ? Which the root ? 123. "With what ait the crowns Df the teeth covered ? Of what docs the root consist ? Describe fig. 31. 424 — 126. Give ih£ physiology of the teeth. 124. What is one use of the teeth } HYGIENE OF THE TEETH. 45 smaller pieces, so tliat they are more easily and readily changed in the stomach. 125. 2d. The teeth aid us in spr 'cing with distinctness certain letters and word.-:. An individual who has lost his front teeth cannot pronounce distinctly certain letters, called dental, 126. The teeth also give beauty to the lower part of the face. When they are removed, the lips and cheeks sink in, as is frequently seen in old age. Con.scfiuently, those sijiiple observances that tend to the preservation of the teeth, are ol practical interest to all persons. HYGIENE OF THE TEgTH. 127. To preserve the teeth^ they must be kept clean. After eating food, they should be cleaned with a brush and water, or rubbed with a piece of soft flannel, to prevent the tartar col- lecting, and to remove the pieces of food that rnay have lodged between them. 128. Tooth-picks may be useful in removing any particles maccessible to the brush. They may be made of bone, ivory or the common goosc-quill. Metallic tooth-picks should not bo used, as they injure the enamel. 129. The whole mouth should be washed with pure, tepid water, at night, as well as in the morning, after which the teeth should be brushed upward and downward, both on the posterior and anterior surfaces. It may be beneficial to use refined soap once or twice every week, to remove any corroding suiv stance that may exist around the teeth, care being taken to thoroughly rinse the mouth after its use. 12.5, Give another use of these organs. 126. Dc they contribute to the symmetry of the lower part of the face ? 127 — 132. Give the hygiem of the teeth, 127. By what means can the teeth be preserved ? 128. What is said of the use of tooth-picks ? 129. How often shouul the teeth be brushed ? V'' 46 ANATOMY, PHYSIOLOGY, AND HYGIENE. 130. Food or drink should not he taken into the mouth \ohen very hot or very cold. Sudden changes of temperature will crack the enamel, and, finally, produce decayed teeth. . Observation. On this account, smoking is pernicious, be- cause the teeth are subjected to an alternate inhalation of both cold and warm air. 131. Care should he taken^ in childhood^ that the temporary teeth be removed as soon as they become loose^ in order that the second set of teeth may present a regular and beautiful appear- ance. If a permanent tooth makes its appearance before the first is removed, or has become loose, the milk-tooth, although not loose, should be removed without delay. 132. If the teeth are crowded and irregular, in consequence of the jaw being narrow and short, or when they press so hard upon each other as to injure the enamel, remove one or more, to prevent their looking unsightly and irregular, and in a few months, the remaining teeth, with a little care, will fill the spaces. Observations. 1st. It is not always necessary to have teeth extracted when they ache. The nerve may be diseased, and the tooth still be sound. 2d. When it is ntcessary to have decayed teeth filled, it is better for the health of the person and durability of the teeth, to have them filled with gold foil. 130. What is the cause of decayed teeth ? Why is smoking injurioui to the teeth? 131. What remarks respecting the temporary teeth? 132. Give other remarks in regard to the temporary teeth. Give obser- vation Ist. Observation 2d. ANATOiifr or TUB DIGESTIVB OBOANB. 47 CHAPTER X. DIGESTIVE ORGANS. 133. The food, whether animal or vegetable, has no resem- blance to the bones, muscles, and other parts of the body to which it gives sustenance. It must undergo certain essential alterations before it can become a part of the diffcrcv* struc- tures of the body. The first change is effected by tft? actioa of the Digestive Organs. ANATOMY OF THE DIGESTIVE ORGANS. Fig. 32. Fig. J2 A view of the salivary glands in their proper situations. 1, The parotid gland 2, Its duct. 3, 7'he submaxillary gland. 4, Its duct. 5, The sublingual gland, Drought to view by the removal of a section of the lower Jaw. 138. Has aniraal or vegetable food any resemblance to the different parts ot the body to which it f^ives sustenance ^ By what organs is th» iu«t change in the food effected ? Describe fig. 32. ■f* n. 48 ANATOMY, PHTSIOLOQY, AND nYGIENl 134. Tho DIGESTIVE ORGANS are the Mouth, Teeth, SaVl va-i-y Glands, Phar'ynx, (E-soph'a-ijiis, (gullet,) Stomach, In-te^tines, ^bowels,) Lac'te-als, (milk or chyle vessels,) Tho-ra(/ic Duct, Lit/er, and the Pan'cre-aa, (sweetbread.) 135. The MOUTH is an irregular cavity, which contains the leeth and the organs of taste. 136. The SALIVARY GLANDS* are six in number; three on each side of the jaw. They are called the pOrrotUd, the suh-max'il-la-ry, and the suh-Un'gual. (Fig. 32.) 1 37. The PHARYNX is a mvuscular, membranous sac, that leadg 10 tile oesophagus. Fig. 33. I r'ig. 33. A side view of the face, oesophagus, nnd tracben. 1, Zf The trachea (wind-pipe) find larynx. 3, The ossophagiis. 4, 4, 4, The muscles of the upper pt)r- tion of the (esophagus, forming the pharynx. 5, The muscles of the cheek. 6, Tie muscle that surrouuds the mouth. 7, The muscle that forms the floor of the mouth * See paragraph 234. 134 — 147. Give the anatomy of the dir/estive organs. 134. Name the digestive organs. 135. Describe the mouth. 136. Describe the rsihvary glanda. 137. What is the pharynx ? What doea fig. 33 represent ? ANATOMY OF THE DIGESTIVE ORGANS. 49 138. The CESOPHAGUS is a largo, momhranous tube, through which the food and drink pass into the stomach. 139. The STOMACH * is in the left side of the body, below the lungs and heart. It is composed of three coats, or mem- branes, which are thin and yielding. The external is called the se'rons ; the middle mus'cu-Iar ; the inner, mn'cnns. Illustration. The three coulsof the stomach (anatomicallv^ resemble tripe, which is a preparation of the largest stomach of the cow or ox. The outer coat is smooth and highly polished. The middle coat is comjujsed of minute threads, which are arranged in two layers. The fibres of these layers cross each other. The inner coat is soft, and presents many folds, usually called " the honey-comb." Fig. 34. Fig. 34. The Inner emrface of the gtomach and duodenum. 1, The lower portion of the oesophagus. 2, The opening through which the food is passed into the stomach 3, The stomach. 9, The opening throtigh which the food passes out of the stomach into the duodenum, or upper portion of the Rmall intestine. 10, ;i, 14, The duode- num. 12, 13, Ducts through which bile and pancreatic fluid pass into it, a, 6, «, The three coats of the stomach. For situation of the stomach, &c., see fig. 63. 138 What is the oesophagus. 139. Where is the stomach situated? How many coats has it ? Name them. What Article prepared for food does the slmnach resemble iq Btructute ? KxpUiin fig. 34. 50 ANATOMY, PHYSIOLOGY, AND HYGIENE, 140. The INTESTINES, or alimentary canal, are diviJed into two parts, the small and large. The small intestine is aboui twenty-live feet in length. The upper and most important division is called the Du-o-deJnnm. The large intestme is about five feet in length. The largest division is callea the Co'lon. 141. The DUODENUM (called by nurses the second stomach) 18 the most essential part of the small intestine. It is about twelve inches in length, and commences at the lower orifico of the stomach. Fig- 35. Fig. 35. 1,1, The duodenum. 2,3, Tho small intestine. 3. The conaectlon jI Uie small and large inteBtine. 4, 5, 6. 7, 8, 9, 10, The large intestine. 6, 7, 8, 9, T6s colon. 140. How are the intestines divided ? What is the length of the small (kiteatine ? What is its lurgeat division culled ? What is the length of th« large intestine ? What is its luigest division cal/cd ? 141. Describe the duodenum. Explain fig. 35. / h /; /.,/ iV /, /v' ANATOMY OF THE DIGESTIVE ORGANS. 51 142. The LACTEALS are minute vessels, which open- upon tho mucous surface of the small intestine. From the mtestne they pass through small glands, {mes-en-ler'ic^) to the thuracio diict Fig. .3fi, Fig. 36. A portion of C*^ "tnall intestine, lacteal vessels, mesenteric glands ani thoracic duct. 1, The intestine. 2, 3, 4, Mesenteric glands, through which th» lacteals pass to the thoracic duct. 5, 6, The thoracic duct. 7, The point in the neck where it turns down to «*nter the vein at 8. 9, 10, The aorta. II, 13, Vessels of the neck. 13, 14, 15, The large veins that convey the blood and chyle to the heart. 17, 17, The spinal colunriO. 18, The diaphragm, (midriff.) 142. What are lacteals ? Through what do they pass as they proceed t« the thoracic duct ? Describe fig. 36. 68 ANATOMY, PHYSIOLOGY, ANb HYGIENE. 143. The THORACIC duct commences behind the liver, ajid ascends in front of the spinal column. At the lower part of the neck, il turns downward and forward, and pours its con- ten 5 into the vein behind the collar-bone. (8, fig. 36.) This due is equal in diameter to a goose-quill. 144. The LIVER is in the right side of the body, below the right lung. On tlie under side of this organ is a small sac, which contains a yellow, bitter fluid, called bile^ (gall.) Observation. The bile does not flow into the healthy stomach, Dut into the duodenum. With many persons, the imagination is biliouSy not the stomach. 145. The PANCREAS is a long, flattened organ, situated be- hind and below the stomach. From it there flows a fluid into the duodenum, called pan-cre-at'ic juice. Obsenmlion. A good idea of the liver, pancreas, and intes- tines can be obtained by examining these parts of a pig. In this animal, the sacs or pouches of the large intestine are well defined. 146. The i.T'LEEN, (milt,) so called because the ancients supposed it to be the seat of melancholy, is an oblong, flattened organ, situated in the left side, in contact with the stomach and pancreas. Its use is not well determined. 147. The OMENTUM (caul) is composed of adipose matter, (fat,) deposited between layers of serous membrane. It is attached tq the stomach, and lies on the anterior surface of the intestines. In some persons of gross habits, this deposit is very great. 143. Describe -ourse of the thoracio duct. What is its size) 144. Describe ♦ What is found upon its under surface ? Give ob- servation, jribe the pancreas. How may an idea of the liver be obtaJned describe the spleen. Is its use well known ? 147. De- scribe th<. .NiUtAUO. PHTSIv ^,v^Y OF TUB DIGESTIVE OBOAN8. 68 CHAPTER XI. PHYSIOLOGY OP THE DIGESTIVE ORGANS. 148. Substances received into the stomach as food, must necessarily undergo many changes before they are fitted to form part of the animal body. The solid portit)n8 arc reduced to a fluid state, and those parts that will nounsii the body are separated from the waste material. 149. The first change in the food is made in the mouth, by the teeth, and the sa-li'va (spittle) from the salivary glands. The teeth divide, while the saliva moistens and softens the food, si that, when carried into the pharynx, it is passed, with ease, thi ugh the GBsophagus into the stomach. 150. In swallowing, tlie food is pressed by the contraction of the muscles 5, 6, 7, (fig. 33,) into the pharynx, from which It is carried into the oesophagus, by the contraction of tho muscles 4, 4, 4. As soon as the food is received into this Xuhe its muscular coat contracts upon it successively \rom above downward, and the alimentary ball is pressed onward into the stomach. Observation. The process of* swi"ov/ing, or deglutition, is easily observed, when a person passes either liquid or solid food into the stomach. 151. The nex* change in llie food is in the stomach. The coats of the stomach contract, and the food is moved around, while, at the same time, a peculiar fluid is suoplied by the 148 — 159. Give the icse of the digestive organs. 148 "Wh«* ia necessary before food ran nourish ♦he body ? 149.' Describe the first chanj?e in the food. 150. Give the process by which the food is passed into the stomach H<*w may the process of swallowing be ooscrved ? 151. Where U tne lecond change in the food effected ? How is it done i 5* 54 ANATOMY, PHVSIOLOGY, AND HYGIENK. Stomach, caUed gastric juice, which mixes with the food, and reduces it to a soft, pulpy mass, called chyme. 152. This pulpy, grayish substance is passed into the duo- denum, and, by the action of the bile and pancreatic juice, it is changed into two parts — a milk-like substance, called c/iyZe ; and re-sid'u-um, or waste matter. 153. The chyle and residuum pass from the duodenum i»^.to the remaining portion of the small intestine, and are moved along by a worm-like action of its parts. 154. As these two substances are moved along the intestine, the chyle is sucked up by the lacteal vessels,* that pass through the small intestine, and the residuum is carried into the large intestine, and r cd from the system. 155. '^o recapitulate : In the adaptation of the food to the wonts of the body, it is subjected to five different changes. 1st. It is changed in the mouth, by the action of the teeth and saliva. This is called mastication. 156. 2d. By the action of the stomach and gastric juice, it is changed into a pulpy, homogeneous mass. This is called chymijication. 157. 3d. In the duodenum, the bile and pannreatic juice change the chyme into chyle. This is called ckiflification. 158. 4th. By the action of the lacteal vessels and thoracic duct, the chyle is poured into a vein behind the collar-bone, and passes through the heart to the lungs ; here, by the action of the air, it becomes blood. '(See Chap. XX.) 159. 5th. The separation and excretion of the residuum. ♦ The chyle is changed by the lactcals and mesenteric glands, but the nature of this change is not, as yet, well defined or understood. 152. What becomes of this pulpy substance? What change is effected In the duodenum ? i.53. "Where do the chyle and residuum then pass ? 1/J4. What becomes of the chyle { Of the residuur^ ? 155. Recapitulate the five changes in the digestive process. Note. Let the pupil review the anatomy and physiology of the digestive rgans, t'rom figs. 30 and 37, or from outline anatomical plate 6. tHYSlOLOGY OF THE DIGESTIVE ORGANS. bk Fig. 37. Irig. 37. An ideal view of the organs of digeation, opened neatly the whole lenptlk 1, The uppei jaw. 2, TKj lower jaw. 3, The tongue. 4, The roof of the mouth. 5, The CBSophagus. 6, Thetraclica. 7, The parotid ghind. 8, The siiblingual gland. », The stomach. 10, 10, Tlie liver. 11, The gall-cst, or sac. 12, The duct ti.at conveys the bile to the luodtnum, (13, 13.) 14, The pancreas. 15, 15, 1.5, 15, Th« ■mall intestine. 16, Tlie opening of the small intestine into the large intestitie 17, 18, 19, SO, The large intestine. 21, The spleen. '22, The upper part of tlie spine column 6tt ANATOMY, PHYSIOLOGY, AND HYGIENK. CHAPTER XII. HYGIENE OF THE DIGESTIVE ORGANS. 160. The perfection of the digestive process, as well as tho health of the body, requires the observance of certain condi- tions. These will be considered under four heads. 1st. The quantity of food that should be taken. 2d. Il8 quality. 3d. The maimer in which it should be taken. 4th. The con- dilion of the system when food is taken. 161. The QUANTITY of food necessary for the system varies. Although many things may aid us in determining the quantity of food proper for an individual, yet there is no certain guide in all cases. Age, occupation, habits, temperament, tempera- ture, nealth, and disease, all exert an influence. 162. The. child and youth require food to promote the groicth of the bones, muscles, and the different parts of the body. The more ra})id the growth of the child, the greater the demand for food. This accounts for the keen appetite and vigorous digestion in childhood. 163. Food is necessary to repair the waste which attends the functions of the different organs. The waste is greatest when we exercise most. For this reason, when we increase our exercise or labor, the quantity of food may be increased ; while, on the other hand, when we change from an active em- 160 — 186. Give the hyyiene of the digestive organs. 160. What does the perfection of the digestive process require ? 161. Can the quantity of food proper for an individual be determined in all cases ? What exert an Influence on the quantity necessary for the body ? 162. At what age is the appetite keen and the digestion vigorous ? Why ? 163. Give another db- mand for food. When is the waste greatest ? When should the amount of food be lessened ? HYGIENE OF THE DIGESTIVE ORGAXS. 67 ployment to one less active in character, the food should be diminished in nearly the same degree that the exercise is lessened. 164. When the girl leaves the active household employ- ments for the shop of the dress-maker, — when the boy leaves the farm for the school-room, — the amount of food should be diminished as soon as the sedentary employment is com- menced ; for, under such circumstances, the appetite will n(»t guide correctly. Ohservation. It is a common observation, that in academies and colleges, the older students from the country, who have been accustomed to hard manual labor, sufTcr more frequently from defective digestion and impaired health than the youngci and feebler students from the larger towns or cities. 165. The food aids in supporting the icarmth of the body. This is the reason why the apjsetite for food is keener in the winter than in the summer. It follows, then, that the system requires more food in cold than in hot weather. Observations. 1st. Well-clothed children require less food in cold weather than those thinly dressed. 2d. Flocks and herds that are sheltered in winter, will eat ont, third less than if exposed to the inclemency of the weather; hence it is true economy to keep the infeiior animals warm, as well as children. 166. In all instances^ the quantity of food should have reference to the present condition of the digestive organs. If they are weakened or diseased, so that but a small quantity of food can be properly digested or changed, that amount only should be taken. Food does not invigonite the system, except it is changed, as has been described in Chap. XI. 167. The QUALITY of the food best adapted to the wants of 164. When will not the appetite guide correctly ? What observation re- specting tliosc students that have been accustomed to hard manual laboi / 16.5. AVhy is the appetite for food keener in the winter than in the sumnici * Give observation 1st. Observation 2d. 166. Why should the present condition of the digestive organs be regarded in reference to the quantity ot food? 167. On what does the quality of food adapted to the wmts of the system depend '. 58 aNATOMy, PHYSIOLOGY, AND HYGIENE. the syf»tein depends upon the season, climate, age, «S«j., of a person. Like the quantity necessary for an individual, there can be no fixed law. 168. The kind of food lohich is eaten should be adapted to the distensible character of the stomach and alimentary canal. Hence the food should contain nutritious and innutritious mat- ter — nutritious, to promote the growth and repair the waste of the system ; and innutritious, to distend both the stomach and alimentary canal. Consequently, hot flour bread, rich pies, and jellies, are not so good articles for food, as the unbolted wheat bread, ripe fruits, and berries. 169. The infuence of season and climate shcvld be consid- ered in selecting food. Food of a highly stimulating character may he used almost with impunity, during the cold weather of a cold climate, but in the warm season, and in a warm climate, it would be very injurious. Animal food, being more stimu- lating than vegetable, can be eaten in the winter; but vegetable food should be used more freely in the spring and summer. Observation. By abstaining from meats and stimulating drinks in warm weather, and living on nutritious, unstimulating food, the "season" or bowel complaints may be, in a great degree, prevented. 170. The age of persons modifes the injlucnce of food on the system. The organs of a child are more sensitive and excita' ble than those of a person advanced in years. Therefore a vegetable_diet would be most appropriate for a child, while stimulating animal food might be conducive to the health of an aged person. 171. The MANNER in which food should be taken is of much practical importance ; upon it the health of the digestive organs depends. 168. What should all substances used for food contain? Why? 169. Should the season of the year influence us in selecting food ? Give observation. 170. What kind of food is adapted to the organs of the child ? Why ? What kind to a person advanced in life ? Why ? 171 What ia rfurt of ths manner of taking food ? HYGIENE OF THE DIGESTIVE ORGANS. 69 172. Food should he taken at regular periods. The interval between meals should be regulated by the kind of food, the age, health, exercise, and habits of the individual. Children re- quire food more frequently than adults ; yet, strict regularity and i/unctuality should be observed in regard to their cimes of eaung. 173. Food should not be taken too frequently. If food is taken before the stomach has regained its tone and energy by repose, or before the digestion of the preceding meal has been completed, not only will the action of the stomach be imperfect, but the food partially digested becomes mixed with that last taken, inducing irritation or disease. In general, an adult should allow six hours to intervene between meals. 174. Food should be well masticated^ or chewed. All solid food should be reduced to a state of comparative fineness, by the teeth, before it is swallowed ; the gastric fluid of the stomach will then blend with it more readily, and act more vigorously m reducing it to chyme. 175. Mastication should be moderate^ not rapid ; for the salivary gland% are excited to action in chewing, and some time must elapse before they can secrete saliva in sufficient quantities to moisten the food. 176. Food should be masticated and swallowed without drink. As the salivary glands supply fluid to moisten the dry food, the use of tea, coflee, water, or any other fluid, is not demanded by nature's laws while taking a meal. Observation. Were it customary not to place drinks on the tiible until the solid food is eaten, the evil arising from drinking too much at meals would be obviated. 177. The CONDITION of the system should be regarded when food is taken. 172. How should food be taken ? How shoiild the intervals between meals be regulated ? What should be observed in giving food to children ? 173. What is the effect if food is taken too freciuently ? 174. Why should food be well masticated i" 17o. Why should we i:ot oat rapidly ? 176. Why do we not require drink while chewing our f )od ? 177. Should the con- dition of the system be regarded when food is taken ? 60 ANATOMY, PHYSIOLOGr, AND HYGIENE 178. Food should not be taken immediately after severe exer- tioiiy either of the body or mind ; for all ori^aiis in action require and receive more blood and nervous fluid, than when at rest. Observation. Tije practice of students and accountants going inuneiliately from severe mental labor to their meals, is a pernicious one, and a fruitful cause of indigestion and mental debility. The custom of farmers and mechanics hurrying from their toil to the dinner-table, "to save time," — which, to say the least, is poor economy, — does much to cause dyspepsia among these classes in community. 179. Severe mental or physical labor should not be entered upon immediately after eating. The amount of blood and nervous fluid supplied to the stomach and alimentary cana! during the digestion of food is increased, and a deficiency con- sequently exists in other organs. If the blood is diverted from the stomach to the limbs or brain by active exertion, it will not only cause disease of the digestive organs, but chyle will not be formed, to nourish the system. ISO. Pure air is necessary to give a keen appetite and vigor- ous digestion. The digestive organs not only need the stimulus of blood, but they absolutely need the influence of pure blood, which cannot exist in the system, except when we breathe pure air. Illustration. A manufacturer stated before a committee of Ihe British parliament, that he removed an arrangement for ventilating his mill, because he noticed that his men ate much more after his mill was ventilated than previous to admitting fresh air into the rooms. The apology for removing the venti- lators was, that he could not afford to have them breathe pure air. 178. Why should not food be taken after severe exertion ? AVhat is one cause of indigestion among students and accountants ? What is said of farmers and mechanics hurrying from their toil to the dinner-table ? 179. Why should not severe exertion be made immediately after eatint{ ? 180. Wtat effect has pure air on digestion ? Give illustration. HYGIENE OF THE DIGESTIVE ORGANS. 61 181. Persons should abstain from eatings at least three hours before retiring for sleep. It is no unusual occurrenco for those persons wlio liave eaten heartily irnmcchately before retiring for sleep, to have unpleasant dreams, or to be aroused from their unquiet slumber by colic pains. Illustration. A healthy farmer, who was in the habit of eating one fourth of a mince pie immediately before going to bed, became annoyed with unpleasant dreams, and, among the varied images of his fancy, he saw that of his deceased father Becoming alarmed, he consulted a physician, who, after a patient hearing of the case, gravely advised him to eat halfoCa mince pie, assuring him that he would then see his grandfather. 182. When the eeneral system and digestive organs are mfeebledt mild^ unstimulating food^ in small quantities, should be given. In the instance of a shipwrecked and famished mariner, or a patient recovering from disease, but a small quantity of nourishment should be given at a time. 183. Water and most fluids are removed from the stomach in a very few mmutes, by the action of the veins. In instances of great feebleness, the body can be strengthened sooner by liquid than by solid food. 184. When travelling in coaches or cars, the stomach is not m a- state to digest large quantities of food. When food is taken, it should be of the mildest character, and small in quantity. 185. To prevent disease, it is as necessary that the alimen- tary canal be evacuated regularly, as that we take fcod hito the stomach at regular periods. 186. Sitting, standing, and walking erect, aid in keeping the digestive organs healthy. 181. What is the cflcct of eating immediately before retiring for sleep ? Haw is this illustrated in the case of a healthy farmer ? 182. IIow should food be given when both the digestive organs and general system are en- feebled ? 183. A\1iich are introduced into the system soonest, fluids or solid food ? 184. What is said in regard to food while we are travelling ? ).86 Wh»t positioB of the body aids digestion ? 6 W ANATOMY, PHYSIOLOGY, AND HYGIENE. CHAPTER XIII. THE CIRCULATORY ORGANS. 187. The blood is distributed lo every part of the systeni. riicre is no part so minute, that it does not receive this circu- lating fluid. This distribution is effected by the agency of the Heart, Ar'te-ries, Veins, and Cap'il-la-ries. ANATOMY OF THE CIRCULATORY ORGANS. 188. The HEART is situated in the chest, between the lungs. (Fig. 53.) It is a double organ, or has two sides, called right and left, which are separated by a muscular sep'tum, or partition. 189. Each side of the heart has two cavities. The upper cavity is called the au'ri-cle, (deaf ear.) The lower cavity is called the ven'tri-cle. These cavities are separated from each other by folds of membrane, called valves. (Fig. 38.) 190. Between the auricle and ventricle of the right side of the heart, there are three valves, called tri-ciis'pid. Between the auricle and ventricle of the left side of the heart, there are two valves, called mi'tral. Observation. To obtain a clear idea of the heart and its valves, it is recommended to examine this part of an ox or calf. In order that each ventricle be opened without muti- 187. "What is said of the distribution of the blood ? How is it effected ? 188—196. Give the anatomy of the circulatcry organs. 188. Describe the heart. 189. How many cavities has it ? What is the upper cavity called ? What is the lower cavity called ? How are these cavities separated ? 190. How many valves between the right auricle and ventricle, and what are they called ? How many valves between the left auricle and ventricle, and «hat are they called t How can an idea of the heart be obtained i ANATOMY OF THE CIRCULATORY ORGANS. 63 latlng the parts that compose its internal structure, out on each side of the septum parallel to it. This may be easily found between the ventricles, as they diirer in thickness. 191. The ARTERIES are the vessels that carry the blood fronj the heart. The right ventricle of the heart gives rise to the ful'mo-na-ry artery ; the left ventricle to a large artery, called the a-ort'a. At the lommencemont of both of these vessels are valves, and from their shape, they are called sevi-i-lu'nar Fig. 38. Fig 38. I, The descending vein. 2, The ascending vein. 3, Tho right niiricle 4 The opening between the ritiht auricle and the riglit ventricle. 5, The right ven tixle. 6, The tricuspid val"es. 7, The pulmonary artery. 8, 8, The branches o? the ptilinonary artery that pass to the right and left lung. 9, The semihinar valves of ti.e pulmonary artery. 10, The division between the two ventricles of the heart, li, 11, The pulmonary veins. 12, The left auricle. 13, The opening between tJio lei auricle and ventricle. 14, The left ventricle. 15, The mitral valves. 16, IC, The aorta. 17, The semilunar valves of the aorta. Observotion. The parts of the circulatory organs most liable to disease are the valves of the heart, particularly the mitral. T91. What are arteries ? Where does the puhnonary artery take ita ri«^ ? The aort? ? What valves ut the commencement of these vessels ? IVscribe fig. 38. What parts of the circulatory organs are most liable tc dtv«a8e? T ■^ *^ ^' 4' ■f '■ / 64 ANATOMY, irHYSIOLOGY, AND HYGIENE. V^'Tien tMese mcmbmnous folds become ossified or rupti'.rea ihe blood regurgitates, and causes great distress in breathing. 192. The PULMONARY ARTERY conimcnccs in front of the aorta. It ascends obliquely to the under surface of ihe arch of (he aorta, where it divicJcs into two branches, one of which passes to the right, the other to tiic left lung. This artery conveys the dark-colored or "venous" blood to the lungs, and, with its corresponding veins, establishes the pulmonic circU' lalion. Fig. 39. Fig. 39. t, The windpipe, h, The heart, d, The aorta, p. The pulmonary aiiery. 1, Tne biancli of the pulmonary artery that divides in the left lung. 2, The Dranch that divides in tlie right luni?. Tlie divisions of this artery continue to divide and subdivide, until they become no larger than hairs in si/.c. Tlie^^e minute vessels pass over the air-cells, represented by ■mall dark points around the margin of tlie lungs. 192. Describe the pulmonary artery. "WTiat is the function of this artery ? Explain fig. 39. What is said of the divisions of the pulmon»r.» trtery? ANATOMY OF THE CIRCULATORY ORGANS. QS» 193. The AORTA proceeds from the left ventricle of the heart and contains the pure or "arterial" blood. This vessoi gives off branches, which divide and subdivide as they advance until they are distributed to every part of the body. Thia artery, with its corresponding veins, establishes the systemic circulation Fig. 40 Fig 40. The aorta and its branches, a, The commencement of the sottk. 193. Describe the aorta. What is represented by fig. 40 ? 6* 66 ANATOMY, PHYSIOLOGY, AND HYGIENE. 1J4. Tha VEINS are the vessels which return the blood to the auricles of the heart, after it has been circulated by the arteries through the lungs and other parts of ihe body. A certain inter>'als, they are furnished with valves, which allow the blood to flow toward the heart only. In general, they arc nearer the surface of the body than the arteries. 195. The CAPILLARIES constitute a microscopic net-work, and are so distributed through every part of the body as to ren- der it impossible to introduce the smallest needle beneath the skin .vithout wounding several of these fine vessels. They establish the communication between the termination of the arteries and the beginning of the veins. 196. The relation of the capillaries to the arteries and veins, is illustrated by figs. 41 and 42. Fig. 41. Fig. 41. An ideal view of a p<.rtion of the pulmonic circulation. 1, 1, A branch •f the drtery that carries the impure blood to the lungs 3, 3, Capillary vessels t, 2, A vein through which the red blood is returned to the left side of the heart Fig. 42. An Ideal view of a portion of the systemic circulation 1, i, A branch •f the aorta. This terminates in the capillaries 3, 3. 2, 2, A vein through which the Impure blond is carried to the right side of the heart. 194 What are veins ? With what are they furnished ? 195. What do the Cftpillaries constitute ? What do they establish ? What does fig. 41 represent? Fig. 42? PRI&IOLOOY or THE CIRCULATORY OROANS. 67 CHAPTER XIV. PHYSIOLOGY OF THE CIRCULATORY GROANS. 197. The walls of all the cavities of the heart are composed of muscular fibres, which are endowed with the property of con- tracting and relaxing, like other parts of the muscular system The contraction and relaxation of the muscular fibres of the heart increase and diminish the size of its ca/ities. 198. The two auricles dilate at the same instant, and also contract at the same instant. The two ventricles cdhtract, while the auricles dilate. Thus the blood is forced from the heart to every part of the body, and received again on its return. 199. The roTirse of the blood through the heart, arteries, and veins, may be easily comprehended by attention to fig. 43, which gives an ideal view of the circulation of the blood. 209. The heart aids iu forcing the blood through the arte- ries, to the different parts of the body. Every time the heart contracts, there is a " pulse," or " pulsation," in the arteries. Experiment. Apply the fingers upon the artery at the wrist, at two different points, about two inches apart ; if the pressure be moderately made, the "pulse" will be felt at both points. Let the upper point be pressed firmly, and there will be no pulsation at the lower point; but make strong pressure upon the lower point only, and the pulsation will continue at the upper point; proving that the blood flows from the heart, in the arteries, to different parts of the system, 197—203. Give the physiology of the circulatory organs. 197 What do the contraction and relaxation of the muscular walls of the heart produce ? 19^ What is said of the contraction and dilatation of the auricles ? Of the ventricles ? 200. What causes the " pulse," or •' pulsation," in the arterien ? How is it proved that the blood flows from the heart in thb sxteries ? 68 ANATOiMY, PHYSlOLOUy, AND IIYaiENB. 201. The frequency of the pulse varies according to tht age, sex, and degree of health. In adults, it is usually from seventy to seventy-five "beats" in a minute. 202. There is no pulsation in the veins, and the return of the blood to the heart through them can be shown by the fol- lowing experiments. Experiments 1st. Press firmly on one of the veins upon the back of the hand, carrying the pressure toward the fingers ; for a moment the vein will disappear. On removing the pressure of the finger, it will reappear, from the blood rushing in from below. 2d. If a tape be tied around the arm above the elbow, the veins below will become larger and more prominent, and also a greater nunflber will be brought in view. At this time, apj.Iy the finger at the wrist, and the pulsation of the arteries still continues, showing that ihe blood is constantly flowing from the heart, through the arteries, into the veins ; and the increased size of the veins shows that the pressure of the tape prevents its flowing back to the heart. 203. From the right ventricle of the heart, (2, fig. 43?) the dark, impure blood is forced into the pulmonary artery, (3 ;) and its branches (4, 5) carry the blood to the left and right lung. In the capillary vessels (6, 6) of the lungs fixe blood becomes pure, or of a red color, and is returned to t' left auri- cle of the heart, (9,) by the veins, (7, 8.) From the left auri- cle the pure blood passes into the left ventricle, (10.) By a forcible contraction of the left ventricle of the heait, the blood is thrown into the aorta, (11.) Its branches (12, IS, 13) carry the pure blood to every organ, or part of the body. The divisions and sjbdivisions of the aorta terminate in capillary vessels, represented by 14, 14. In these hair-like vessels the blood becomes dark-colored, and is returned to the right auricle of the heart, (1,) by the ve'na ca'va de-scen' dens (15) and ve'na cava as-cen'dens^ ( 16.) The tricuspid valves ( 17) pre- vent the reflow of the blood from the right ventricle to the righi 201. What varies the frequency of the pulse ? 202. Is there pulsation in the veins ? How is it proved, by experiment 1st, that the blood is returned to the heart by the veins ? By experiment 2d ? PHYSIOLOGY OF THE CIRCULATORY ORGANS. 69 auricle. The semilunar valves ( 18) prevent the blood passing from the pulmonary artery to the right ventricle. The mitral valves (19) prevent the flow of blood from the left ventricle to the left auricle. The semilunar valves (20) prevent thr ^eflow of blt)od from the aona to the left ventricle. Fig. 43. Noti^ From fig. 43. give the course of the blood thiuugh th» heart, arte •^s, and veins, or from anatomical outline plates 6 and 7. 70 ANATOMY, FHYSIOLOGY, AND HYGIEME. CHAPTER XV. HYGIENE OF THE CIRCULATORY ORGANS. 204. The clothing should he loosely worn. To have good nealth^ the blood must circulate freely. Consequently, no arti- cle of apparel should be worn so as to prevent a free flow of blood through every organ of the body. 205. Strings, bands, or belts, however narrow, should not be worn so tightly as to cause an indentation of the skin of the trunk, or extremities. Observations. 1st. Inelastic bands, worn upon the lower extremities, are a frequent cause of enlarged veins and painful limbs. 2d. The fulness and the crimson tint of the face, gid- diness, fainting, and many derangements in the functions of differei-t organs, are produced by pressure upon the blood- ves.=els of the trunk. 206. The skin should be kept clean, and every part of an equal teinperature. These conditions favor free and vigorous circulation. Observation. When intending to ride in a cold day, wash Uie face, hands, and feet, in cold water, and rub them smartly with a coarse towel. This is far better than to take spirits into the stomach, to keep the extremities warm. 207. Muscular exercise is important in maintaining a 204 — 214. Give the hygiene of the circulatory organs. 204. Why should the clothing be loosely worn ? 205. What is said of bands or belts ? What is the effect of wearing inelastic bands upon the lower extremities ? What is a frequent cause of giddiness, faintness, and derangement of the func- tions of many organs ? 206. In what condition should the skin be kept? Give observation. 207. What is the effect of muscular exercise apon the circulatiou uf bluod ? HYGIENE OF TH.S CIRCULATORY ORGANS 71 nealthj circulation. The muscles, when used, force the blood more rapidly to and from the heart. Illustration. The coach-driver and teamster throw their arms around their bodies to warm them, when cold ; because the muscles that are called into action in swingii. g the arms, force a greater quantity of blood into the chilled parts, and n\ore heat is produced. 208. Idle men and women, who complain of cold feet, and take " warming bitters " to quicken the blood, would find them- selves warmer and more invigorated by culling the muscles into action in the mechanic's shop, or the kitchen, or in some active employment. Observation. In cold weather, when travelling in cars, the feet will not become chilled so readily when standing as when sitting. Again, the feet will be warmer by allowing them to swing, instead of being supported the whole time, because tiie muscles, called into action in swinging them, increase the cir- culation of the blood. 209. The quality and quantity of the blood modify the action of the heart and blood-vessels. If this fluid is abundant and pure, the circulatory vessels act with more energy than when it is deficient in quantity or defective in quality. Illustrations. 1st. In an athletic man, whose heart beats forcibly, and whose pulse is strong, if a considerable quantity of blood is drawn from a vein, as in bleeding, the heart will beat feebly, and the pulse will become weak. 2d. When the blood is made impure by inhaling vitiated air, the action of the heart and arteries is diminished, which pro- duces an effect similar to that which takes piace when blood ia drawn from a vein. 210. When large blood-vessels are wounded or cut, the Give illustration. 208. What is better for cold feet and hands than ♦ warming bitters " ? Give observation 209. What effect have the quantity and quality of the blood upon the circulatory vessels ? Give illustration 1st. Illustration 2d. 210. What is necessary when large blood-vesseU aie wounded or cut ? 72 ANATOMY, PHYSIOLOGY, AND HYGIENE. flow of blood must be immediately stopped, or the person will soon die. If a large artery is wounded, the blood will be thrown out in jets, or jerks, every time the pulse beats. The flow of blood can be stopped until a surgeon arrives, *>4ther by comp/esining the vessel between the wound and the heart, or by compressing the end of the divided artery in the wound. Fig. 46. Fig. 44. The track of the large artery of the ann 1, The collar-bone. 9, 10, The •arge artery of the arm. Fig. 45. B, Tlie manner of compressing tlie artery near the collar-bone. A, The manner of compressing the large artery of the arm, with the fingers. C, Th3 manner of compressing the divided extremity of an artery in the wound, with a finger. 21 1. After making compression with the fingers, as described and illustrated, take a piece of cloth or handkerchief, twist it cornerwise, and tie a hard knot midway between the two ends. "What is shown by fig. 44 ? By fig. 45 ? 211. What is to be done after comp'^essing the wound, as before described ? HYGIENE OF THE CIRCULATORY ORGANS. 78 riiis knot should be placed over the artery, between the wound and the heart, and the ends carried around the Hmb and loosely tied. A stick, five or six inches long, should bo placed under the handkerchief, which should be twisted until the knot has made sufficient compression on the artery to allow the removal of the fingers without a return of bleeding. Continue the compression until a surgeon can be culled. Fig. 4G Fi-'. 47. Fig. 4C. Tlie nietliod of applying tlie knotted Imndkerchiff to make cotnpreastou oa ihia filter)'. A, IJ, Tliu track of the larpe artery of the arm. TiS. 47. A, C, The track of the lar^ic artery of tlie thigh. 15, The method of ap ()lyiii^ the kiuittcd handkerchief to conipre.ss thiM artery. Observation. When an artery of the arm is cut, elevalitig the wounded limb above the head will tend to an t the ilcv of blood. In a wound of a lower limb, raise the fooi, so 'lat it shall be higher than the hip, until the bleeding ceases. Illustration. On one occasion, the distiti.ss by which sul> stanccs are separated from the blood, called secretion^ but th** same term is also applied to substances thus separated. Fig. 53. a a, A iecretory gland, b, b, Minute ducU tLki art apitad thrrmgh the ^iniidB. These coalesce to form th« main duct, c 236. All the fluids of the body arj derived from the blood, and this element, when distributed to the different glands and follicles, is similar in composition and character: but the fluids secreted by them, vary in appearance in a remarkable degree. The office of the glands is principally to form different secro- 234. Whiit is said of the glands ? Explain fig. 52. 2;i'>— 287. Crive '.he physiology of the ^cretory orgmis. 23.5. What is secretion ? 236. From what are all the fluid.s of the body dei-ved? What is the principal office af the glands ? 84 ANATOMY, PHYSIOLOGY, AND IIVr.IENE. tions. Thus the salivary glatids secrete the insipid sahva; the liver, tlie yellow, ropy bile ; and the kidneys, the acrid urine. 2.'J7. When any substance wliich is not demanded for nutri- tion, or does not give nouriq»ment to the sy tern, is taken up by the lymphatic vesbuls vu<-\ conveyed intD the blood, it is dis- charged by secretions. Tl/ustrafion. A few years since, a poor inebriate was carried to a London hospital in a state of intoxication. lie lived but a few hours. On examining his brain, nearly half a gill of fluid, strongly impregnated with gin, was found in the cavities of this organ. This was secreted from the vessels of the brain. HYGIENE OF THE SECRETORY ORGANS. 238. Unless the secretions are regularly maintained^ dis- ease will he the ultimate result. Let the secretions from the skin be suppressed, and fever or some internal inflammation will follow. If tliebiie is impeded, digestion will be impaired. If any other secretion is suppressed, it will cause a derange- ment of the various internal organs. Ohservation. Ardent spirits derange tiie secretions, and change the structure of the brain. This is one reason why inebriates do not live to advanced age. 239. The quantity of blood injluences the character of the secretions. If it is lessened to any great extent, the "-icretiona will be lessened, as well as changed in character. Illustration. When a person has lost a consider .c quantity of blood, tliere is a sensation of thirst in the throat, attended with a cold, pale, dry skin. WHien iTjaction comes on, the 237. What becomes of those substances which are taken up by the lymphatics, and do not nourish the body ? How is this illustrated ? 238 — 241. Give the /ii/r/ic/w of the secretory organs. 238. What is the effect on the system if the secretions are not regularly maintained ? What ia a reason that inebriates do not live to an advanced age ? 239. "What effect n the secfctions when the quantitj of hlood ia lessened ? How is this illustrated ? HYUIENE 01 THE SECllGru.l'V uKvJA^S 86 perspiration is cold, attended with nausea, and sometimes vomiting. 240. 77ie amount of action modifies the condition of the secretory organs. When a secretory offran is excessively stimulated, its vigor and energy are reduced. The subsequent debility may be so great as to suppress or destroy its functional power. Illustrations. 1st. In those sections of the country where flax is spun on a " foot-wheel," the spinners sometimes moisten tho thread with saliva. This seems to operate economically for a lime, but debility of the salivaiy organs soon follows, and they are incapfible of supplying saliva sufficient to moisten the food, producing, in a short time, disease of the digestive organs 2d. The habit of continual spitting, which attends the chew- ing of tobacoo and gums, induces debility, not only of the salivary glands, but of the system generally. 241. The secretions are much influenced by mental emo- tions. If we smell savory food, there wili be an increased flow of saliva ; if we hear the intelligence of the death of a cherished friend, the tear will quickly coai.se down the cheek. • Observation. Such is the nice sympathy which exists be- tween diflerent parts of the body, that in the evenings of the warm season, a chill upon the impressible skin that suppresses* the perspiration, is frequently followed by a diarrhoea, dysen- tery, or cholera morbus. These can be prevented by avoiding the chill. An efficient means of relief, is, immediately to restore the skin to its proper action. 5 240. What is the effect if a secretory organ is excessively stimulated ? How is this effect illustrated by the use of the saUvary glands ? 241. Door the state of the mind influence the secretions ? What is said of tho sym- pathy between different parts of the body ? 8 R6 ANATOTiY, PHYSIOLOGY, AND HYGIENE. CHAPTER XVIII. NUTRITION. 212. The blood is the nutritive fluid of animals. It i's com. posed of two parts — a watery fluid, called se'rum^ and a solift portion, called co-ag'u-Ium, (clot.) Observation. That portion of the serum which remains fluid after coagulation by heat has taken place, is called se-ros'i-tt/. It is more abundant in the blood of old, than in that of young animals ; and it forms the " red gravy " in roasted meats. 243. The blood is not necessarily red. It may be white, as m the fish ; .transparent, as in the insect ; or yellowish, as in the reptile. There is no animal in which the blood is red in all parts of the body. The ligaments and tendons, in man, are not supplied with red, but with white blood. 244. Nutrition is the vital act by which the different parts of the body renew the materials of which they are composed. Digestion, circulation, absorption, and respiration, are but sepa- rate links in the chain of nutrition, which would be destroyed by the absence of any one of them. 245. The nutritive process is a kind of secretion, by which particles of matter are separated from the blood, and conveyed with wonderful accuracy to the appropriate textures, or parts of the body. 246. The function of the nutrient vessels antagonize those of absorption ; while one system is constructing, with beautifu! 242. What is the nutritive fluid of animals? Of what is it composed? Wliat forms the red gravy in roasted meat ? 213. Wliat is said of the color of the blood? 244 — 248. W/iat remarks respecting nutrition* 244. What ia nutrition ? 24.5. Wliat is said of the nutrit-ve process ? 246. What can you say of the function of the nutrient vessel*. ? NuiniTioN. 87 precision, tlie animal frame, the other is diligently employed in pulling down this complicated structure. But amid this simultaneous renovation and decay, the form and beauty of the organs are preserved. Ohsenmtion This ever-changing state of the body is shown by giving animals colored matter, mixed with their food, which in a short time tinges their bones with the same color as the matter intrcHuced. Let it be withdrawn, and in a few days the bones will assume their former color — evidently from the eflects of absorption. The changeful state of the body is fur Iher shown, by the losses to which it is subjected ; by the necessity of aliment; by the emaciation which follows absti- nence from food. 247. The renewal of every part of the body is not perfected merely by the passage of the blood through the arteries of the systemic circulation, but by the smallest capillary vessels, called the nutrient arteries. 248. " As the blood goes the round of the circulation, the nutrient capillary vessels select and secrete those parts which are similar to the nature of the structure, and the other portions pass on; so that every part takes up and converts to its own use the very principles which it requires for its growth ; or, in other words, as the vital current Uj.pioaches each organ, the particles appropriate to it feel its attractive force, — obey it, — quit the stream, — mingle with the substance of its texture, — and are changed into its own true and proper natuie." Illustration. When a bone is broken, or a ner>e wounded, minute vessels shoot out from the living parts, and immediately commence their operations, by depositing bony matter, where it IS required to unite fractured bones, and nervous substance to heul the wounded nerve. Give a proof of thr over-chansiiif; stntc of the bod) . Give other in stances illui;trative of the chaiigcfiil state oi tlio body. 247. By what ves- sels is the reiie\^l of every part of the body perfeitcd ? 248. What is said of the office of the rmtrieiit capillary vessels .' When a bone is fractured, »i what pro'jess is it hcalcd ? 88 ANATOMY, PHYSIOLOGY, AND HYGIENK. Fig. 53. I Fig. .^. A front view »e dark color of the blood owing? Where is tais gas formed? 264. What element beside •■rbon la found in the bluod ? What dues it form w^en united with oxygen ? 90 ANATOMY, PHYSIOLOGY, /ND HYGIENE. 2d. Breathe upon a cold, dry mirror, for a few minutes, and it will be covered with moisture. This is condensed vapor from the lungs. In warm weather, this watery vapor is invisible ill the expired air ; but, in a cold, dry morning in winter, the suc- cessive jets of vapor issuing from the mouth and nose are BufTiciently obvious. 265. Atmospheric air, or tha which fills the air-cells of the lungs, is composed of two gases, ox'y-gen and ni'tro-gen. Oxy- gen has the property o! supposing life, while nitrogen alone would destroy it. But combined with the former gas, it serves to neutralize the otherwise irritating action of the oxygen. Pig. 58. 1, .- bronchial tube divided into three branches. 2, 2, 2, Air cells. 3, Branches of the puhnona/y artery, that spread over the a.r-cells. Through the pulmonary artery, the dark, impure blood is carried to the xir-cells of the lungs. 4, Rranciies of the pulmonary vein, that commence at the minutt^ terminations of the pulmonary artery. Through the pulmonary vein, the red blood is returned to the heart. 266. We will now pass to the change which the air effects when it comes in contact with the blood in the lungs. As the impure blood is passing in the minute vessels over the air-cells, the oxygen passes through th^ extreme thin coats of the air- cells and blood-vessels, and unites with the blood. At the same time, the carbonic acid and watery vapor leave the blood, and pass through the coats of the blood-vessels and air-cells, and irix with the air in the cells. These are expelled from the air- ^ow are these elements supplied to the blood ? How may the presonco o. Trbonic acid in the expired air be proved ? The presence of watery vapor ? 265. Of what is the air composed "* "What property has oxygen ? Has nitrogen ? 266. Explaiu how the blood is changed by the action of oe air. ■-«s^: PHVSIOLOGY OF THE RESPIRATORY ORGANS. 97 cells every time we breathe. This interchange of gases pro- duces the change in the color of the blood. Eicperimenl. To show that gases may be interchanged through membranes, fill a bladder with dark blood drawn from any ^nimal. Tie the bladder closely, and suspend it in the air. In a few hours, the blood next the membrane will have become of a bright red color. This is owing to the oxygen from the air passing through the bladder, and unit>»>g with the blood, while the carbonic acid has escaped through ihr mi^^t*. branc. Fig. 69. Pif .59. An ideal view of the pulmonary cirriilntion. 1, 1, The lipht luuR. 2, a, The left lung. 3, The tiiichea. 4, The hplit hronrhiai tube. 5, Tttti U'tt bronchial tube. 6. C, 6, G, Air-rells. 7, The right auricle. 8, The riglit ventricle. 9, Tne iricuspia vaIv3B. 10, The p\ilinonary artery. II, The branch to the rifsht lung. 12, The branch to the left lung. 13, The right pulmonary vein. 14, The left pulinonmy vein. 15, The left auricle. 16, The left ventricle. 17. TIm mitral valves. yote. Let a /eview of the anatomy and physiology of the respiratory organs be given from figs. 5'S, f)\), or fiom outline anatomical plates 5 and 7 9 98 ANATOMY, PHYSIOLOGY, AlsD HYGIENE. CHAPTER XXI. HYGIENE OF THE RESPIRATORY ORGANS 267. For man to enjoy the highest degree of health, it is necessary that the impure " venous " blood be properly changed. As this is eftected in the lungs by the action of the air, it follows that this element, when breathed, should be pure, or contain twenty-one per cent, of oxygen to about seventy-nine per cent, of nitrogen. 268. The quality or purity of the air is affected by every respiration. The quantity of nitrogen is nearly the same in the expired, as in the inspired air. But the quantity of oxygen is diminished, and that of carbonic acid is increased. Thus, every time we force air from the lungs, it becomes unfit u> be breathed again. Experiment. Sink a glass jar that has a stop-cock, or one with a glass stopper, into a pail of water, until the air is expelled from the jar. Fill the lungs with air, and retain it in the chest a short time, and then breathe, into the jar, and instantly close the stop-cock. Close the opening of the jar that is under the water with a piece of paper laid on a plate of sufficient size to cover the opening, invert the jar, and sink into it a lighted candle. The flame will be extinguished as quickly as if put in water.* • As a aubatitute for a jar with a stop-cock, take a piece of lead pipe bent in the form of a siphon, and insert it in the mouth of a reversed J£ir. This experiment is as conclusive whether the air is in- h;ilcd once only, or breathed many times. 267 — 285. Give the hygietw of the respiratory organs. 267. What is ne- cessary that man may enjoy the highest degree of health ? AVhat propor- t'on of oxygen and nitrogen should the inspired air contain ? 268. What iB the differrtnoe bet^veen inspired and expired air ? How can this differ- ence be shown i HYGIENE OF THE RESPIRATORY ORGANS. 99 Remove the carbonic acid by inverting the jar, and place i lighted candle in it, and the flame will be as clear as when out of the jar. ObservaHon. It is familiarly known that a taper will not burn where carbonic acid exists in any considerable quantity, or when there is a marked deficiency of oxygen. From this originated the judicious practice of sinking a lighted candle into a well or pit before descending into it. If the flame is extin* (juished, respiration cannot there be maintained, and life would be sacrificed should a person venture in until the noxious air is removed. 269. Air, in which lamps will not huin with brilliancy, is unfitted for respiration. In crowded rooms, which are not ventilated, the air is vitiated, not ouly by a decrease of oxygen and an increase of carbonic aci