THE LIBRARY OF THE UNIVERSITY OF CALIFORNIA PRESENTED BY PROF. CHARLES A. KOFOID AND MRS. PRUDENCE W. KOFOID Vy ~ VRATIVE AND HUMAN; IN WHICH ARE DESCRIBED THE MECHANICAL, ANIMAL, VITAL, AND SENSORIAL ORGANS AND FUNCTIONS ; ALSO, THE APPLICATION OF THESE PRINCIPLES TO MUSCULAR EXERCISE, AND FEMALE FASHIONS AND DEFORMITIES. INTENDED FOR THE USE OF SCHOOLS AND HEADS OF FAMILIES. TOGETHER WITH A SYNOPSIS OF HUMAN ANATOMY. ILLUSTRATED BY NUMEROUS ENGRAVINGS. ~By J. L. r]i|TM'Fj'Tfip'iri M jj. AUTHOR OF "MINERALOGY," "NA'T^RAL PHILOSOPHY," "CHEMISTRY," "BOTANY," "GEOLOGY," &c. REVISED EDITION. NEW-YORK: PUBLISHED BY PRATT, WOODFORD & CO. 1848. "- '' ' Entered according to Act of Congress, in fhe year 1847, by J. L. COMSTOCK, in the Clerk's Office of the District Court of Connecticut. 01 PREFACE. PERHAPS the author -" the following work cannot do better than to make an CA ^t or two, by way of Preface, from Dr. DICK, "On Mental Illumination and Moral Improvement," in which he has shown the want of, and the advantages to be de- rived from, a treatise on Comparative and Human Physiology 'or the instruction of youth. That a work on these subjects is -varied, it is believed every intelligent instructor is ready to ac- knowledge ; and whether that here offered to the public will serve the required purpose, must now be submitted to the judg- ment of others. "It is somewhat unaccountable," says Dr. DICK, "and not a little inconsistent, that while we direct the young to look abroad over the surface of the earth, and survey its mountains, rivers, seas, and continents, and guide their views to the regions of the firmament, where they may contemplate the moons of Jupiter, the rings of Saturn, and thousands of luminaries placed at im- measurable distances, — * * that we should never teach them to look into themselves, to consider their own corporeal structures, the numerous parts of which they are composed; the admirable functions they perform ; the wisdom and goodness displayed in their mechanism, and the lessons of practical instruction which may be derived from such contemplations." Again, the same author, speaking of subjects for Natural The- ology, enumerates " particularly, the curious and admirable mech- anism displayed in the construction of animated beings, from the microscopic animalcula, ten hundred thousand times less than a visiblej^pfnt, to the elephant and the whale — the organs of mas* ticatitoljj, deglutition, digestion, and secretion, all differently con- triver, according to the structure of the animal, and the aliments on''which they feed — the eyes of insects, and the thousands of transparent globules of which they consist — the metamorphoses of caterpillars and other insects, and the peculiar organization adapted to each state of their existence — the numerous beauties, and minute adaptation in the wings, feet, probosces, and feathers, of gnats and other insects — the respiratory apparatus of fishes, and the nice adaptation of their bodies to the watery fluid in which they pass their existence — the construction of birds, their pointed bills to penetrate the air, their flexible tails serving for -udders, the lightness, strength, and tenacity of their feathers, * PREFACE and the whole structure of their bodies adapted to the air in which they fly, and the food by which they are sustained— above all, the wonders of the human frame, the numerous parts of which it is composed; the hundreds of bones and muscles, the thousands of veins and arteries, glands, nerves, and lymphatics — the heart with its ventricles and auricles, the brain, "with its in- finity of fibres, the lungs with their millions of vesicles, * * * — these and thousands of similar objects, adaptation and con- trivances which appear throughout every part of the universal system." " One great practical end," says he, " which should always be kept in view in the study of physiology, is the invigoration and improvement of the corporeal powers and functions, the preser- vation of health, and the prevention of disease." All these, and many other subjects of a similar nature, are noticed in this volume, and if the author has succeeded in adapt- ing his language and manner to the understanding of youth, he cannot but hope that this treatise will be the means of greatly increasing the knowledge of the rising generation in one of the most interesting and useful departments of natural science; and at the same time of directing their attention, especially that of females, to the preservation of their forms and their health, by avoiding habits and fashions, which at once deform their persons and ruin their constitutions. • To avoid the necessity of frequently quoting authorities, we subjoin a list of authors which have been consulted in the prog- ress of the more strictly physiological part of this work ; the ap- plication of these principles toward the sequel, being chiefly the original suggestions of the author. Among the authors consulted, we are especially indebted to the " Bridgewater Treatise on Animal and Vegetable Physiol- ogy," by Dr. Roget. From this, much matter and many cuts have been taken. Dr. Ticknor, " On the Philosophy of Living," Harpers' Fam- ily Library, No. 77, contains a mass of sound and valuable ob- servations on many of the various subjects on which it treats, but was unknown to the author until too late for him to take much advantage from the matter it contains. Dr. Alcott's little book, " The House I live in," is an original and curious treatise, and is well calculated to arrest the attention of children, and to instruct them with respect to the structure of their bodies. Dr. Combe's Physiology, No. 77, Harpers' Family Library, is a highly valuable and sufficiently popular work on the subject, and ought to be read by every parent and school-teacher. HARTFORD, Connecticut, July, 1836. CONTENTS PAGE PHYSIOLOGY EXPLAINED . . 9 PAGE Ingenuity of Insects, . . 66 Caddis Worm, .... 68 PART I. PART II. MECHANICAL FUNCTIONS 12 Sponsre, . • 12 VERTEBRATED ANIMALS, . 71 ""\^.j Polvpiieraj ...» 15 Animals resist heat and cold, . 72 Hydra . ... 18 Structure of the bones, . . 76 Pennatulae, .... 20 Formation and growth of bone, 79 Infusoria, . ... 22 Spine of the vertebrata, . . 80 Wheel Animal, . i 23 Form of the vertebrata, . . 81 Portuguese Man- of- War, . 24 Skeleton of the human trunk, Sea Urchin, . . ... 25 and arms, .... 82 26 Unity manifested in the spines, 84 Acephala, .... 27 Mechanical elements 01 the Cardium, .... 29 vertebrae, .... 85 Cuttle-fish, . 30 Vertebrae of Fish, ... 86 31 Locomotion of Fishes, . . 87 31 Spines of Birds and Fishes, . 91 Lobster, ..... 32 Skeleton of the Swan, . . 91 Process of casting the shell of, 32 Comparison of the bones of Men and Birds, . : 92 Insects, 34 Changes in the forms of Insects, 34 PART III. Silk- Worm, .... 36 Metamorphoses of Insects, 37 ANIMAL FUNCTIONS, . . 93 Larvae that feeds on the parsnip, 38 Sources of Nutrition, . . 94 Butterflies :md Moths, 40 Vegetable Food, ... 94 Change from Chrysalis to Butterfly, .... 41 Animal Food, 94 Relation between animals and Wings of the Butterfly, how their food, .... 96 expanded, .... 43 Man Omnivorous, ... 96 Scales on the wings, . . 44 Red drops emitted by Butter- flies, Ancient showers of Blood, 45 46 Animal Nutrition, ... 97 Complexity of Stomach in the high orders, ... 98 Tusseh Silk- Worm, 60 Man eats everything, . . 98 Beetles, Blind Beetles, .... 51 Grinding of Food. ... 99 52 Grinding in the Lobster, . . JOS White Worm, .... 62 Gizzards of Birds, . . • 100 55 58 Orfrnna of nutrition a/n.A viitnl. Structure of Insects, 60 ity in the Mammalia, . 102 Plan of the most important Insects walk by atmospheric pressure, « Viscera, . 103 64 [Circulation of the blood, . 105 CONTENTS. PAGE FA&K Mastication, 106 Respiration in Birds, 146 Teeth of Man, 107 Lungs of the Ostrich, . 147 Teeth of the Tiger, 108 Teeth of the Antelope, 109 Teeth of the Rat, 110 Respiration of the Mammalia, 149 Masticating Organs of Man and the Mammalia, 110 Respiration in Man, Trunk of the Human Skeleton, 149 150 Situation of the Diaphragm, 151 Organs of Digestion, . Human Stomach, . 112 112 Human Lungs and Heart, Chemical Effects of Respiration, 152 153 Gastric juice, 113 Animal Heat, 155 Chemical Effects of the Gas- tric Juice, . 114 PART V. Comparative Digestion, Stomach of the Sheep, . Rumination, .... 115 115 117 SENSORIAL FUNCTIONS, . Brain and Nerves, Nervous Ganglions, 156 156 158 Relation of the Horns and Stoniucli • • 117 Vision, 159 Water cells in Camels' Stom- 117 Structure of the Human Eye, Structure of the Iris, 159 161 Water Cells in Elephants7 Stomach, .... 118 Physiology of Vision, . Cause of the inverted Image, 162 166 Food of Man and other Ani- mals, ..... 119 Motions of the Eye, . 169 Elements of Nutrition^ . Food nutritive and digestible, Man requires a variety of 119 119 Magnitudes and Distances, . Insensibility to certain Colors, Comparative Physiology of 170 173 food, . . . . 120 Vision, .... 174 Dr Stark's Experiments, Dr. Magendie's Experiments, Dr. Cooper's Experiments, . 121 Eyes of Insects, . 122 Eyes of Fishes, 122 Eyes of Birds, . . « 175 178 179 Dr. Beaumont's Experiments, 123 Audition, or Hearing, . 181 PART IV. Auditory Organs in Man, 183 Bones of the Ear, 186 CIRCULATION OF THE BLOOD, Circulation in Insects, . Circulation in the Frog, Circulation in Fishes, . Circulation in warm-blooded Animals, .... 127 Physiology of Hearing, 1*8 Comparative Physiology of 1^9 Hearing, .... 130 Hearing in the Lobster, Hearing in the Frog, Hcunnj? in BircJs* * • • 188 189 190 190 192 Two Hearts separated, 132 Musical Ear, 193 Two Hearts united, 132 Musical Ear situated in the The two Hearts act together, 134 Brain, .... 195 Number of Pulsations of the Heart, .... 134 Organs of Smell, 196 Effects of Alcohol on the Cir- culation .... Olfactory Nerves in the Duck, 135 Audubon on the Smell of Vul- 197 Alcohol not the Product of t n»»£ic 198 Distillation, Muscular force of the Heart, 136 138 Organs of Smell in Fishes, . 199 Organs of Taste, . . 200 Respiration, .... Respiration in the Oyster, . 139 140 Organs of Touch, . . * 201 Respiration in Fishes, . 141 PART VI. Respiration in the Lamprey, 142 MENTAL AND PHYSICAL Ex- Atmospheric Respiration, . 142 203 Respiration in Insects, 143 Respiration in Reptiles, Respiration in the Frog, J44 145' The Brain, .... Size of the Brain, . 203 204 Phrenology, .... Phrenology wants more facts, Roget's Opinion, . Bostock's Sentiments, . . Double Organs, Susceptibility of the Brain, . The Muscles, Action of the Muscles depend on the Brain, Muscular Contraction, . Mechanism of the Muscles, Muscular Action of the Arm and Hand, Motions of the Fingers, Connexion between the Ner- vous and Muscular systems, Temperament and Disposition, Force of Muscular Ccnlraction, Thomas Topham, Increasing the Muscular Pow- Practical Inferences from the foregoing Principles, Connection between the Brain and Muscles, Muscular Exercise of the Cler- gy and other Literary Men, Obvious Effects of too much Mental Labor, . Clergymen not allowed Exci- ting Exercise, . Men incapable of constant Mental Labor, . Former Condition of the Clergy, Different Effects of Exercise, Muscular Exercise requires cerebral Excitement, Dr. Darwin's Case, Nature requires exciting Exer- cise, ..... Men bound to use such Exer- cise as conduces to Health, Effects of incessant Mental Labor, .... Mere Attention to Diet of lit- tle Use, . Cheerfulness a Remedy, Laughing a proper Exercise, Different Kinds of Muscular Exercise, . Manual Labor, Scientific Excursions, Field-Sports, Angling, Riding, . , CONTENTS. 7 PAGE PAGE 205 206 207 Exciting Exercise absolutely necessary to the Studious, Sir Walter Scott an Example, 255 256 207 213 214 Physical and Mental Educa- tion of Youth, . 258 216 Consequences of confined Posi- tion of Females at School, 259 Remarks of Dr. Combe, 260 216 Remarks of Dr. Dick, • 263 216 Callisthenics, . . „ . 266 217 266 Selection of Bows and Ar- 218 rows, 268 221 General Considerations with respect to Health and Dis- 223 272 226 Small-Pox, .... 274 227 Fever and Ague, . 274 228 228 Anson's and Cook's Voyages, Spanish Squadron, Cook's Second Voyage, 275 276 277 Precautions with Respect to 231 Youth, .... 280 231 Predisposition to Consumption, Exercise of the Lungs, 280 282 232 APPENDIX. 233 DESCRIPTION OF THE ATTI- TUDES, .... 286 234 Standing, 285 235 The Foot, . 287 236 237 Walking, Pedestnanism, 292 290 Sitting, . 290 238 .238 Causes of Spinal Curvatures, Sitting Postures described, 291 293 Leaning Posture, . 294 239 Dress a Source of Deformity, Fashionable Deformity, 296 297 240 Effects of Pressure on the Mus- cles of the Back, 298 241 Application of these Princi- 100 242 Effects of Tight Lacing on 243 the Lungs, 304 245 Pulmonary Consumption in Consequence of Pressure on the Lungs, . . . 307 247 Dr. Morton's Case, 309 247 247 Mortality by Consumption, . Prevention of Spinal Distor- 312 247 tion, 312 250 252 ) Effects of Stays on the Vigor of the Species, . 318 Books consulted with reference to this Work. Arnott's Elements of Physics. Bostock's Physiology, 3 vols., London. Blumenback's Physiology. Magendie's Physiology, Edinburgh. Dunglisson's Physiology. Library of Useful Knowledge. Cuvier's Animal kingdom, 4 vols. Combe on Health and Mental Education. Ticknor on the Philosophy of Living. Bingley's Animal Kingdom, 4 vols., London. Parkinson's Organic Remains. London. Roget's Animal and Vegetable Physiology, 2 vols., London. Fyfe's Anatomy 4 vols., London. Bell's Anatomy, 2 vols. Hooper's Medical Dictionary. Spallanzani's Dissertations on Natural History, 2 vols., London. Brown's Book of Butterflies, 2 vols., London. Combe on the Physical Constitution of Man. Dick's Christian Philosopher. Dick's Mental Illumination. Alcott's House I live in. Bell on the Hand. Letters on Entomology. London. Lizar's Plates of the Human System, folio, London. Beaumont on Digestion. Kirby's History of Habits of Insects. ' Shaw on Dislocations of the Spine. London. Jardine's Library of Natural History. Edinburgh. Natural History of Insects, 2 vols. [Harpers' Family Library.] Rennie's History of Insects. 3 vols. Hayward's Outlines of Human Physiology. Morton's Illustrations of Consumptive Diseases. Kitchiner's Invalid's Oracle. [Family Library.] Habits of Birds. [Library of Entertaining Knowledge], London Willich's Lectures on Diet and Regimen. Brewster's Letters on Natural Magic. Bichat on Life and Death. Rennie's Alphabet of Insects. London. Barry on Digestion. London. Ure's Chemical Dictionary. ANIMAL PHYSIOLOGY THE term PHYSIOLOGY, signifies " a discourse on Nature," smd hence is applicable to an explanation of the laws which govern the growth of vegetables, and the crystalliza- tion of minerals, as well as to a discourse on the functions of animal life. Animal Physiology is divided into two distinct depart- ments, namely, comparative and human. Comparative physiology, is a discourse or treatise on the corporeal func- tions of the inferior animals. Human physiology explains the corresponding i^etions of man. In pursuing the subject of animal physiology, the student will constantly be reminded that nothing has been left un- done, even to the minutest detail, which could in any way advance the welfare and comfort of living existences, taken as a whole. On the contrary, he will find that each animal is placed in a situation most congenial to its own organization and capacities, and that it is provided with instruments, and endowed with senses and capabilities ex- actly befitting the condition in which it is placed. The earthworm, for instance, has no use for eyes, since it never voluntarily comes to the light ; nor for hands or wings, since these would be worse than useless in the place and manner of its existence. Nor has the fish any use for lungs or feet, since its organization prevents it from breath- What is the meaning of the term physiology? How is animal physiol- ogy divided ? What is said of the adaptation of the organs and capacities of animals to their wants ? 10 ANB&LAL PHYSIOLOGY. ing the air or walking on the earth. On the contrary, sight, instruments for rising in the air, and for walking on the earth, are absolutely necessary for the higher orders of animals, otherwise they would be unable to accomplish the ends for which they wrere created. The student will also be able to notice, that the Creator has employed the strictest economy with respect to animal organization, every individual being in possession of all the instruments and means with which to accomplish the ends of its creation, but no more. No superfluous organs are bestowed on an)", even of the favorites of nature, but always a sufficiency for every destined purpose, both with respect to number and power. In the details of the habits and physiological functions of some of the lower orders of insects, the pupil will probably often find himself greatly excited by curiosity, but it is hoped that he will not therefore neglect or forget the chief design of this work, which is to bring him to the acknowledgment and adoration of a Great First Cause, by making him acquainted with the mechanism and functions of his animated creation. What is said with respect to the economy employed in animal organi- zation? PART I. MECHANICAL FUNCTIONS 1. THE lowest orders of the animal creation possess neither bones, nerves, sight, nor hearing. Some of them are fixed, while others have the power of locomotion, though they possess neither eyes nor ears to direct them in their movements. 2. Some of the medusa tribes can hardly claim the rank of organized beings, appearing when alive like a trans- parent jelly, and when dead leaving nothing but a lim- pid watery fluid into which they dissolve by decomposi- tion. 3. The sponges have no higher place as animal exist- ences, being fixed to the bottom of the sea, and having no sensation and no motion, except that by which they obtain their food. 4. Many other orders, as the hydra, vorticella, and in- fusoria, are but little removed from these in organization or capacity. Some of these tribes are so little above vegetables in their organization, that they may be pre- served like the seeds of plants. The rotifer, or wheel animal, which lives and moves in water, may be taken out and dried, when it appears like a grain of dust, and may so be kept for any length of time. But if placed in a drop of water it soon shows its vitality by its brisk voluntary motion, and this alternate life and death the What is said of the senses of the lowest orders of animals ? What is said of the medusa? What is said of the sponges? What is said of the rotifer or wheel animal ? 12 MECHANICAL FUNCTIONS. little animal passes through any number of times without injury. In like manner the gordius, a worm resembling a horse-hair, which inhabits stagnant pools, may be dried, when it has no more signs of life than a piece of wire, and again revived to life by immersion in water. This animal is supposed by many to have derived its exist- ence from a horse-hair accidentally falling into the water. But it is hardly necessary to say that such mis- takes call for a more general knowledge of animal Phys- iology. 5. We shall begin our physiological descriptions with the most simple organizations, and gradually passing through those which are more and more complex, finally come to that of our own species. SPONGE. 6. The remains of this animal are in such universal use, and consequently so well known, as to require no general description. It belongs to an order of animals called zoophytes, which also includes the corals, the polypi, and several other races which are only a single grade above vegetables. This order indeed appears to be the connecting link between the animal and vegetable king- doms. The term zoophytes signifies " animated plants." 7. The sponges of which there are many species, are all marine animals, living at the bottom of the sea, where they are firmly attached to rocks and stones. 8. These productions in general appearance much more nearly resemble plants than animals ; but in their internal organization and structure they diifer entirely from vegeta- bles. Their animal nature is clearly shown by chemical analysis, and by the voluntary motion of some of their parts which resemble respiration. 9. Every part of the surface of a living sponge presents to the eye two kinds of orifices ; the larger having a rounded shape, and generally a little raised on the mar- What is said of the gordius? To what order of animals does the sponge belong? What is the meaning of the term zoophytes ? How is the animal nature of the sponge indicated ? What is said concerning the orifices of the living sponge ? SPONGB 13 gins ; the smaller are much more minute, running in all directions, and constituting what are termed the pores of the sponge. Fig. 1. 10. The structure of the living sponge is shown by Fig. 1, where it will be observed that the larger orifices are much more conspicuous than in the dead one, these elevated parts being usually almost obliterated by the death of the animal, and by pressure in packing it for market. 11. From these orifices, Dr. Grant has discovered that in the living sponge there is a constant stream of the fluid in which the animal is immersed. A small piece of liv- ing sponge being placed in a watch-crystal filled with sea-water, and the whole placed under a microscope, Dr. Grant perceived some motion among the opaque particles of the fluid. " On moving the watch-glass," says he, " so as to bring one of the orifices on the side of the sponge fully into view, I beheld, for the first time, the splendid spectacle of this living fountain, • vomiting forth, from a circular cavity, an impetuous torrent of liquid matter, and hurling along, in rapid succession, opaque masses, which were strewed everywhere around. The beauty and novelty of such a scene, in the animal kingdom, long arrested my attention, but after twenty- five minutes of constant observation, I was obliged to withdraw my eye from fatigue, without having seen the torrent for one instant change its direction, or diminish, in the slightest degree, the rapidity of its course. I con- What was the experiment by which Dr. Grant proved that sponge is ail 14 MECHANICAL FUNCTIONS. tinued to watch the same orifice, at short intervals for five hours, sometimes observing it for a quarter of an hour at a time, but still the stream rolled on with a con- stant and equal velocity." 12. The water thus poured forth in a perpetual stream from these apertures, is received through the millions of pores which pervade the sponge in every direction, and by this means it is that the animal is nourished. Even fish of several pounds weight will live for weeks, or per- haps months, upon no other nourishment than what is con- tained in sea-water, so that the sustenance of the sponge by such means presents nothing, uncommon. 13. The mechanism by which these currents of water are constantly produced, is involved in obscurity. It is, however, supposed to consist of cilia, or small hairs lining the inner surfaces of the tubes, the motions of which propel the water through them. 14. These currents are readily made apparent by pla- cing the living animal in a shallow vessel of sea-water, and strewing a little powdered chalk on the surface, the mo- tions of which makes that of the water plainly visible, as shown in the figure. 15. Manner in which the young sponges are dissemi- nated. In all parts of creation, whether in the vegetable or animal kingdoms, there is provided effectual means for the dissemination of the species. (For an account of the dissemination of the seeds of plants, see the author's Intro- duction to Botany.) For the distribution of the sponges, the method provided is singularly curious and interesting, and at the same time displays, in a most striking manner, the care which the Creator has taken to perpetuate his most humble works. 16. On examining certain parts of the sponge, which, when living and wet, are nearly transparent, there is found a multitude of yellow, opaque spots, visible to the naked eye. These, when examined with a microscope, Whence comes the water which is poured forth from these apertures ? How does the sponge obtain its nourishment? By what means is it supposed the current through the apertures are produced? How are the currents made Apparent ? In what manner are the voung sponges distributed? POLYPIFERA. are ascertained to be the eggs, or gemmules of the fu- ture animal. In a few months they enlarge in size, and assume an oval, or pear-shaped form, and Fig. 2. are covered with cilia, or hairs, as shown by Fig. 2. They then become detached from the parent, one after another, and float or swim along with the current, always carrying their broad and rounded extremity forward. While thus suspended in the water, the cilia, with which they are cover- ed, are in rapid and perpetual motion, giving them a slow impulse forward. In these movements if they strike against each other, or meet with any other im- pediment, they avoid the difficulty as other animals do, by turning aside and then proceeding in their former course. In some instances when two of these little animals happen to meet, they adhere to each other, and in a few days no line of distinction can be observed be- tween them, the two being united into one individual, and so continue to grow during the rest of their lives. This union appears to be analogous to that of engraft- ing in plants, only with respect to the young sponges it is voluntary. 17. After leaving the parent, these little animals float about for a day or two, when finding a suitable place, they fix themselves firmly to a stone or rock, and there gradu- ally increase to the adult size, and in their turn send forth their progeny as above described. 18. These facts, of course, could only have been ascer- tained by placing the parent-sponge in a vessel of sea- water. Many of these observations were made in vessels no larger than watch-crystals. POLYPIFERA. 19. The term polypifera is the name of the order, and means animals bearing polypi. The name polypus In what manner do they move through the water? What is said of the union of two of these animals into one? What does this union ap- pear to be analogous to? What becomes of the young sponges after being detached from their parents? What is the meaning of the term polypifera? 36 MECHANICAL FUNCTIONS. denotes a mass of these animals, and polype, a single animal. 20. This order embraces many species of very simple animals, chiefly inhabiting salt water. Some of them are exceedingly minute, while others are several inches in length. 21. Each of these curious animals is formed of a tube, attached by its lower end to some solid substance, the upper end being surrounded by a number of flexible fibres, or arms, called tentacula. These tentacula radi- ate from a common centre, in the midst of which is the mouth of the animal. A single polype is represented by Fig. 3. The tentacula are eight in number, Fig- 3. but in some species are much more numerous. The arrangement of these, on the margin of the mouths of the animals, bears a considerable re- semblance to a flower with radiating petals, as the daisy and aster. 22. Polypi for the most part reside in cells, or tubes, composed of horny or alcareous matter, in the form of sheaths, which enclose the body of the animal, leaving the tentacula and mouths free for action above their margins. Sometimes these tubes are joined to- gether endwise, like the branches of a Fl£; 4- tree, leaving lateral apertures for the pro- tusion of the tentacula of each animal, as shown by Fig. 4. In this figure each bundle of radiating fibrils along the branches represents the tentacula of a polype. 23. The well-known marine substance called coral is the product of the la- bors of certain species of these indus- trious animals. A great number of species are perpetually employed in the construction of different varieties of this substance. Coral is composed of calcareous particles, with a portion of animal, and occasionally coloring matter elaborated into a solid, or porous form, by these animals. What does polype mean? Polypus? Polypi? Describe a polype? What are teutacula? What common flowers do these animals resemble ? What does Fig. 4 represent? POLYPIFERA. 17 Fig. 6. 24. A branch of red coral is represent- Fis- ed by Fig. 5, with the little animals at work on it. 25. Fig. 6 is a part of one of these branches magnified, and showing the tentacula expanded, as when the animal is under water ; and also in the contract- ed state, as when the branch is removed from the fluid. 26. These structures are fixed perma- nently to stones or rocks at the bottom of the ocean, which in warm climates are often covered with them to a great extent. 27. It has been ascertained that these fixed zoophytes are multiplied like the sponge by gemmules, in the manner simi- lar to that already described. 28. The mechanism by which some species of polypi produce a constant current of water toward their mouths, is so curious, that we should not do justice to this subject without describing it. 29. When the tentacula are expanded, small particles in the water may be observed constantly tending toward the mouths of these animals. This motion of the water is not produced by the motion of the tentacula themselves, but is the effect of the rapid vibration of minute cilia placed along their sides. 30. In the species calledflustra carbacea, the tentacula in each polype are twenty-two in number, and along the lateral margins of each, there Fig. 7. Fig, 8. is a single row of cilia extend- ing from the base to the ter- mination. . This animal is rep- resented in the posture of forming the current by Fig. 7. f§/, Fig. 8 is a portion of a tenta- cula highly magnified, to show the cilia, and the manner in which the current is produ- ced. From the positions in 2* 18 MECHANICAL FT/NOTIONS which the cilia stand, it will be observed that their mo- tions are ascending on the one side, and descending on the other. By these contrary motions, the water would be carried around the tentacular in a longitudinal direc- tion, provided it was detached. But many of them being placed around the mouth of the polype, with the motions of the cilia on the outside ascending, and those on the inside descending, it is obvious that the effect is to pro- duce a perpetual current of the fluid to the mouth of the animal, and as the polype subsists on minute insects, and particles of decomposing matter which it takes from the water, this wonderful mechanism is evidently designed to bring food to its mouth. 31. The vibrations of these cilia, when the animal is vigorous, are too rapid to be distinguished by the eye, even when assisted by a microscope ; and it is only when it becomes languid, and the motions diminished, that they can be -seen. But the effect can be discovered by the naked eye, by the motions of floating particles in the water. HYDRA. 32. To the zoophytic order belong another tribe of animals called hydra, which, on some accounts, are the most singular and curious productions of nature. This animal consists of a stomach with tentacula for catching its food, and nothing more. It exhibits not a trace of either brain, nerves, or organs of sense of any kind ; nor is there any parts corresponding to lungs, heart, arteries, or veins, or any other vessels whatever ; all those organs so essential to the existence of other animals, being en- tirely wanting. 33. Mr. Trembley, of Geneva, who watched the actions of these animals with unwearied patience, for" days to- gether, has given the following curious account of what he discovered. What ornamental substance is made by polypi? What is composi- tion of coral? In what manner are polypi multiplied? Explain Figs. 7 and 8. In what manner do polypi produce a constant current of water toward their mouths? What purpose does this current answer to the animal? What parts pertaining to other animals are wanting in the hydra? HYDRA, 19 34 The hydra are fresh-water animals of very diminu- tive size, and are generally fixed to some solid body, as a stick or leaf, by the tail, though they have the power of detaching themselves, and of moving slowly through the water. They are carnivorous animals, and though they do not chase their prey, they devour all kinds of liv- ing creatures coming within reach of their tentacula, which they can manage. Worms longer than themselves they devour, by first doubling them together by means of their long arms. 35. A hydra in the act of gorging a worm of twice its own size, is seen at Fig. 9. The poor worm is completely entangled within the folds of the tentacu- la, while the voracious animal, with ex- panded mouth, is absorbing its juices, so as to bring it with- in the capacity of himself. 36. It sometimes happens that when two of these ani- mals have seized the same worm by different ends, a vio- lent struggle ensues between them, and the stronger, having gained the victory, not only swallows the object of contention, but his antagonist along with it. F- 1Q Fig. 10 represents such a case, the tail of the swallowed animal protruding from the mouth of the victor. But the former soon extricates himself from this dilemma, without having suf- fered the least injury, and indeed is often the gainer, by retaining a portion of the object of contention to himself. 37. But the most singular, and indeed, astonishing facts, which Mr. Trembley ascertained with respect to these ani- mals, are, that they 1mn±e the power of repairing all sorts of injuries and mutilations inflicted on them, and of still digesting their food, and of recovering a good degree of health after being turned wrong side out. 38. If their tentacula be clipped off they soon grow again. If the animal be cut in two, across the middle, there will sprout forth a new head from one part, and a new tail from the other, together with such portions of the body in each case as were wanted to make a good and What is said of the power of the hydra to reproduce mutilations * 20 MECHANICAL FUNCTIONS. complete animal. If the head of the hydra and a por- tion of the body be divided by a longitudinal section, the animal is thereby the gainer, for the divided parts form t^'o b-ods instead of one. with complete sets of tentacula for each mouth, and thus he can enjoy the sat- isfaction of eating with two mouths at the same time. If the head be split into half a dozen parts, each part will form a new head with mouth and tentacula to match, the whole being united to one body. Fig n Fig. 11 represents a seven-headed mon- ster, the result of several mutilations and divisions of one of these protean creatures. 39. Sometimes of its own accord a hy- dra will split in two parts lengthwise, each division becoming independent of the other, and growing to the same size, and attaining the same organs as the original animal. 40. Mr. Trembley also found that any portion of one hydra might be engrafted on another, in the same man- ner that pieces of India-rubber may be joined, that is, by cutting their surfaces and pressing them together. By this means they would unite and become a compound animal. Thus many heads may be united to one body, or many bodies to one head ; and so, on the contrary, when one hydra is introduced into the mouth of another, so that their heads are kept in contact, for a time, they unite and become one individual animal. 41. Even the figures of other animals, as quadrupeds, or man, might be constructed in this manner, though every- where covered with moving tentacula. PENNATUL.E. 42. Another form under which polypi exist, is that call- ed pennatidce. This is called sea-pen, from its resem- How many parts of these animals may be engrafted upon each other* Give some account of the pennatulae. PENNATmJK 21 Fig. 12. blance to a quill. It consists of a calcareous stem, the upper end of which has a series of branches on each side, resembling the filaments of a feather, and in the end of each of which resides an animal, the whole being represented by Fig. 12. Some of the polypi are seen magnified m Fig. 13. 43. These animals are not fixed like those we have described, but float along with the currents of the ocean, having little or perhaps no power of locomotion, though the movements of their tentacula are sufficient to prevent their sinking, and to enable them to rise slowly in the water. 44. The pennatulse must be considered as a mass of. dis- tinct animals aggregated together to form, in many respects, one individual. In Botany, the class syngenesia presents many distinct flowers assembled together to form a single compound individual, as the thistle and dandelion, each individual being on the same receptacle, and supported by the same stem. So far, therefore as aggregation is concerned, there is a strict analogy between a compound flower and the pennatulse. But while each individual of the syngenesian flowers receives its nourishment through the same stem, the corresponding part of the compound animal, which is a common stomach, receives its nourishment through hundreds of mouths, so that here the analogy fails. 45. In the pennatulae, each mouth leads into a separate stomach, whence the food, after digestion, passes into several channels, which proceed in different directions from the cavity of each stomach, dividing into many branches, and being distributed over all the surrounding portions of flesh. These branches communicate with sim- ilar channels proceeding from the neighboring stomachs ; What is said of the stomach of the pennatulae ? XX MECHANICAL FUNCTIONS. so that the food which has been taken in by one of the mouths, contributes to the general nourishment of the whole mass of aggre- Fig. 14. gated polypi. These curious facts were dis- covered by Cuvier, and are represented by Fig. 14, where the stomachs of the three polypi, with their ten- tacula spread out, are seen communicating at their lower extremities with a canal, which thus, becomes a common stomach to the whole colony. INFUSORIA. 46. The infusory insects, or infusoria, were so named from the circumstance, that they always appear during the warm seasons, in water in which vegetable or animal sub- stances have been infused. Hence they exist in stagnant ditches and pools of water, everywhere during the summer and autumn. These animals are generally too minute to be distinguished by the naked eye, and therefore it is to microscopic observations that we owe our knowledge of their existence and habits. 47. Former writers on natural history, have called these animalcula, monads, and have regarded them as occupying the very lowest rank of animal creation. Some have even expressed doubts whether they really belong to the animal kingdom ; but would rather consider them as molecules, or the elementary particles of organic beings, separated from each other by chemical decomposition, but retaining the power of voluntary motion. 48. The infusoria, during the last century, have been the object of very laborious microscopical research ; no naturalist considering himself accomplished until he had spent a considerable portion of time in observing the motions and studying the characters of these animated particles. Many theories, conjectures, and disputes, Whence do the infusoria derive their name ? What was the former name for infusoria? INFUSORIA. XO arose in consequence of such observations; some con- tending that monads were merely living globules wit - out animal organization, but capable of uniting into ani- mated masses, and thus of forming the flesh and blood of organized creatures. According to this doctrine, all other animals, including us, human beings, are nothing more than great congregations of monads. That great naturalist, Buffon, was the author of this hypothesis, and therefore it is hardly necessary to say that it had many profound advocates. It would neither interest nor in- struct the student in physiology to give a detail of other opinions concerning these living motes, since the more perfect microscopes of later philosophers have shown that these animals are regularly and carefully organized, having not only a stomach, but such other organs as fit them for their station in life. 49. Wheel Minimal. — The rotifera, or wheel animalcula, is one of the infusoria race, though F'g- I5- larger than the monad. Fig. 15 rep- resents an animal of this order, mag- nified 380 times its natural size. Its name is derived from -the apparatus which it possesses for creating a cir- cular current in the water. The or- gans by which this effect is produced are two in number, and are seen at the top of the figure. They are situ- ated on the head, but do not surround the mouth, like the tentacula of the polypi. They consist of circular disks, the margins of which are fringed with rows of cilia, bearing a resemblance to a crown wheel in machinery. These wheels appear to be incessantly revolving, and generally in one direction, giving to the fluid a rotary impulse, which carries it around in a con- tinual vortex. The constancy of this motion would seem to indicate that it is as necessary to the life of the animal as respiration is to the higher orders ; the revolu- What was the opinion of Buffon with*respect to monads ? What peculiarity do the rotifera exhibit ? Is the revolution of the wheel of the rotifera real, or only apparent' 24 MECHANICAL FUNCTIONS. tions never ceasing so long as the animal is alive. This motion, when considered merely with respect to the mechanism by which it is produced, cannot but excite intense curiosity ; for we have no analogy in the organi- zation ef any other animal with which to compare it, nor from all we 'know on the subject should we believe it possible that a circular motion of a part of an animal could be continued for any length of time in the same direction. What animal or other substance will with- stand perpetual twisting in one direction? and yet if there is no deception with respect to the revolutions of these wheels, one would be led to suppose such a sub- stance. The J appearance is undoubtedly that of a con- stant revolution of the wheel itself, but recent observers, however, believe it to be only apparent, and the decep- tion to be caused by a peculiar and exceedingly rapid motion of the cilia on the margin of the wheels. 50. Phy salia, or Portuguese Man-of-War. — This animal greatly excels in size those we have heretofore described, but scarcely ranks above them in organization ; its pow- ers of motion being merely such as to enable it to rise and sink in the water. 51. It consists of a large air-bladder, of perhaps a quart in capacity, which floats on the surface of the ocean, and which serves it as a sail. Below this there is a bundle of tentacula, with a mouth and stomach, the whole ap- pearing more like an inorganic mass than a living crea- ture, Fig. 16. These animals are Fig. 16. very abundant in most parts of the Atlantic ocean, where they appear at a little distance like so many large soap bubbles floating along before the wind, only that they pre- sent the most vivid hues of color. " Nothing, it is said, can exceed the beauty of the spectacle pre- sented by a numerous fleet of these animals quietly sailing on the smooth surface of a tropical sea. Whenever the surface is ruffled by the slightest wind, they suddenly INFUSORIA. 25 absorb the air from their viscicles, and thus, becoming spe- cifically heavier than the water, immediately disappear by sinking into the depths of the ocean. By what process they effect the absorption and reproduction of the air in their bubbles, yet remains to be discovered." 52. Echinus.— The shell or skeleton of this animal is well known under the name of sea-urchin, or sea-egg, and is represented by Fig. 17. Its form is spheroidal, resembling that of an orange. On the out- side there are a great number of tubercles arranged in double lines in beautiful symmetry, from the mouth downward, and forming meridian lines from one pole of the sphere to the other. All of these are little balls, smooth, and polish- ed on the outside, and which serve for the articulation of the basis of the spine, with which, when alive, this animal is covered. When examined by a magnifier, it will be seen that the end of the spine- has a socket exactly fitting this ball, thus forming the ball and socket joint, which has a universal motion. The head of the spine is furnished with a capsular ligament to keep it in place, and around which are sets of radiating muscular fibres, by which motion in all directions is given it. 53. The shell is constructed of calcareous matter, and is composed of oblong six-sided plates, accurately fitting each other, and arranged in rows like a mosaic pave- ment, as seen by Fig. 18. There is ion by which the globular shell of the echinus is enlarged according to the wants of the internal ani- mal, for some species grow from the size of a pin's head, to six or eight inches in diameter. This is accomplished by dividing the shell into a great number of six-sided wonderful provis- Fig. 18. Fig. 19. How are the spines of the echinus fitted to its shell? What motion have these spines ? In what manner is the house of the echinus enlarged ? 3 26 MECHANICAL FUNCTIONS. pieces, as seen by the preceding figure, and of allowing constant additions to be made to the margins of these pieces. In this manner it is obvious that the whole struc- ture would be enlarged without changing the shape. Fig. 19 shows the appearance of these plates when magnified. 54. By employing his spines as feet, or levers, this animal is capable of making considerable progress along the bot- tom of the sea. MOLLUSCA. 55. The mollusca, as the name signifies, are animals with soft bodies. They have neither bones, nor hard parts corresponding to the bones of the higher orders of animals. This order includes all those animals which live in calcare- ous habitations, constructed by themselves, and so far as they are popularly known, are called shellfish, as the oyster, muscle, and clam. 56. The shells of the mollusca are formed either of one or of several pieces, which are called valves. Those of one piece are called univalves, those consisting of two pieces are termed bivalves, and those of more than two pieces are multivalves. 57. This order presents a vast number, and variety of individuals, many of which have been minutely examined, and arranged into species, genera, and orders, forming a distinct object of study, entitled the science of CON- CHOLOGY. It is proper, however, to state, that this sci- ence is not founded on the physiology of the animals which inhabit these shells, but on the forms and pecu- liarities of the shells themselves. This arose, originally, from the necessity of the case, for in a great many in- stances the shell is readily obtained, being cast upon the seashore, empty, while the animal which inhabited it is never seen, because while alive it lived only in the un- fathomable depths of the ocean. But could the classi- fication have been founded on the animal organization, it is obvious that this method would be practicable only to a few, since the animals could not be preserved foi What docs the term mollusca signify? What are mollnscus animals? A(.T.IJHAI.A. 27 any length of time. Besides, it being the object of the conchologist to collect, arrange, and preserve some of the greatest beauties which nature has presented to us, in the form of shells, this object could be effected only by an arrangement founded on the shells themselves. 58. Without going farther into the general subject of this order, we shall examine a few individuals as types of their general organization, so far as this is known. ACEPHALA. 59. This term means without head, and common ex- amples exist iii the muscle, oyster, and scollop. These are "bivalve shells, the two valves being united at the back by a hinge, and connected by teeth which lock into each other. Beside these, the two shells are connected by Fisr. 20. means of a strong ligament in form of a short pillar, a 6, represented in Fig. 20, which are the two valves of a spe- cies of unio, or fresh-water clam. These ligaments are very distinct in the common species of venus, called round clam,, seen in all the fish -markets of the Atlantic states. These ligaments hold the two valves together with great force, so that when the animal is alive it is difficult to separate them without a knife. 60. There is, also, in all bivalve shells, a cartilage, gen- erally of a dark color, situated between the two valves at the hinge, the office of which is to force them asunder. 28 MECHANICAL FUNCTIONS. 61. Now as the nourishment of the animal requires that the shell should be kept open to a small distance for the admission of the water, and as its safety might require it to be closed suddenly, provision is made for this action, by a strong muscle passing from one of the valves to the other, and by which they are instantly brought together at the will of the animal. 62. Thus we see that the Creator has furnished these animals with every comfort and convenience which it would be possible fo/ them to enjoy in the situation in which they are placed. A pair of hard shells to protect them — a cartilage, answering as a spring to keep these shells a little 'open, to admit the water from wrhich they obtain food and air — a ligament, to prevent the shells from opening too widely, in which case the sand and mud would destroy the animal — and a muscle, by which he can in an instant close his doors, and become proof against the attack of the most voracious monsters of the deep. When the animal dies, the muscular force ceases, but the cartilage retains for some time its elasticity, and the ligament continues its adhesion to the valves, and from these circumstances it is that we find the shells cast upon the shore, only open to a certain distance, until after the destruction of the ligament, when the cartilage throws them quite open. 63. Several of the bivalve mollusca have the power of giving themselves a considerable motion, by suddenly clo- sing their shells, and thus forcibly expelling the water from between them. The reaction of the fluid on the temporary current thus produced, may often be seen to throw the shell many inches in the opposite direction. 64. The common scollop contrives to give itself motion, even on the shore, by suddenly and forcibly closing its valves ; one of which striking against some impediment, as a pebble, acts as a spring, and thus throws it to a little distance. It is said that when left by the tide, they often reach the water in this way. In bivalve shells, when the animal is alive how are the shells kept open ? What prevents them from opening too widely? How are the shells sud- denly brought together? Why are bivalve shells generally found only partly open on the shore? In what manner do some of these animals give themselves a sudden motion in the water ? How is it said the scollop contrives to move on the shore ? ACEPHALA. 2& 65. The Cardium. — Other bivalves are furnished with an instrument shaped somewhat like a foot and leg, with which Fig. 21. they give themselves a slow, but continued motion through the sand. The form of this in- strument in the cardium or code, is shown by Fig. 21. This organ is a hard mass of muscular fibres, woven together in a very complex manner, and capable of motion in every di- rection. By retracting, and then forcing this instrument forward, a contrary motion is given the shell, for the same reason that a boatman in shallow water, pushes his craft along with an oar from the stern. With his foot, the cardium also contrives to bury himself to any depth he chooses in the sand or mud. For this purpose the leg is elongated, and by a sort of vermicular motion is forced deep into the sand ; then turning up the toe, and forming it into a kind of hook, the animal by an alternate retraction and elongation of the leg, raises and depresses the shell, and by the resistance of the sand on the hook . gradually draws the whole downward. By a reverse of this motion, that is, by first drawing up the foot, and then pushing it downward against the sand, the shell is again forced toward the surface. In this manner does the car- dium bury itself in the sand, in the course of a minute or two, to avoid danger, and as quickly emerges from its hiding-place when the danger is past. 66. With an instrument similar to that belonging to the cardium, many species of bivalve mollusca move along on the sandy bottoms of the water in which they live, with greater or less facility. In nearly every still pond or river, the furrows left by the passage of unios, or fresh-water clams, may be seen running in every direction, and made in this manner. In what manner does the cardium move? How does the cardium burr tself in the sand ? 3* 30 MECHANICAL FUNCTIONS. CEPHALOPODA. 67. Among the mollusca, next to the acephala, in the order of organic development, come the cephalopoda* a name which signifies head-footed, in allusion to the situa- tion of the organs of locomotion, which are on the head. 68. These parts consist of many long, flexible, muscular legs, or fleshy processes, situated like the tentacula of the polypi, around the opening of the mouth. These members answer the double purposes of legs and arms, of feet and hands, for they are not only employed as organs of loco- motion, but as those of prehension also. 69. The Cuttle Fish. — One of these most singular ani- mals is represented by Fig. 22, being one of the sepia, or cuttle-fish tribe, called loligo, or calamary. Fig. 22. 70. In addition to the prehensile powers of these ten- tacula, by which they grasp objects with greater force, by twining around them, they also have the power of adhe- sion by means of suckers, in the form of tubercles placed along their inner sides, as shown in the figure. 71. "So great is the force," says Dr. Roget, " with which the tentacular of the cuttle-fish adhere to bodies by means of this apparatus, that while their muscular fibres continue contracted, it is easier to tear away the substance of the limb, than to release it from its attachments. Even in the dead animal," he continues, " I have found that the suckers retain considerable power of adhesion to any smooth surface to which they may be applied." What is the meaning of the term cephalopoda? Why is this term ap- i«d to wrtain animals? Gue some description of the cuttle-fish. CRUSTACEA. 31 72. Beside the tentacula, the cuttle-fish is furnished with a pair of arms, with the ends expanded, .and also fur- nished with suckers. These long members are employ- ed as cables, and the suckers as anchors, by which these animals fix themselves firmly to/ rocks during violent agitations of the sea, and without which they would un- doubtedly sometimes be dashed to death against the rocky shores. These long arms are not employed by the animal in swimming, the short ones being used as oars for the purpose of impelling this singular creature, not forward but backward, for in this manner do all the cuttle-fish tribe swim. Some of them are fifteen or twenty feet long. ARTICULATA. 73. The animals now to be noticed are articulated, or are provided with joints, by means of which their hard and inflexible parts become the instruments of motion. Hence this division includes animals having joints, wheth- er large or small, and by which they are at once distin- guished from the mollusca, where nothing analogous to articulation exists. This division contains a vast assem- blage of living beings, including the insects, fishes, and quadrupeds. The limits of this work will, however, allow*an account of the physiology "of only a few of the most curious and important. CRUSTACEA. 74. The Crustacea are animals encased in a compact, crusty frame work, composed chiefly of carbonate of lime, as the lobster and crab. 75. The joints of crust aceous • animals are constructed in the most admirable manner, by which in most cases every part of the limb can be moved in all directions They have either three or four pairs of legs, each of which is divided into five pieces, by as many joints. On each side of the head there are long, and often very Why are certain animals denominated articulata? What races of inimals are articulated ? What are the Crustacea ? What parts of ;hese animals are called antennae ? 32 MECHANICAL FUNCTIONS. delicately-formed instruments, called antenna, or feelers. These, in the lobster, are many inches in length, and composed of a great number of rings, articulated to each other in a most beautiful manner, and furnished with minute muscles on the inside, so as to give them motions in all possible directions, at the will of the ani- mal. Some naturalists have supposed that these are not merely the organs of feeling, but that they might also serve for that of hearing, or smelling also. 76. As the coverings of the Crustacea are composed of hard unyielding substances, it is obvious that the animal within must be restrained in its growth, unless some means were provided by which it could relieve itself from such confinement, and accordingly, as nature every- where provides for the comfort and perpetuity of the lowest, as well as the highest of her works, so in the case before us, the animal has the power of casting off its old covering when it becomes too small, the same being soon after replaced by a new one, of ample dimen- sions. 77. The Process of casting the Shell. — These animals cast their shells once a year ; and the manner in which the Lobster, as an example, draws himself out of his old case, his condition afterward, and the incipient forma- tion of the new shell, has been particularly investigated by the celebrated Reaumur. 78. The lobster, some time before the process begins, becomes exceedingly restless, undoubtedly from the pain excited by the pressure of its shell, and thus the poor 'animal is under the necessity of making violent efforts to relieve itself. By this means the shell is burst open along the chest, between the insertion of the legs. The clawrs are the first parts withdrawn from th'eir sheaths, and next the feet, both of which seem to require much muscular exertion ; the head next throws off its case, together with the many-jointed antenna?, and the two eyes are disengaged from their horny pedicles. In this operation, not only the complex apparatus of the What provision has nature made for the growth of the Crustacea? In what manner does the lobster cast off its crusty covering ? CRUSTACEA. 33 jaws, but even the horny cuticle and teeth of the stomach, are all cast off along with the shell ; and last of all the tail is extricated. The whole process is not accomplished without long-continued, violent, and painful efforts. Some- times the legs are lacerated, or even torn off in attempting to withdraw them from the shell, and not unfrequently in the younger animal, death follows before, or soon after its accomplishment. Even under the most favorable circum- stances, the denuded animal is left in the most languid and helpless condition, the limbs being so soft and pliant, as by the utmost exertion to be scarcely able to draw the body along. 79. The flesh is not, however, left entirely without de- fence, for before the old shell is cast away, preparations have commenced for a new one; the membrane sur- rounding the entire animal, and which by the addition of new matter becomes the future shell, having already acquired some density. As soon as the old shell is cast off, this membrane which wras flabby and wrinkled, be- comes tense by the expansion, or sudden growth of the animal, so that the new shell is much larger than the old one. The process of hardening, and thickening, now pro- ceeds rapidly, and the animal soon acquires the perfect use of its limbs, with the addition of about one fifth of its for- mer weight. 80. The lobster, like some species of polypi, already de- scribed, when it happens to lose a limb, soon acquires a new one in its place. Possibly the instinct of the animal has taught it this fact, for when caught by one of the claws, it will sometimes by a sudden jerk break the limb off at the first joint, or at its junction with the trunk, at which place it appears that the new limb grows with the greatest facility. 81. With respect to the growth of the new claw, Reau- mur observed that the wound left by the old one soon becomes covered with a delicate white membrane, with a convex surface. This is gradually pushed forward, be- coming thinner as it is stretched, until it gives way, and exposes the little new claw in the soft state. The new part now enlarges rapidly, and in a few days, acquires a shell as hard as the old one. It however does not attain 34 MECHANICAL FUNCTIONS. the size of the preceding claw, or its mate, and this is the reason why we often see both lobsters and crabs with one of these parts much smaller than the other. INSECTS. 82. This division of animals derives its name from the Latin insecto, which signifies " to cut " because most of them appear nearly divided by an incision through the middle. 83. The natural history of this class of animals affords a highly interesting, useful, and curious field of inquiry. It is a subject, in which it appears to us, the most incuri- ous can hardly avoid to take more or less interest, since its objects are so common and so diversified in appearance, as to have forced themselves, more or less, on the notice of every one who has his perfect senses. 84. Insects have organs of locomotion, sensation, sight, and taste, and many of them are endowed with the most wonderful instincts ; but they have neither heart, arteries, nor lungs, though some of them have parts analogous to the two latter organs. 85. Changes in the forms of Insects. — Most insects be- gin their lives in the form of larva?, or worms, the power of flight being reserved until after having passed through several preparatory changes, they attain their perfect state. These changes are termed metamorphoses, and are most conveniently seen in the lepidopterous, or butterfly tribes. 86. Beginning with the hatching of the egg, laid by the butterfly, the following changes take place, before a butterfly is again produced. Most of these eggs are no larger than mustard-seeds, and are attached to the leaves of plants on which the future larva, or caterpillar, is to feed. In this the butterfly is directed by that most mysterious property called instinct, and by which she never fails to place her eggs on such plants as are the most proper food for her future progeny. Thus somt What is said of the lobster acquiring a new claw in place of one de stroyed? Whence is the term insect derived? What organs have insects . In what form do insects begin their lives ? INSECTS. 36 species place their eggs on nettles, others on the parsnip, others on the cabbage, &c., and it is found that if the cater- pillars produced, are transferred from one of these plants to the other, they in most cases die of starvation, or im- proper food, being unable to partake of any other, except that on which they are found. 87. The young caterpillar is at first exceedingly small, being often less than a line in length. As they enlarge in size, their skins being at first somewhat elastic, are stretched so as to accommodate their growth. But this part growing more firm with age, finally refuses to yield any further to the growth of the animal. It is then cast off in the following manner. The worm fastens the old skin to the side of a leaf, and then breaks through that part which covers the head, and liberating its fore feet, gradually draws the body out, the skin remaining sta- tionary. But before this is done, a new skin has been prepared underneath, more capacious than the former, and which again for a time allows the insect to grow. This, however, in its turn becomes too small ; or rather the caterpillar becomes again too large for its skin, and the same process is repeated four or five times before the full size is attained. 88. When the larva is full grown, and therefore when there is no further necessity for a new skin, it makes a much more decided and important change than those it "had before undergone ; for although it had thrown off coat after coat, it still had become nothing more than a worm. But now it not only strips itself of the cater- pillar's skin for the last time, but so changes its form as to have no appearance of what it was before. It is wrapped in a shroud of skin, presenting no vestige of its former legs, mouth, or any other member. It is fixed in its place by a rope of silk, or wound up in a cocoon of the same material, and presents in either case, scarcely any signs of life. In this condition it is said to be in its pupa, or chrysalis state. What is said of the different plants on which the butterfly lays her eggs ? What change takes place when the larva passes to the chry sails ? 36 MECHANICAL FUNCTIONS. Fig. 25. Some insects 89. The silk worm. — Of the silk worm, Fig. 24 repre- sents the full- Fig. 24. grown caterpil- lar, and figure 25 the chrysalis which it produ- ces, the latter be- ing deprived of its cocoon in order to show its form and size. 90. The chrysalis remains in this state for various lengths of time, depending on the species to which it belongs, or on the warmth to which it is exposed. continue in this state for years, while others emerge and become perfect in a week or two. During this time, the organs which are to serve them in their future and more elevated career, are preparing ; although very little change can be observed in the size, or appearance of the chrysalis. 91. When the time arrives that these several organs are completely formed, and the butterfly is ready to assume its rank among the beautiful and lively inhabitants of the air, then it is that the insect bursts the shroud in which it has so long been enclosed, and comes forth in form and colors so beautiful, and in spirits so joyous and sportive, as amply to Fig. 26. compensate for its in- glorious and degraded origin. Our insect has now arrived to its imago, perfect, or butterfly state, the moth, of the silk- worm being represented by Fig. 26. 92. Through these several changes do all the butterflies, and a great proportion of the insects, properly so called, pass. Some of them enjoy their perfect state only for a short time, a few hours; while others continue to dis- play thek beauties, and wanton among the sweets of the How long do insects remain in the chrysalis state ? METAMORPHOSES OF INSECTS. 37 garden for weeks and months. In all cases they deposite eggs for a future race before their final exit. 93. The moth, or as it is more commonly called the butterfly, or the silk-worm, has, like all other insects, six legs. The wings are four, of a grayish white color, with two transverse undulated bands across them. They are far from being beautiful when compared with most others of the same race, and are also entirely void of that sport- ive vivacity, so common to most other species. i METAMORPHOSES OF INSECTS. 94. The subject of insect metamorphoses has excited curiosity, and has been the object of inquiry and inves- tigation among naturalists and philosophers in all ages of the world. Having given a detail of the changes which take place during this process in a single species, we are now prepared to pursue this wonderful subject more at large, and to show the variety and difference of circumstances which attend the same changes in other species. 95. Messrs. Kirby and Spence, in one of the best works ever written on insects, introduce the subject of their metamorphoses in the following manner : " Were a naturalist to announce to the world the discovery of an animal, which, for the first five years of its life, existed in the form of a serpent, which then, penetrating into the earth, and weaving a shroud of pure silk of the finest texture, contracted itself within this covering into a body without external mouth or limbs, and resembling more than anything else an Egyptian mummy ; and which, lastly, after remaining in this state, without food, and without motion, for three years longer, should, at the end of that period, burst its silken cerements, strug- gle through its earthy covering, and start into day a winged bird — what, think you, would be the sensation excited by this intelligence 1 After the first doubts of its truth were dispelled, what astonishment- would suc- ceed ! Among the learned what surmises, what inves- What is said of the time which the chrysalids of insects remain in the torpid state ? 3$ MECHANICAL FUNCTIONS. tigations ! Among the vulgar what eager curiosity, what amazement !" 96. In the same spirit, Swammerdam, who spent most of his life in making observations on insects, observes on the same subject : " This history is so extraordinary, so amazing in all its circumstances, that it might very well pass lor a romance, were it not built upon the most firm foundations of truth." 97. With respect to the size and appearance of the cat- erpillars, and of the chrysalids they form, as well as the situations in which they are placed, and the time of re- maining in the torpid state, there are nearly as many varieties as there are species of insects. Some larva:- descend deep into the ground before they assume the torpid state, and there remain three or four years before they acquire wings. Others weave small cocoons, and having thus covered themselves in beds of silk, then change to chrysalids. These are sometimes constructed in the earth, and sometimes attached to the sides of fences, or the side of any vessel in which the worm is confined. If confined in a glass vessel, the observer may witness the whole process of weaving the cocoon, and of casting off the old skin, by which the chrysalis becomes apparent. 98. The positions in which the larvee place themselves in order to undergo this change, are also extremely vari- ous. One species suspends itself to a leaf with its head downward, being only fixed by the tail ; another passes a rope of silk around its neck, and thus hangs in an ob- lique position ; while others are simply glued in a hori- zontal position, in any convenient place. 99. Larva which feed on the Parsnip. — There is a common larva which may be seen feeding on the leaves of parsnips in the autumn, and which every one has noticed on account of its handsome appearance, and the foetid odor which it emits on being disturbed. The color is greenish yellow, with bands of velvety black, and when full grown it is nearly two inches long. The youngei ones of this caterpillar wrould at first be taken for a diffei What is said of the positions in which chrysalids are placed ? METAMORPHOSES OF INSECTS. tfi* ent species, being dotted, or sprinkled, with yellow and black, instead of having the colors well defined. If the young naturalist will take a sprig of the parsley with one of these on it, and put the whole into a glass jar, or other place of confinement, taking care to water the plant, he will soon find it to be identical with the large ones. 100. This larva is remarkable for having on the back of the neck, an instrument composed of two fleshy horns, branching from a common stem somewhat like the letter Y. This organ appears to be similar in some respects to the horns of snails, and is capable of similar movements, being completely retractile. When the animal is irritated these horns are projected, and it appears from the observa- tion of Reaumur, that this organ secretes an acid liquor, which emits the unpleasant smell, and which every one who has touched one of these worms, cannot but have perceived. Reaumur supposes that this acid is a means of defence against the attacks of the ichneumon, a small fly which deposites its eggs in the flesh of the larvae of various insects. 101. This larva, when spinning the silken cord by which it is to be supported in the F'S- 27. Fig. 28. chrysalis state, invariably fixes it round the neck at the junction of the fifth and sixth segments, where there is a cavity in which it is kept from sliding backward or forward. This cord ap- pears to pass under the skin of the chrysalis, but on ex- amination with a magnifier, it will be seen, only almost concealed in a deep chan- nel. The larva and its chrysalis, both of the natur- al size, are represented by Figs. 27 and 28 j the latter be- ing suspended by the cord in the manner described. 102. Difference in the chrysalids of butterflies and moths. — There are differences between the chrysalids of 40 MECHANICAL FUNCTIONS butterflies and moths, and also between these species of in- sects, which it is proper to point out at this place. The chrysalids of butterflies are naked, that is ^ Fig. 29. they are not covered with cocoons, but are attached to trees, or other substances, by silken cords, passing round the neck (Fig. 28), or are attached by the tip, and hang suspended as represented by Fig. 29. They are also angular. The antennae of butterflies are club-shaped, that is, they are thickest toward the tip, or end in a bulb, as seen by Fig. 30. Fig- 30. 103. The chrysalids of the moths, or millers, as they are sometimes called, are commonly short cones com- posed of several rings, and presenting no an- pjg. 31. gles. They are usually enclosed in brown silk cocoons, sometimes glued to the sides of trees, or fences, and sometimes buried in the ground. A few are naked, and are suspended by the small end. Fig. 31 represents the most common form. Both forms of chrysa- lids are occasionally dotted with spots exactly resembling gold. What difference is there between the chrysalis of a butterfly and a moth? What is the difference between the antennae of these insects ? METAMORPHOSES OF INSECTS. 41 104. The antennae of moths are somewhat sword- shaped, tapering from Fig. 32. the insertion to the point, and are sometimes frin- ged,Fig32. 105. The butterflies are diurnal insects, fly- ing only in the day. The moths are nocturnal., sel- dom flying except at night, or after sunset. Some of the small species are, however, occasionally seen by day. 106. Some of this tribe called hawk-moths, have a pro- boscis or tongue, several inches long, by means of which they pump -the honey from the nectaries of flowers. Both butterflies and moths, are furnished with four wings, six legs, a proboscis, and suck honey as their chief aliment. 107. Change from the chrysalis to the butterfly. — Swammardam, one of the oldest and best authorities on the anatomy of larvaB, demonstrated that even before the time when the caterpillar changes into the chrysalis, all the parts of a butterfly may be discovered within its skin. His directions for observing this phenomenon are, to take a full-grown caterpillar^, and having tied it to a thread, put it into boiling water, and take it out soon after ; thus its external skin will separate, and may be easily drawn off from the butterfly, which is contained folded up in it. This done, it is clearly and distinctly seen, that within this skin of the caterpillar, a perfect and real butterfly was hidden. 108. On examining certain chrysalids, which are cover- ed with a light-colored shroud, and consequently translu- cent, we are able to discover the eyes of the butterfly, as well as its wings, which are of small size, and folded upon the sides. There may also be observed several slender, ribs or divisions, arising from the head, and which, on more What is the difference in their time of flying ? What is said of the exist- ence of the butterfly within the skin of the larva ? What is said of the but- terfly in the chrysalis ? •MECHANICAL FUNCTIONS. minute examination, may be seen to consist of the two fila- ments of the tongue, or proboscis, the legs, and the antennae of the butterfly. 109. It appears, therefore, that during the chrysalis state, the future organs which the butterfly requires, are in the progress of perfection, as those of the chicken aie in the egg, and that when the insect has remained under this form a sufficient length of time for these parts to gain a proper degree of consistence and strength, it then bursts open the membrane, and makes its escape, as the young quail does from its egg-shell. 110. Just before the butterfly emerges from its confine- ment, it is easy to see, in some chrysalids, the form of the legs, antenna, and tongue, and even the color of the wings. The extremities of the legs may be seen to move, the wings to enlarge, and finally the whole insect to struggle as if determined no longer to submit to con- finement. After a few such efforts, the membrane of the chrysalis gives way in a longitudinal rent down the back, wrhere a suture may be observed, undoubtedly for this purpose. The rent then extends over the head, and down the breast, and after various efforts and contor- tions, the butterfly finally disengages itself entirely from its covering, leaving it divided into several sections, as represented by Fig. 33. But the insect, Fl£- 33- though now disengaged from its prison, has not yet attained its full perfection, for, beside being exceedingly weak, so as hardly to be able to crawl, its wings are folded and doubled together in such a manner as to make them appear like pieces of wet paper, as shown by Fig. 34. The spots and markings are also indis- tinct, as though their wet condition had made the colors run into each other. But they expand with such rapidity, that, ac- cording to Swammardam, " the naked eye cannot trace their unfolding, for, from reaching scarce half the length of the body, they acquire, O miracle of mir- acles ! in the short space of about half a quarter of an hour, their full extent, and METAMORPHOSES OF INSECTS. 43 bigness." The colorings peculiar to each species also be- come defined and perfect as the wings expand. 111. The means employed to effect a change so wonder- ful with respect to the wings, and in so short a time, has not been left unexplained. 112. The wings of the young butterfly, how expanded. The wings of butterflies are composed of two fine mem- branes between which are little veins or ribs resembling those of the leaves of some plants. These may be seen by the naked eye, when the scales, or dust which colors the wings is rubbed off, and are called nervures. They are hollow tubes, having a communication at the insertion of the wing with the body of the insect. Into these, the young butterfly forces a quantity of air, and perhaps also a fluid, and by the distention of which, the folds and wrinkles of the soft and wet wings are in a few moments oblitera- ted. The nervures, and also the fully-developed wings, are shown by Fig. 35. Fig. 35. 113. These when compared with Fig. 34, will show the change produced by the means above described in " half a quarter of an hour," and at the sight of which, Swammar- dam could not help exclaiming, " O ! miracle of miracles !" The whole process, indeed, from the hatching of the egg, to the perfection of the butterfly, though not a miracle, because the whole is in the ordinary course of nature, must ever be considered among the most wonderful se- In what manner does the butterfly make its escape from the chrysalis ? Is the insect perfect when thus disengaged ? In what manner are the new wings of the butterfly unfolded and distended ? 44 MECHANICAL FUNCTIONS. ries of natural phenomena which man has been allowed to witness. Who can study such traits of nature, with- out acknowledging the care, design, and wisdom of the Creator to be displayed in them in a most striking and wonderful degree ! 114. Wing-scales of butterflies. — The soft down which covers the wings of butterflies and moths, W7hich ap- pears like the finest dust, and by which all the splendid variety of colors are given to these insects, is found when magnified, to consist of scales, or feathers, of different, but regular forms. It is from these scales that the name of this genus, lepidoptera " scaly-winged," is given. 115. According to some naturalists, these minute parts should be considered rather as feathers than as scales, since they are affixed to the wings by minute quills. But others consider them as scales, from their being composed of merely membranous plates, having nothing in common with feathers, excepting, perhaps, the manner in which they are attached. The reader may have the Fig. 36. opportunity of deciding this matter for himself, by con- sulting Fig. 36, where the forms of a number of these parts are shown, highly magnified. The number of these on the wings of the larger butterflies, must amount METAMORPHOSES OF INSECTS 45 to millions, since Leuwerihoeck, the best observer on such subjects, found more than 400,000 of them on the wings of the silk-worm moth, which is comparatively a small insect. 116. The construction and arrangement of the parts of these scales are very regular and beautiful, their surfa- ces being striated with parallel, and equi-distant lines, the distinct visibility of which, in those from the Pontia brassica, or cabbage-butterfly, is considered as affording an excellent test of the goodness of microscopes. 117. The forms of these scales as seen by the adjoining figures are exceedingly various, as also their sizes, when magnified by the same power. These differences of form occur not only in the different species, but also on different parts of the wings and body of the same in- sect ; for the surface of the body generally, as well as the legs, and in some species the antennaB, are more or less covered with these scales. These forms are indeed so various on different parts of the same insect, that in the works of that distinguished naturalist, Lyonet, there are six quarto plates nearly covered with the delineations of different forms of these scales found on a moth of the silk-worm tribe, the Bombyx cossus. 118. The arrangement of these scales upon the wings are in regular transverse lines, the ends of one row lying over the basis of the next, like the shingles on the roof of a house. When these are removed from both sides of the wings of a butterfly, it will be seen that these parts are exceedingly thin and transparent, like the wings of the dragon fly and bee. 119. Red drops emitted by Butterflies. — Several spe- cies of butterflies, just after the time of changing from the chrysalis to the perfect state, or perhaps at that of emer- ging from their place of confinement, emit several drops of a red fluid, resembling blood in appearance. When a great number of these insects have been produced at Whence does the genus to which the butterfly belongs derive its name? What is said with respect to down on the wings being feathers? What is said of these scales with respect to their being a test of the goodness of microscopes? What is said of the different forms of these scales? How are they arranged on the wings of the insect ? 46 MECHANICAL FUNCTIONS. the same time and place, as sometimes happens, the people have been struck with terror and dismay, taking these drops for the effects of a shower of blood, which of course could portend nothing less than some direful calamity to the country. The author of this volume, last October, obtained a specimen of these bloody drops, from the Papilio artica, the caterpillar of which was taken from the common nettle, and underwent the met- amorphoses in confinement. The red drops happening to fall on a piece of oil-cloth carpet, were cut out and preserved. They are of a deep red, and do not fade by keeping. In consequence of this circumstance, the au- thor's attention was excited to the subject, and he threw together the following remarks and facts, which were offered as a little contribution to " The Hartford Natural History Society." 120. Ancient showers of blood explained by facts, in the Natural History of the Butterfly. — It is well "known to the general reader, that various authors have described showrers of blood as falling from the heavens, and that such phenomena have been considered the miraculous precursors of some extraordinary, or direful event. Thus Ovid has commemorated such an occurrence among the other prodigies which attended the violent death of the great Roman dictator. " With threatening signs the lowering skies were filled, And sanguine drops from murky clouds distilled." 121. Such occurrences are alluded to by several other ancient writers, both Greek and Roman. Homer speaks of showrers of blood which fell before his time, and also one or two, of which it would appear that he was an eyewitness. Such phenomena he declares in- dicate the direct and violent encroachment of the gods on the established laws of nature. Cicero also alludes to such events, and was the first to doubt their preter- natural origin ; but in his attempts to account for them on natural principles, he involves suppositions not less difficult to explain than the phenomenon itself, even with out reference to its real cause. 122. Dion Cassius, who flourished in the third century, mentions a shower of blood which fell in Egypt in the METAMORPHOSES OF INSECTS. 47 time of Octavian. This, he considers, a very rare and ex- traordinary occurrence, not however, it would seem, be- cause it was of blood, but because, as he states, it fell in a country where showers of any kind are unknown. 123. Stowe, the old British Chronicler, also speaks of several cases of what he calls blood-rain. " In the days of Rivalla," says he, " it rained bloud three days, and then a great mortalitie caused almost desolation." Again, " Li the time of Brithricus of the blood of Cerdicus, who was king of the West Saxons for seventeen years, it rained bloud, which falling on men's clothes, appeared like crosses." Nor does Hollingshed fail to record some scraps of the same history. He relates that in the fifth centuiy, " at Yorke it rained bloud," and that in the seventh, " corne, as it was gathered in the herveste-tirne, appeared bloudie." From Batmans' " Doome " we find that in 1553, it was deemed among the forewarnings of the deaths of Charles and Philip, Dukes of Brunswick, that "ihere w«re drops of bloud upon herbs and trees." 124. In the 'days of Nero, it is said that blood-rain fell in such quantities as to tinge some rivers of a red color. It is likewise recorded by historians, that the phenomenon, or miracle of falling blood, either seen on the leaves of plants, or on stones, or fences, has occurred at various times and places, ever since the Christian era. But after having quoted the above authorities, it will be needless to specify others to establish the general fact of such records. It will therefore be sufficient to state that two instances of bloody rain are recorded to have fallen in the tenth centu- ry, one in the eleventh ; two in the twelfth, one in the thirteenth ; two in the fourteenth ; one in the fifteenth ; and five in the sixteenth. 125. Thus, although it appears that almost from the earliest times of history, it has been understood and be- lieved that showers of blood actually falling from the air, were not uncommon, still no one as we shall see directly, until about the beginning of the seventeenth century, un- dertook any serious investigations for the purpose of ac- counting for phenomena so extraordinary. 126. It is most probable this neglect of inquiry aros* from a superstitious dread of interfering with so sacred a 48 MECHANICAL FUNCTIONS. subject ; for it was generally believed that such showers undoubtedly prognosticated some direful event, and hence, they were received as miraculous warnings, or special interpositions of Providence, in the affairs of men. Under such a belief, we can hardly* wonder that few or none u could be found, who wrere so bold, or perhaps wicked, as to attempt to account for such occurrences on natural principles. Such conduct would have been a virtual denial of the miracle itself, or at least a fool-hardy at- tempt to explain the acknowledged special communica- tions of heaven by a reference to the ordinary laws of nature. 127. It is true that in the time of Hippocrates, a learned doctor named Garceus, declared it as his opinion, that blood-rain was common rain boiled by the heat of the sun, but with this exception, we find no expressions of doubt with respect to the miracle, or at least no attempt to solve the mystery, from the time of Cicero to that of the cele- brated naturalist Reaumur, in the beginning of the seven- teenth century. 128. Before we proceed to the explanation, it may be proper to remark, that so far as we know, all the ancient accounts of bloody-rain, fail entirely with respect to the detail of attending circumstances. We are not informed whether such showers fell from thick clouds, accompanied with lightning and thunder. Whether they fell by night or by day, or indeed whether the red drops were ever seen to descend, or whether they were first discovered on the leaves of plants, and on stones and fences. Hence we may fairly conclude that the fall of bloody showers have only been inferred from appearances on, or near the ground. 129. It is now known that there are several species of butterfly which emit red drops, immediately after their emergence from the chrysalis, as the papilio io, or the pea- cock butterfly ; the papilio urtica?, and several others. 130. The report of Reaumur, to which we have before alluded, and which accounts satisfactorily for these bloody showers, is as follows : In the beginning of July, 1608, the people of Aix la Chapelle, were in the utmost alarm from what they thought a shower of blood, that had fallen in the suburbs, and some miles around the place. METAMORPHOSES OF INSECTS. 49 M. de Peiresc, a philosopher, who, among other kinds ol* knowledge, had not neglected that of the operations and economy of insects, was consulted on the subject. He found the walls of a church-yard near the place, and the walls of several small villages in the neighborhood to be spotted with large drops of a blood-colored liquid. A little before this time this gentleman had happened to pick up a large and beautiful chrysalis, which he had carefully laid in a box. Immediately after its transformation into the butterfly state, he remarked that it had left a large drop of a blood-colored liquid in the bottom of the box. The red stains on the walls, and the stones near the highways, and on the leaves of plants in the fields, were found to be perfectly similar to that left on the bottom of the box. M. de Peiresc hesitated no longer to pronounce that all the blood-colored stains wherever they appeared, proceeded from the same cause. The prodigious number of butterflies which he at the same time saw flying in the air, confirmed his original idea. He likewise observed that the drops of miraculous rain were never found in the middle of the town, but that they appeared only in places bordering upon the country ; and that they never fell upon the tops of houses, or upon walls more elevated than the height to which butterflies generally rise. What the investigator of these facts saw himself, he showed to many persons of knowledge, or curiosity, and finally established as an incontestable fact, that the pretended drops of blood were in reality nothing more than drops of red liquid deposited by these butterflies. It is also de- serving of remark, that all the showers of blood that have been recorded to have happened, took place in the warm season of the year, when butterflies are most nu- merous. 131. And now who will deny the practical use of en- tomology, when these simple facts have been the means of delivering the world from the thraldom of superstitious fear, which from time immemorial, has been consequent upon the belief in miraculous showers of blood. When Newton demonstrated that the comets, instead of wan- dering in any direction aud without order, were confined to regular orbits, and therefore that we of the earth, had 5 50 MECHANICAL FUNCTIONS. nothing to fear from them, astronomy was hailed as the noolest and most useful of sciences on this very account ; and yet astronomy in that instance did nothing more for the world than entomology has done in the case be- fore us. 132. Tusseh Silk-Worm. — Before we leave the lepi- dopterous insects, we will describe a species of silk worm found in India, which, although it is not domesticated like the common one of Europe and America, the bombyx mori, still appears from time immemorial to have furnish- ed the natives with an abundance of an inferior kind of silk for common uses. It is called the Tusseh silk-worm, and is found in abundance in many parts of Bengal and the adjoining provinces, and the cocoons are reeled and wove into a coarse, dark-colored, but most durable fabric, called Tusseh dootheis, much worn by the bramins, and other classes of Hindoos. 133. This silk-worm, whether from want of skill, or from the wild habits of the moths, is unknown, has never been reared in the usual manner of other worms ; the na- tives, therefore, every year, at the proper time, go into the jungles and find the young worms on the limbs of certain trees, WThich they cut off and convey to other trees of the same kinds near their habitations. These are known by the native names of asseen and byers trees, and these trees are guarded day and night, in order to prevent birds and bats from destroying the young caterpillars. In two or three weeks, these worms acquire nearly their full size, being monsters of four inches in length, and three in circumference ; their colors are of a light green, with a yellowish stripe on each side, the sixth and seventh rings being marked with an oblong golden spot. From the back issue a few long, coarse, distinct hairs, with others of a smaller size scattered over the body, Fig. 37. 134. When these worms are ready to spin their cocoons in which they change to the chrysalis state, they begin by attaching glutinous filaments to a leaf as a found- ation, and afterward spin a strong cord by which the fu- ture cocoon is suspended to a twig for additional security. The cocoon is of an oval form and firm texture, as rep- BEETLES. 61 resented by Fig. 37, a. The chrysalis remains in the torpid state for nine months, when it discharges from Fig. 37. the mouth a quantity of corrosive liquor, which softens the upper end of the cocoon, and the moth makes its escape. 135. These insects are of enormous size, the largest measuring, with the wings spread, six, or even eight inches across. They are exceedingly vigorous on the wing, and fly to great distances. Tho natives often catch, and mark them and then let them fly ; the marks of the different districts being known, it is said they are frequently caught more than a hundred miles distant from the places where they were marked. 136. The wings of these insects are of a uniform yellow- ish brown, with one round transparent spot in each of the fore wings. They live from six to twelve days, deposite their eggs, and die. BEETLES. 137. The beetles belong to the Lirmsan order coleoptera, which word signifies " wing-sheathed," so called, because these insects are provided with hard wing cases, with which they cover, when at rest, their proper wings. These cases are called elytra, and when shut together, form a longitudinal suture along the back. A great variety To what order of insects do the beetles belong ? What is the mean- ing of the term coleoptera* What are the wing cases of these insects called? 52 MECHANICAL FUNCTIONS. of this tribe are known under the common appellation of bugs. Most of them fly only in the night, and some of the larger make a deep-toned sound with their wings, so loud as to be heard many rods distant. 138. The larvae of some of this tribe, in consequence of their living under the ground, and destroying the roots of plants, which serve them for food, are exceedingly destruc- tive to the farmer. The perfect insects also sometimes make terrible desolation among the forest and other trees. 139. The blind beetle. — The melolontha vulgaris, called, also, chafer, blind beetle, or more commonly cock-chafer, is one of these insects. 140. The larva of this beetle Fi&- 38- is known to farmers under the name of the white worm, and is represented by Fig. 38. The eggs of these worms are deposi- ted in the ground by the parent insect, and when first hatched are of very small size. As they grow, they change their skins several times, and at the end of four years, during which time they remain in the earth, they acquire the size represented, having six legs, armed with strong claws, and a reddish head. During its subterranean residence, it lives on the roots of grass, sometimes committing the most deplorable ravages. When their numbers are great, they cut off all the roots of the grass in the richest mead- ows, leaving the turf entirely detached and dead, so that it may be rolled up by the hands like a carpet, without the aid of a turfing knife. Underneath, the soil appears pulverized, and turned into a soft mould, like the pre- pared bed of a garden. In this, the worms are seen coiled up and lying on their backs, generally almost motionless. 141. Some years since, a poor farmer in Norwich, Eng- land, suffered so much from these worms as to destroy all his hopes, and the authority of that city out of compassion, voted him 25 pounds to assist him under such a calamity. This man and his servant testified, that they had gath- BEETLES. 63 ered eighty bushels of these obnoxious creatures, but still his farm, for the season, was destroyed. 142. At the close of the fourth year, these larvae con- struct for themselves large oval cocoons, having first de- scended to the depth, it is said, sometimes of five or six feet below the surface of the ground. 143. These cocoons are of an oval form, of considerable bulk, and are constructed with a good deal of ingenuity, and reference to comfort, being wove of silk and lined with the same. 144. Fig. 39 shows the section of Fig. 39. one of these cases with the worm in it. The covering of this chrysalis is so thin and transparent that all parts of the insect may be seen through it. In the month of February, the perfect insect rends its envelope, and emerges from it, though still several feet under ground. It is now yellowish, soft, and weak, but gradually acquires strength and firmness, and begins slowly to make its way toward the surface. This, however, it does not reach until May, when it is not un- common to find these yellowish bugs, as they are called, just under the surface, and about which time they as- sume their new and elevated condition as inhabitants of the air. 145. The cockchafer is Fig. 40. a strong insect, of a yel- lowish brown color ; an- tennse largely club-shaped; the feet armed with sharp claws, and the body some- what hairy. Fig. 40 rep- resents this insect of the natural size. 146. During the day these beetles remain motionless sometimes concealing themselves under the bark of trees, and about fences ; but 9n the setting of the sun, they is- sue forth from their hiding-places to feed on the leaves of various 'trees, and sometimes their numbers are sucn as to do as much mischief in their perfect state, as they 5* 54 MECHANICAL FUNCTIONS. did when in that of the larvae, devastating whole forests in such a manner as not to leave a green leaf behind them. 147. Devastations committed by this Beetle. — In the Philosophical Transactions, for the year 1697, there is an account of the appearance of these insects in certain parts of Ireland and the ravages they committed there. " Mul- titudes," says this statement, " appeared among the trees and hedges in the daytime, hanging by the boughs in clusters, like bees when they swarm. In this posture, they continued, with little or no motion, during the heat of the sun ; but toward evening they would all disperse, and fly about with a strange humming noise, like the beating of distant drums, and in such vast num- bers that they darkened the air for the space of two or three square miles. Persons travelling on the roads, or abroad in the fields, found it very uneasy to make their way through them, they would so beat and knock them- selves against their faces in their flight, and with such force as to make the place smart, and leave a mark be- hind them. In a short time after their coming, they had so entirely eaten up and destroyed all the leaves on the trees for some miles around, that the whole country, though in the middle of summer, was left as bare as in the depth of winter ; and the noise they made in gnaw- ing the leaves made a sound resembling the sawing of timber. They also came into the gardens and destroyed the buds, blossoms, and leaves of all the fruit-trees, so that they left them perfectly naked ; nay, many that were more delicate than the rest, lost their sap, as well as leaves, and quite withered away, so that they never re- covered again. 148. Their numerous young, hatched from the eggs which they had lodged under gfound, near the surface, did still more harm in that close retirement, than all the flying swarms of their parents had done abroad ; for this destruc- tive brood, lying under ground,^ite up the roots of corn and grass, and thus consumed the support of both man and beast," Many other instances of similar devastations are recorded to have been committed by these insects in differ- ent parts of the world. MANTIS. 65 MANTIS. 149. There is an hemipterous, or half-winged insect of very singular manners and habits called the orator mantis, and sometimes the praying mantis, from the position in which it is usually found. This insect is of considerable size ; the elytra, or wing-cases are of a bright green color, and on each of the wings there is a black spot. 150. The common posture of the mantis is that of rest- ing on its hind-legs, and erecting its fore-feet, holding them close together, and giving them a quick motion, as if, as some say, it was in the act of praying, Fig. 41. Fig. 41. Hence among certain people, this creature, has been held in great veneration from time immemorial. It has been supposed to tell fortunes, forewarn of evils, and to do many other things, according to the vividness of super- stitious imaginations. Dr. Moufet, who wrote a work in folio, on insects, in the sixteenth century, very seriously tells us of this insect, that " they are called mantes, that is, fortune-tellers, either because by their coming they do show the spring to be at hand, so Anacreon, the poet sang ; or else they foretel death, or famine, as Cselius, the scholiast of Theocritus writes ; or, lastly, because it al- ways holds up its fore-feet like hands praying, as it were, after the manner of their diviners, who, in that gesture, did pour out their supplications to their gods. So divino a creature is this esteemed, that if a child asks the way to such a place, she will stretch out one of her feet, and show 56 MECHANICAL FUNCTIONS. him the right way, and seldom or never misses. As she resembleth these diviners in the elevation of her hands, so also, in likeness of motion, for they do not sport themselves as others do, nor leap, nor play, but walking softly, she returns again modestly, and shows forth a kind of mature gravity." This is only the position of the mantis that it takes to catch its prey. 151. The praying position and soft modesty of this insect, which charity and superstition thus metamorphosed into kindness and virtue, by a more attentive examination of its habits, prove to be nothing more than cunning de- vices to secure its prey, being one of the most cruel and voracious of all the insect tribe. The patience of the mantis, says Bingley, in waiting for its prey, is remarka- ble, and the posture to which superstition has attributed devotion, is no other than the means used to catch it. When it has fixed its eye on an insect, it rarely loses sight of it, though it may cost some hours to accomplish its destruction. If it see an insect a little beyond its reach, over its head, it slowly erects its long thorax, then resting on the posterior legs, it gradually raises the ante- rior also. If this brings it near enough to the insect, it throws open the last joint of its fore-paws, and snaps the object between the spines that are set in rows on the second joint. If it is unsuccessful, the paws are not re- tracted, but still held forth waiting for the victim to come again within its reach. Should the insect go far from the spot, the mantis flies, or crawls after it, slowly, like a cat. 152. Observations of Roesel. — Roesel, the naturalist, desiring to study the character and habits of this curious creature, put some of the eggs into a glass case until they hatched. The young ones immediately displayed the most savage disposition toward each other, but Roesel supplying them with flies, which they tore in pieces and devoured' with avidity, he in this way saved some of his brood for a time. But notwithstanding he supplied them well with insects, they continued to de- vou: each other apparently through wantonness. Des- pairing at last of rearing any of them to the winged state, he separated them into small companies, under MANTIS. 57 different glasses, hoping in this way to render them more pacific. But still the strongest in each little community, with the same savage disposition as before, tore in pieces the weaker. 153. Finally, he put a pair of these insects, full grown, into a glass case, and having taken the precaution of first supplying them with food, watched their actions. But no sooner did they espy each other, than they stood stiff and motionless, each eying the other with an air of the sternest defiance. In this posture did they remain for many minutes, when the whole frame of each became violent agitated ; their necks were elevated, their wings expanded, and in this state they rushed toward each other with the utmost fury, and hewed away with their sharp, sabre-like fore feet, like, says Roesel, a couple of infuriated Hussars. 154. Barrow, the traveller, states that the Chinese keep these insects in separate bamboo canes, for the pur- pose of seeing them fight, as other people do game-cocks ; and that in the summer months, scarcely a boy is seen in the streets, without a cage of these ferocious warriors ; a practice as barbarous with respect to these animals, as it is humiliating to human beings. Fig. 42. 155. Follicle of the Mantis. — The case, or sort of fol- licle which the mantis constructs to contain her eggs is not the least curious thing belong* ing to this famous insect. This case is about two inches long, of a yellow color, of a texture- like parchment, and curiously reticulated, or waved on the out- side. The shape is that of a double cone united at their bases. It is fixed to the stalk of some plant, as seen by Fig. 42. Along one side there is a kind of suture through which the young escape as they are hatched, the figure showing some of them in this act. 58 MECHANICAL FUNCTIONS 156. The eggs are very numerous, and are ananged in rows, as seen by Fig. 43, which is a tranverse section of 42. One of these follicles being sent to Roesel, he observed that a double row of egg-like bodies sprouted up in close contact with each other in a furrow, which divide the egg case longi- tudinally; these little eminences soon became animated, for out of them he perceived the little mantes struggling to escape. As soon as the one has succeeded in freeing itself from the egg, it ran off with the agility of an ant, which it resembled in form and nimbi eness. MUSQUITO. 157. The general appearance and habits of the mus- quito are too well known to need description. It belongs to the order diptera, that is, double-winged, these tribes having only two wings, of which the common house-fly is another example. 158. The gnat and musquito belong to the same spe- cies, the latter being only a large variety of the former. The larvse of these insects in the wa/m season, are common in all stagnant pools and ditches. Even a small vessel of water, if allowed to stand still, will soon exhibit these little beings diving and swimming about in all directions, generally with their head downward. They are, howev- er, obliged often to rise to the surface to breathe, being furnished with a small cylindrical tube for this purpose. 159. Changes of the Musquito in the Water. — The musquito undergoes several metamorphoses before it leaves the water. . The larva, at first, is composed of nine segments, each of which is furnished with a number of fine cilia on both sides, as shown by Fig. 44, which is a magni- fied view of the insect. 160. After having thrice changed its skin, as it increases in size, it appears in a sort of lenticular, or bean-like form, as shown by Fig. 45 In this state it is still capable of moving briskly through the water, in the manner Fig. 44. MUSQUETO. CO of the lobster, that is, by Fi§- 45- FiS- 46- alternately contracting and expanding the body, and striking the fluid with its fins and tail, as shown by Fig. 46. 161. In this stage of its progress, it takes no food, having neither mouth nor organs of digestion ; but a plentiful supply of air seems to be indispensable, and hence it floats on the surface of the water, and only descends when disturbed. In every stagnant pool, thousands of them may be seen, at the proper season, in this state of repose. Their respiratory organs are two ear-like pro- cesses shown by the adjoining figures, and these are kept above the surface of the water until another change is about to ensue. 162. Musqueto leaving the water. — When the musqueto is about to emerge, and to take the station and form of a perfect being, it stretches out its body at full length on the surface of the water, and then by some secret mechanism puffs up its skin so as to split it open at the head. As soon ,as this fissure is sufficiently large for the purpose, the insect in perfect form, appears. And now the condition of the little adventurer is critical, and per- ilous in the extreme, for, from being an aquatic, it is sud- denly transformed into an air-breather ; and after having spent all his past life as a sailor, he is in a twinkling turned landsman, perhaps far from the shore, and hav- ing no other boat but his own skin, with neither oar nor sail, for he has no use of either leg or wing. If, at this juncture, a little breeze comes on, it proves a most dreadful hurricane to the poor animal, for if a drop of water gets into the case, which has FiS- 47- now become a canoe, .it inevitably sinks and carries the insect down with it. This hazardous situation is shown by Fig. 47, which exhibits a magnified picture of the Musqueto just taking its departure into its new| element. Reaumur, who saw every thing which nature exhibits with respect to this insect 60 MECHANICAL FUNCTIONS. speaks of the peril of this moment in the following lan- guage : " When the observer perceives how much the prow of the little bark sinks, and how near its sides are to the water, he forgets for the moment, that the gnat is an insect, which, at any other time, he would destroy ; nay, he becomes anxious for its fate, and the more so if the slightest breeze plays on the surface of the water ; the least agitation of the air being sufficient to wraft the creature with swiftness from place to place, and to make it spin round and round. Its body folded in its wings, bears a greater proportion to the little skiff, than the largest mass of sail to a ship ; it is impossible not to dread lest the insect should be wrecked ; once laid on its side on the water, there is no escape. Generally, however, all terminates favorably, and the danger is over in a minute." STRUCTURE OF INSECTS. 163. Having detailed the steps by \vhich nature pro- duces a perfect insect from the egg, and shown also how these natural processes vary in several different orders and species, it is now proper to say something of the struc- ture of these beings, in order to show by what means they perform the functions of life. 164. Insects, as we have seen, and as common observa- tion evinces, vary exceedingly in their forms, habits, and dispositions, and they must consequently vary in respect to their structure, since each species must be furnished with organs and instruments by which it is precisely adapted to the situation and condition in wrhich it is placed. But although there is so much variety in their appearance, all insects consist of only three principal parts, viz, the head, trunk, and abdomen. 165. In order to illustrate this subject, we will take one of the beetle-tribe, and divide it into sections, and by means of plans show the names and uses of the several parts. The insect here represented, is the carabus sycophanta} What are the principal sections of an insect ? STRUCTURE OF INSECTS. 61 Fig. 48, and may stand as a type of all the other beetles, since they do not differ in Fig. 48. their structures. This spe- cimen is of the natural size, but the sections are somewhat magnified, that the smaller parts may be more distinctly seen. 166. The head c, Fig. 49, contains the principal enlargement of the ner- vous system, or the brain, the scull or cranium being usually the hardest part of the insect. To the head are attached the antennae, and instruments of masti- cation. The latter are much more complicated in insects than in larger animals. Those which divide their food, have a double set of jaws, called mandibles and maxilla, beside which, there are four other moveable pieces called palpi, and labial palpi. The mandibles, or upper jaws, m, cut the food ; the lower, or proper jaws, j9 mas- ticate it ; the palpi, p, and the labial palpi, /, appear to be instruments of sense by which the insect judges of the quality of its food. The motions of all these parts, are horizontal, and not vertical as with us, and other ani- mals having incumbent maxillae. To obtain an idea of the motions and uses of these parts, it is only necessary to watch an insect for a few moments while feeding. Fig. 49. 167. The trunk, or thorax, is composed of three parts, What are the jaws of insects called ? What other pieces belong to the mouths of insects ? What are the uses of the mandibles and proper jaws ? What are the uses of the palpi ? 6 62 MECHANICAL FUNCTIONS. coexisting of the three segments, figures 50, 51, and 52. The first is called the prothorax, Fig 50, to which is connected the first pair of legs. The second, Fig. 51, is called the mesothorax, and gives origin to the second Fig. 51. pair of legs and the first pair of wings, or the elytra, c. 168. The third section is the metathorax, Fig. 52. This part sustains the third pair of legs and the second pair of wings, or the wings proper, w. These two last seg- How many sections is the trunk of an insect composed of? On what principle are the limbs of insects named ? What are the names of the different parts of one of these limbs, and what are their relative situa- tions? STRUCTURE OF INSECTS. 63 merits are closely united, but the natural distinction between them is marked by a transverse line. 169. The third principal division is the abdomen. Fig. 53. This in the instance before us, is composed of six complete, and three imperfect segments, but these segments vary in number in different insects, from three or four, to twelve or more. These segments all have a ligamentous connexion with each other, allowing free mo* tion in all directions. 170. The limbs of insects are named from their supposed analogy to corresponding parts in the higher order of animals. Thus the haunch, h, cor- responds to the hip-bone of quadrupeds ; the trochanter, t, to the head of the thigh-bone ; the femur,/, to the thigh- bone itself ; the tibia, s, to the bones of the leg ; and the tarsus, r, to those of the foot. 171. It is perhaps unnecessary, in a work like the pres- ent, to give a detailed account of the peculiar mechanism, motions, and uses of each of these parts. The limbs of in- sects down to the feet, may be considered as acting in a manner analogous to our own. The feet have peculiarities to which there is no analogy in other animals, and which, therefore, must receive further notice. 172. The legs of most insects diverge, so as to reach considerably beyond their bodies on each side, thus giving them a firmer support, by throwing the centre of gravity far within the base. When the legs are very long, the insect, therefore, appears rather suspended, than supported by them, contrary to what obtains in quadrupeds and man, where the feet are immediately below the points where the legs are connected with the body. 173. In insects, the last joint of the tarsus is generally terminated by a claw, sometimes single, and sometimes double, and by which the foot is fastened in walking to any surface which is in the least degree rough, or unequal. By these hooks, insects also suspend themselves on perpen- dicular surfaces, or with their backs downward, this being By what means do insects walk on rough surfaces * 64 MECHANICAL FUNCTIONS. from the mechanism of these parts, the most easy position they can take. The beetle tribe, and the grasshoppers, are furnished with this apparatus. They cannot climb up smooth surfaces, as a polished door, or a pane of glass, their hooks being useless, without some degree of rough- ness. 174. Some insects walk by atmospheric pressure. — Other insects are furnished with a curious and somewhat complicated apparatus, by which they are enabled to walk not only upon rough, but also upon the smoothest surfaces, even with their backs downward. It is well known, that the common house-fly (inusca domestica), prefers this posi- tion to all others, for the purpose of repose. Hence we may infer, that this is the easiest position the insect can take, and therefore the one which requires the least mus* cular exertion. 175. There has been much diversity of opinion among naturalists, by what means these insects are able thus to suspend themselves on surfaces entirely smooth, with so much ease as to prefer this position for sleeping. Dr. Derham, in his Physico-Theology, speaking on this sub- ject, says, that " divers flies and other insects, beside their sharp-hooked nails, have also skinny palms to their feet, to enable them to stick on glass and other smooth bodies by means of the pressure of the atmo- sphere, after the manner I have seen boys carry heavy stones with only a wet piece of leather clapped on the top of the stone." This theory acquired additional weight, or rather was confirmed in the opinions of most entomologists by the elaborate and celebrated experi- ments of Sir Everard Home, in which he was assisted by the microscopic observations, and drawings of M. Bauer. 176. Dr. Roget, in his Animal and Vegetable Physiol- ogy, one of the most recently published " Bridgewater Treatises," has given the following description of this curious mechanism : — 177. Mechanism of the foot of the House-Fly. — In the house-fly, that part of the last joint of the tarsus, which Why cannot they walk on smooth surfaces » alltUCTUUE OF INSECTS. 65 is immediately under the root of the claw, has two suckers appended to it by a narrow, funnel-shaped neck, moveable by muscles in all direc- Fig. 54. tions. These suckers are shown in v Fig. 54, which represent the under side of the foot of the blue-bottle fly (musca vomttoria), with the suckers expanded. The sucking part of the apparatus consists of a membrane ca- pable of contraction and extension, and the edges of which are serrated, so as to fit them for the closest appli- cations to any kind of surface. In the horse-fly, each foot is furnished with three suckers. 178. Mechanism in the Saw-Fly. — In the yellow saw- fly (cimbex lutea), there are four suckers, of which one is placed upon the under surface of each of- the first joints Fig. 55- of the toes, Fig. 55. All the feet of this insect are thus provided. Both of these figures are highly magnified. 179. The mode in which these suckers operate may be distinctly seen, by observing with a magnifying glass the actions of a large blue-bottle fly in the inside of a glass tumbler. A fly, by the application of this apparatus, will remain suspended from the ceiling, with his back downward, for any length of time, without the least exertion ; for the weight of the body pulling against the suckers, serves to make them adhere stronger, for the same reason that a boy's leather sucker adheres more forcibly in lifting a large stone than a small one. For this reason it is, that house-flies prefer the ceiling to an upper surface as a place of rest. In what manner is it said the house fly adheres to the under surfaces ot smooth bodies? 6* 66 MECHANICAL FUNCTIONS. 180. Doubts concerning this Mechanism. — Notwith- standing it would thus appear, that there could be no doubt with respect to the manner in which flies are enabled to ad- here to smooth surfaces, yet some entomologists still doubt whether the feet of these insects really contain any organs which adhere by suction. If flies adhere by the pressure of the atmosphere, then, if the atmosphere be removed, it is said, they would be unable to walk on a smooth, per- pendicular surface. To demonstrate this, house-flies were put into the glass receiver of an air-pump, and the air exhausted, when it is said, " it was demonstrated to the entire satisfaction of several intelligent gentlemen present, that the house-fly, while it retains its vital powers unim- paired, cannot only traverse the upright sides, but even the interior of the dome of an exhausted receiver, and that the cause of its relaxing its hold, and ultimately falling from the station it occupied, was a diminution of muscular force, attributable to impeded respiration." In consequence of such experiments, it has been proposed to account for the phenomena observed, by the secretion of an adhesive matter with which the foot of the fly, or the hairs on it are imbued. The advocates for this mode say, that they have facts on this subject, which are quite in- explicable, except on the supposition that an adhesive secretion is emitted by the instruments employed in climb- ing. We are, however, rather inclined to the belief that these insects adhere by the pressure of the atmosphere, as was so clearly shown by the observations of Sir E. Home. INGENUITY OF INSECTS. 181. There are some traits in the characters and habits of certain insects, which appear so much like the cun- ning ingenuity, and contrivance of the higher order of animals, that we cannot see why they have not an equn! What experiment seems to make it doubtful whether flies adhere \,y i he- pressure of the atmosphere? What is the conclusion of the author with respect to the means by which flies adhere to smooth surfaces ? What is meant by the ingenuity of insects ? INGENUITY OF INSECTS. 67 claim to those attributes. We do not here allude to that instinctive endowment which guides the different species to deposite their eggs in places where the young when hatched, perhaps many months afterward, will immedi- ately find the aliment best adapted to their condition ; nor to that apparent foreknowledge with respect to time, by which there is a precise adaptation in the state of the plant to the want of the young larva; for these are mysteries of which we can say nothing, except that they are the means which the Creator has taken to perpetuate his works. 182. By the ingenuity of insects, we mean that endow- ment by which they plan and execute various structures for convenience, or comfort, and which are varied accord- ing to circumstances ; and also the devices which they employ for the purpose of entrapping, or escaping each other. 183. Ingenuity of Spiders. — Thus one species of spider constructs her net for catching game, in a place where she thinks such flies as best suit her appetite are most likely to come ; and being sensible that her presence is frightful to those insects which she would make her vic- tims, she takes the precaution to conceal herself with far more cunning than the cat, or even the tiger. The spi- der having finished its game-net, next goes to work to make a place of ambush, where it can repose in com- fort, until some poor fly, not seeing the trap, gets entan- gled in it. The place of ambush is some sly crevice at a distance from the net. In this it constructs a tube of silk, the entrance of which is no larger than absolutely necessary, and is often entirely concealed from external view. This is constructed somewhat like a sack with a small mouth, the interior being enlarged, so that the inmate can stretch out its limbs, and turn around with facility. But that the cunning insect may not be under the necessity of watching continually at the mouth of its ambuscade, it carries a cord from some convenient part of it to the net, and having carefully fastened both ends, retires to wait the result of its craftiness. The least motion of the game-net instantly brings the owner to the mouth of its ambuscade, the news being conveyed MECHANICAL FUNCTIONS. by the cord stretched between them. If it proves to be some luckless fly, which has caused the alarm, the voracious spider mounts the cord, and in another instant may be seen tying the legs, and wings of its vic- tim, with the utmost eagerness and art, so as to prevent the possibility of escape. Having thus secured its prey, it sucks its blood at leisure, and then retires and waits for another haul. 184. If craftiness, ingenuity, and contrivance, are not ex- hibited in such proceedings as these, we know not where to find them in the animal kingdom. Any one by watch- ing a common house-spider may convince himself of the truth of our statement. 185. The ingenuity with which spiders contrive to es- cape when surrounded by water, is sometimes highly curi- ous and interesting. Mr. Kirby placed a large field-spider upon a stick about a foot long set in a vessel of wrater. After fastening its thread at the top of the stick, it crept down the side until it came to the water, then immedi- ately swinging from the stick which was slightly bent, it climbed again to the top. This it repeated many times, still finding its retreat cut off, and no means of escaping in that manner. At length it let itself down from the top of the stick, not by a single thread, but by two, each distant from the other about the twelfth of an inch, guided, as usual, by one of its hind feet, one of the threads being apparently smaller than the other. When it had suffered itself to descend nearly to the surface of the water, it stopped short, and by some means not apparent, broke off close to the spinners, the smallest thread, which still adhering to the top of the stick, float- ed in the air, and wras so light as to be moved by the slightest breath. This thread catching on an object at a little distance, the spider employed it as a bridge to n. ake its escape. 186. But the ingenuity and resources of this tribe oi insects are so well known, that we will not multiply more instances. 187. Ingenuity of the Caddis-Worm. — A little insect. or worm common in fresh-water brooks, called the caddis- worm, and well known to anglers, builds for itself a INGENUITY OF INSECTS. 69 house, or tube, in which it lives, of most singular and curious workmanship. The body of this insect is composed of nine sections, the sides of which are fringed with cilia, or paddles. The legs are six, all situated near the head, as shown by Fig. 56, which represents the creature naked, or without its case. 188. It may be observed that this worm, though it is entirely aquatic, is still not well adapted to swimming. Its six legs all close together are specifically -heavier than water, and its long body beset only with a few hairs, would appear better fitted to crawl than to swim. But apparently as a compensation for these defects, the great Author of nature has endowed it with a degree of instinctive knowledge, by means of which, it is able to avoid the evils which would otherwise arise from its con- struction. 189. The caddis-wTorm constructs for itself a tube or habitation, by means of such materials as it can most easily obtain, and which are fitted to its pur- Fig. 57. pose. Leaves, straws, bits of wood, and shells are employed according to the taste, or con- venience of the builder. Fig. 57 shows one of these cases made of a few pieces of leaves, so arranged as somewhat to imitate a Spanish mantle, the head and feet of the insect pro- truding at the upper end. This, like all the other forms which it constructs, is lined with a kind of silk on the inside, and it is by means of the same substance that the different pieces of which these curious habitations are made and fastened together. 190. By Fig. 58 is shown the worm *%• 58. covered by a couple of pieces of semi- cylindrical, hollow bark, cemented to- gether. Happening to find two such pieces suitable for the purpose, it has been saved the labor of joining more, as most of its brethren have done 70 MECHANICAL FUNCTIONS. 191. Fig. 59 represents another of Fig, 59- these genuises enveloped in a riband, made of pieces of leaves joined to- gether, and rolled on like a bandage, the folds being laid with as much re- gard to symmetry and skill, as the neatest surgeon displays in dressing a limb. 192. Sometimes these mantles are constructed with small shells cemented together, as seen by Fig. 60. These shells are commonly empty, but it seems the Fig. g0. builder does not always wait for this, sometimes employing living snails, when their sizes happen to suit his wants. 193. It appears that this insect, when out of its case, can do little more than crawl along the bottom of the brook, where it lives. But when clothed in the manner represented, it floats along near the surface, or sinks toward the bottom at pleasure, generally retaining the perpendicu- lar position, but changing it to the horizontal, or turning t je head downward, at will. These different positions, as well as some motion in any direction, the insect gains by using its feet as paddles, these parts being always out of the case and free. 194. But the most wonderful point in this history is the judgment involved in the selection of materials, which, when united to the body of the insect, will exactly coun- terpoise the whole, so that it neither rises to the surface, nor sinks to the bottom, but may be made to do either by the small degree of force exerted by the feet. 195. A vast number of instances might be selected of the ingenuity, craft, and seeming discretion of the insect tribes, especially of the bee, ant, spider, and wasp, but for these, we must refer the reader to works on Entomology. What is said to be the most wonderful point in the history of the caddis- worm? PART II. VERTEBRATED ANIMALS 196. VERTEBRA, signifies " back bone, and the animals which come next to the insects in the scale of organi- zation, are called vertebrated, that is, they have back bones. 197. The animals we have heretofore examined consist of those which have no hard parts, as the 'polypi, or those covered with shells, as the mollusca, or with a crust, as the Crustacea, or such as pass from the soft to a more consistent state, as the insecta. 198. None of these animals possess an internal solid frame-work to support and connect the softer parts, this kind of structure being reserved for animals of the higher orders, and more complex organizations. 199. " If," says Roget, " it be pleasing to trace the foot- steps of nature in constructions so infinitely varied as those of the lower animals, and to follow the gradations of as- cent from the zoophyte to trie winged insect, wrhich ex nibits the greatest perfection compatible with the restricted dimensions of that class of beings, still more interesting must be the study of those more elaborate efforts of crea tive power, which are displayed on a wider field in tht higher orders of the animal kingdom. In the various tribes of beings which are now to come before us, we find na- ture proceeding to display more refined developments in What are vertebrated animals? How are the vertebrated animals espe- cially distinguished from those we have already examined? 72 VERTEBRATED ANIMALS. her system of organization ; resorting to new models of structure, on a scale of greater magnitude than before ; devising new plans of economy, calculated for more ex- tended periods of duration; and adopting new arrange- ments of organs, fitted for the exercise of a higher order of faculties. 200. " The result of these more elaborate constructions is seen in the vast series of vertebrated animals, which comprises a well-marked division in zoology, compre- hending all the larger species that exist on the globe, in whatever climate or element they may be found ; and including man himself, placed, as he unquestionably is, at the summit of the scale, the undisputed lord of the creation." 201. " A remarkable affinity of structure prevails throughout the whole of this extensive assemblage of beings. Whatever may be the size, or external form of these animals, whatever the activity, or sluggishness of their movements, whetner inhabitants of the land or water, or the air, a striking similitude may be traced in the dis- position of their vital organs, and in the construction of their solid frame-work or skeletons, which sustains and protects their fabric. The quadruped, the bird, the tortoise, the serpent, the fish, however they may differ in subordinate details of organization, yet are constructed upon one uniform principle, and appear like varied copies from the same original model. In no instance do they present structures which are altogether isolated, or can be regarded as the results of separate and independent formations." 202. Animals resist both heat and cold. — But although ere is a general analogy with respect to the skeletons of all vertebrated animals, and a general similitude in the disposition and construction of their vital parts, still there is a striking and wonderfyl difference in the effects pro- duced by the action of these parts, especially vital action, on the animal, and particularly on its temperature ; fur What is said concerning the affinity of structure which exists amont> all animals with back bones? What is said of the different effects of vile I action on differant vertebrated animals' VERTEBRATED ANIMALS. 73 while the fishes, properly so called, partake the tempera- ture of water in which they live, even to the point of freez- ing ; air-breathing animals have the power of resisting both heat and cold, and of preserving nearly the same temperature, whatever that may be in which they are placed. + 203. It is perhaps true, that to a certain degree, all animals, and even trees, resist both heat and cold so long as the vital principle remains active. But in the lower orders of animals, this power is exceedingly feeble when compared with that which endows quadrupeds and man. 204. Thus eels become as cold to the touch as the ice in which they may be preserved, and yet the vital princi- ple remains, since these creatures may be thus kept in a torpid state, probably for any length of time, and then again revived to life and activity. It is well known, also, that the gold-fish may be frozen with the water in its vase, and yet by a slow application of heat, become as lively as ever, in the course of half an hour. In these cases, and many others which will be mentioned hereafter, life is suspended, but its principle remains, and although such animals do not preserve their temperature like those of the higher orders, they are still endowed with a much greater tenacity of life, for with a few exceptions, when a warm-blooded animal becomes cold, the vital principle is not merely suspended, but is extinct, and death en- sues. 205. The power of man, and also of quadrupeds and birds, to resist changes of temperature, is indeed surprising. With respect to the power of animals to resist low degrees of temperature, every one who resides in a cold climate, has seen abundance of natural examples. The turkey, for instance, will sleep comfortably, perched on a high tree, entirely exposed to the northern blast, when the thermom- eter is thirty degrees below zero. Allowing the tempera- ture of the bird to be one hundred degrees, which is not above the truth, then there is a difference of one hundred What is said about the freezing of eels and fish? What animals have the greatest tenacity of life, cold or warm-blooded? What difference sometimes exists between the temperature of the turkey and the air in which he is? 7 74 VERTEBRATED ANIMALS. and thirty degrees, between that of the atmosphere and that of the turkey. But the black captitmouse, a little bird which passes its winter with us, is a much more ex- traordinary instance of the same kind, on account of its diminutive size. This bird, as it flies, does not probably weigh more than half an ounce, and yet, small as it is, thetvital action with which it is endowed, is sufficient to maintain its temperature one hundred and thirty or one hundred and forty degrees above that inwThich it is placed, and this difference, so far from inducing torpor, seems from the cheerful and lively appearance of the little animal, to be a temperature most agreeable to it. 206. On the contrary, it is found by accurate experi- ments, that the animal system is capable of resisting de- grees of heat in a much greater proportion above its own temperature, than these are below. 207. Order of the Experiments on the power of man to resist Heat. — A circumstance which happened in France, in the year 1760, first led philosophers to make experiments on the power of the human system to resist high tempera- tures. Some gentlemen having occasion to use a public oven for certain experiments on the day in which bread had been baked in it, and wishing to ascertain its tempera- ture, a girl, one of the attendants at the bakery, offered to go in and mark the height of the mercury with a pencil. The girl smiled at the hesitation of the gentlemen to allow her to do so, and going into the oven, marked the temperature at 260° of Fahrenheit. Notwithstanding the anxiety they felt for this young salamander, she declared to their astonishment, that she felt no inconvenience from1 the heat, and insisted on staying longer, and having re- mained ten minutes, the thermometer then was found to stand at 288°, that is, 76° above the heat of boiling wa- ter, and 190° above the ordinary temperature of the hu- man system,which is 98°. 208. Experiments of Sir Charles Blagden and Dr Fordyce. — The publication of these facts excited, general What circumstances first led philosophers to make experiments on the power of the human system to resist heat? How much higher was the temperature of the oven than that of the ordinary human system ? VERTEBRATED ANIMALS. 75 attention, and several philosophers made experiments on their own persons with a view of testing and explaining such a singular phenomenon. Of these experiments, probably the most accurate and decisive, and certainly the most famous, were those of Sir Charles Blagden and Dr. Fordyce. The room where these celebrated experi- ments were made, was heated by flues, there being neither chimney nor any other aperture where the heat might escape. 209. In the first experiment, Sir Charles went in, with wooden shoes on his feet, the heat being a little above that of boiling water. The first impression is described as exceedingly disagreeable, but in a few minutes all this uneasiness was removed by the breaking forth of a pro- fuse perspiration. Having stayed twelve minutes, he came out with a sense of fatigue, but nothing more, the ther- mometer then standing at 220°. 210. It was afterward found that the temperature of 260° could be endured for a short time, without much diffi- culty. But the most curious part of these experiments were the sensations produced by touching their own persons on some vital part, or touching each other, and also objects in the room. Every piece of metal about their persons, as their watch chains, became intolerably hot; small quantities of water placed in metallic ves- sels, boiled in a few minutes. Though the air of the room was 260°, it could be taken into the lungs with impunity, but the boiling water in which the thermome- ter indicated only 212° scalded the finger as usual. Eggs and beef-steak suspended in wire nets, were com- pletely done in from five to fifteen minutes, and still the gentlemen were able to remain in the room. But not- withstanding dead matter became heated to the tempera- ture of the air, as was expected, the persons of the gen- tlemen never rose higher than about 101°, or at most 102°, as indicated by the thermometer, with the bulb placed on the tongue, or under the arm. 211. The hands being at a distance from the vital parts, were heated to a much higher degree, so that when the What were the degrees of heat to which Sir C. Blagden and Dr. For- dyce exposed themselves? 76 VERTEBRATED ANIMALS. gentlemen touched any part near the seat of life, as the tongue or side, it felt nearly as cold as a piece of ice under ordinary circumstances. Thus though these per- sons were in a temperature of 260°, and even in some exper- ments as high as 264°, the heat of their bodies never rose higher than 102P making a difference of 160° between them and the air in which they were placed. 212. In what manner the heat is carried off". — If we look for the means which nature displays to carry awray the superabundant heat to which the system is exposed, we shall find that perspiration is the most obvious, though not the only one to which we can refer. The boiling water in the rooms in which these experiments were made, as is the case everywhere at the surface of the earth, never exceeded 212 degrees, the remaining heat being carried off by the steam rising from its surface. In like manner the gentlemen state, that within a few moments after entering the heated room, their persons were covered with a profuse perspiration, which contin- ued as long as they stayed. But beside this cause, the operation of heated air on the system is not so great as might be expected in consequence of its being so highly rarified and expanded, that comparatively few particles came in contact with the surface of the body. It has been found also, that the quantity of oxygen consumed by the lungs (which is' the source of animal heat), during these experiments, is much less than ordinary, most proba- bly owing to the rarity of the air. 213. It appears that these are the several causes which conspire to keep the temperature of the animal system nearly the same as ordinary, when exposed to high de- grees of heat. STRUCTURE OF THE BONY, OR OSSEOUS FABRIC. 214. The framework of all vertebrated animals is made of bone, the appearance of which we need not describe. What are the means employed by nature to resist high degrees of heat? Why is the temperature of "boiling water stationary at 212 de- grees? STRUCTURE Ob' THE BONE. 77 215. The composition of bone is chiefly phosphate of lime, cemented into a solid form by animal matter. On exposure to heat, bone becomes black, in consequence of the conversion of this animal matter into charcoal. In the meantime the oil contained in the cavities takes fire, and all the combustible materials of which the bone is composed, are consumed. It now becomes white and porous, having by the process lost about half its weight. What remains, being, as it were, the skeleton of perfect bone, is phosphate of lime deprived of its animal cement. It is now so brittle as to be broken by a light blow, or even ground to powder in a mortar. On breaking the bone across, we are now able to discover the cavities which contained the oily matter, and probably also some of those which contained the animal cement. 216. On the contrary, by steeping a bone in a quantity of acid, sufficiently diluted to prevent its action on the ani- mal matter, we may deprive it of its phosphate of lime, and preserve this matter entire. The substance remain- ing after the solid matter has been dissolved, retains the exact form of the bone, but is soft, flexible and elastic ; and is resolvable into a jelly by boiling. This substance is very nourishing, and is that which forms the soup made from bones. 217. The different mechanical purposes for which the bones of the living system are employed, require that they should be of a great " variety of forms. Thus the spine, or principal support of all the vertebrata, requiring motion in all directions, is made up of a great number of pieces, joined together by a layer of cartilage between each two, which, by its elasticity, allows of the required motions. The wrist and ankle are also composed of many pieces each, also allowing of general motion. On the contrary, the limbs acting as a system of levers, con- nected by joints, are composed of solid, firm pieces, gen- erally of a cylindrical form, and of considerable length, having motion only at the points of connection. Lev- What is the composition of bone ? Why does burning bone become black? Why does burnt bone become white ? When a bone is steep- ed in 'acid, what part of its composition is destroyed? What is the ap- EeaYance and what the consistence of the bone, when the phosphate of me is destroyed ? What is said of the different forms of bones f 7* 78 VEilTEBRATED ANIMALS. ers of various kinds, most artificially and beautifully com- bined are found in the limbs of quadrupeds, the wings of birds, and the fins of fishes. The construction of these bones combine strength and lightness to an admirable degree, being hollow cylinders, with the enlarged end porous. 218. All the long bones of quadrupeds, birds, and man, are made on this principle. When we come to the physi- ology of the birds, we shall find a wronderful provision in that particular class to ensure lightness, the bones being thin cylindrical tubes filled with air. 219. In the corresponding bones of quadrupeds, the interi- or is filled with an oily substance Figs. 61 and 62. called marrow, which is entire and undivided along the shaft, or small- est part of the cylinder, but is con- tained in pores toward the two ex- tremities, w^here there is a spongy expansion of bony matter, for the purpose of strengthening the enlarg- ed size of the bone at these pails. Fig. 61 represents a longitudinal section of the femur, or human thigh bone, showing the dense, solid substance of the external parts, and the cavernous and spongy structure of the interior. Fig. 62 shows a" similar section of the humerus, or bone of the arm which joins the shoulder. It is said by mechanical philosophers, who have made ex- periments on this subject, that it would have been impossible to have otherwise formed with the same quantity of solid matter, a lever so strong, and yet so light, as that presented by the long bones of the quadrupeds and man. What is said of the construction of bones which are used as levers ' Give a description of the structure of the two bones shown by Figs. 61 What is said of the mechanical strength of the long bones ? FORMATION OF BONE. 79 FORMATION AND GROWTH OF BONE. 220. IN the earlier stages of animal growth, there is formed in those parts of the system which are ultimately to be supplied with bone, a cartilaginous pattern in miniature of the bone itself. This cartilage is semi-hard, somewhat tenacious and translucent. When the bone begins actually to form, the cartilage becomes absorbed at the centre of the piece, and a few ossific particles are deposited in its place. As the process goes on, cartilage continues to be taken up, and bone formed in its room from the centre toward the circumference, or extremities, until the whole becomes ossified. 221. In the cylindrical bones the process begins in the middle of the cylinder, forming a ring there, which in- creases in both directions, until the whole becomes bone. Several of the bones of animals, particularly those of the scull, are not completely formed until the animal is of con- siderable age. 222. The heads of the bones are formed independently of the shafts, being separate pieces with a thin layer of cartilage between them. Afterward these parts unite, the cartilage being replaced by bone ; but this does not happen in our species until the age of fifteen or eighteen 'years. 223. The bones are well supplied with blood-vessels, which enter about the middle of the long bones, and pene- trating the central cavity, pass both upward and down- ward, supplying the substance of the bone with small branches, and giving off some very delicate arteries which secrete the marrow. It is the arteries which thus pass into the bones, giving off the most delicate fibres through every part of its substance, that secrete and form the bone itself. 224. Every bone is surrounded by a thin membrane, called the periosteum*, from which pass into the external, and most solid part of the bone, thousands of fine blood- vessels by which this part was formed, and is still nourished, In what manner is it said bones are formed ? Are the long bones of young animals formed of one, or several pieces? Are the solid parts ol bones supplied with blood-vessels or not ? What is the membrane which surrounds the bones called ? 'What vessels deposite or secrete bone7 VERTEBRATE!) ANIMALS. as is proved by the fact, that the destruction of the peri- osteum, causes the death and decay of the part over which it was placed. SPINE OF THE VERTEBRATA. 225. The word spine signifies a thorn ; this part of the skeleton being so called, because each piece of which the back bone is formed, has a projecting process outward, making as a whole that prominent ridge so well known as the spine in various animals. Thus by common consent, and long usage, a column made up of many pieces, is not only named after a sharp-pointed instrument, but is spoken of aS a single bone. 226. This column in the human species, consists of twenty-four distinct bones, named vertebra, from the Latin vertere, to turn, because this part of the skeleton has motion in every direction. 227. Of these twenty-four pieces, five belong to the loins, twelve to the back, Fis- 63- and seven to the neck. The whole spinal column is represented by Fig. 63, of which the pieces above 2, and below 1, belong to the neck and loins ; while those between, belong to the back. 228. The spine is the foundation, or chief mechanical support of the whole skeleton ; and riot only so as giving pro- tection to the spinal cord, wrhich in one sense is a part of the brain, being a con- tinuation of its substance, but is a very essential part with respect to the nervous system. 229. A single vertebra is shown by Fig. 64, where the lower part, or body, which is somewhat radiated on the surface, is that by which it is joined to its fellow. The elongation s is called the spinous process; and is that which,when the whole are in place, forms the ridge of the spine, pr back. Beside this, there is another pro- jection, t, on each side of the base of the SPINE OF THE VEKTEBRATA. 81 arch on which the spinous processes are FiS- 64- situated. These are called the trans- verse processes of the vertebrae. The arch formed by the united bases of these processes, and a groove in the body of the vertebra?, form the canal through which the spinal marrow passes. This aperture through a single vertebra, is obvious in the adjoining figure. When all are united, they form a continuous canal with solid walls, for the protection of that most important part of the animal system next to the brain, the spinal marrow. 230. The spine is the great central beam of the whole fabric of the skeleton. To this part all the other bones are connected by muscles and joints, the whole being thus combined into a general frame-work. It is the common axis of all the motions of the limbs, by furnishing fixed points for the attachment of all the larger muscles. 231. Nowhere has the mechanical art of the Great Architect of Nature been more skilfully displayed than in the construction of this part of our frames. Had the spine been made of a single rigid piece, it would be lia- ble to fracture by blows which it now withstands with impunity; and besides, such a construction would have deprived us of a great variety of motions, which are now so important to us in the business and comforts of life. 232. Between the bodies of each bone there is an elas- tic cartilage, allowing of a little motion in all directions ; and this slight flexure in each part, being multiplied through the whole column, admits of sufficient motion for all our purposes. 233. In addition to the cartilaginous connection, the spi- nal bones are bound together by strong ligaments and mus- What does the word spine mean ? Why is the back bone called spine ? How many bones does the spine consist of? How are these bones divi- ded, and what names are given to each division ? What is said of the mechanical importance of the spine ? What very important part does the spine protect ? Which is the spinous, and which the transverse pro. cesses of the spine? What most important portion of the system is pro tected by the spine? What is said of the importance of the spine, as connected with the other parrs of the bony fabric ? What would have been the consequences, had the spine been formed of a single :>'ece ? How are the several pieces of the spine connected together ? o2 VEBTEBRATED AMMALS. cles, passing from one process to the other, through the whole line, thus combining the twenty-four pieces into one entire and firm column. 234. It is by the action of these muscles, thus passing longitudinally along the spine, that we are enabled to bend it backward and forward, or from right to left. Thus the back is made hollow, or bent backward, when the muscles attached to the spinal processes are contracted j and when those attached to the transverse processes are contracted on the one side, and relaxed on the other, then the column is bent from the right toward the left, or the contrary, as the case may be. Fig. 65. 235. The connection of the spine of the human frame with the ribs and arms, is shown by Fig. 65. The ribs are How is the spinal column made to bend backward, or from right to left? SPINE OF THE VERTEBRATA. generally twelve in number on each side, though jn some instances they are found to be thirteen, and more rarely only eleven. They are distinguished into true and false ribs. The seven upper ones, which are artic- ulated, or joined to the sternum, c, are called true ribs, while the five lower ones, which are not immediately attached to the sternum, or breast-bone, but to a cartilage connected with it, are called the false ribs. The other extremities of the ribs are articulated by small heads to the vertebrae, and secured by a ligament, so as to allow of a small motion upward and downward, but in no other direction. 236. The use of the ribs is to give form to the thorax, to cover and defend the lungs and heart, which are situ- ated within them ; and also to assist in breathing, by their alternate elevation and depression. 237. The sternum, c, or breast-bone, it is well known, h situated in front of the thorax. In young people, this bine is hi several parts, united by cartilages ; but as we advance in life these cartilages ossify, or are changed into bone. Its shape is oblong, and its external surface convex. To its edges are immediately articulated the seven upper ribs. 238. The clavicle, b, has its name from the Latin clavis, which appears to come from clando, to shut, this bone resembling in shape an ancient key. It is usually called the collar bone, and is placed at the upper part of the breast, or root of the neck, extending across from the tip of the shoulder to the upper part of the sternum. It is a round bone, curved, somewhat into the shape of the italic S. It supports, and maintains the shoulder in its proper place, and prevents it from falling forward toward the breast. Its outer end is firmly fixed to the upper part of the scapula, or shoulder-blade. Animals which employ their fore feet as hands are furnished with this bone, as the monkey-tribe and squirrels ; while those What is the number of ribs in the human skeleton? How are they listinguished ? To what part are the seven upper ribs articulated in front ? How are the anterior ends of the five lower ribs secured? How are the posterior ends of all the ribs secured ? What are the uses of the ribs? What is said of the sternum? Whence is the name clavicle? What is the common name of this bone ? To what parts is the clavicle articulated? What animals beside man have this bone? $4 VEllTEbKATED ANIMALS. which make no such use of their feet, are without it, as the horse and sheep. The bones of the arm are the humerus, d, and the radius, and ulna, e andy. 239. The humerus is a long cylindrical bone, with its upper end articulated to the scapula, forming the shoulder joint. - At the point of articulation, the extremity is en- larged into a round, smooth head, which is admitted into the glenoid, or shallow cavity of the scapula, where it is strongly secured by ligaments, but in such a manner as to allow it motion in all directions. 240. At its lower extremity, the humerus is gradually expanded, for the articulation of the two bones of the fore- arm, the radius and ulna, both of which are connected with this bone at their upper extremities, forming the elbow joint. 241. The mechanism of the elbow joint, as well as the action of the muscles on the radius and ulna, together with the mechanism and wonderful powers of the hand, will be reserved for another place, while we proceed to an .account of the spines of other vertebrated animals The whole number of bones in the human species amount to 240. 242. Unity of design manifested in the Constitution of the Spines of Vertebrated Mnimals. — It is a truth, as won- derful as it is instructive, which the study of nature de- velops, that although the Creator had almighty power and infinite wisdom, and might, therefore, have varied his plans, and executed his designs, in an infinite number of ways, in the construction of the different races of animals, that we still find an economy of design, and a unity of plan in the general construction of the frame- work, or foundations of the grand divisions of animals, which prevails throughout all the orders, or sub-divisions, however different the destinies, or habits of the distinct races may be from each other. Reasoning and judging on this subject as we do with respect to the arts of man, What, are the bones of the arm called ? What joint is formed bv the S?1NE OF THE VERTEBRATA. 85 we should be led to suppose that the frame-work of our own species had first been constructed, and that the cor- responding parts of other animals had been varied from this, only so far as their means of existence, habits, or the element in which they were destined to live, made it abso- lutely necessary. 243. We have p1 :eady stated that the spine is the main column, or IDT,! substantial part of the skeleton of verte- brated animals, and we have described and figured this part as it exists in our own frames. We will now show the unity of design which exists in the construction of the animal kingdom, by comparing the spines of other animals, with that belonging to the human frame. 244. Mechanical elements in the Vertebra. — The num- ber of elements, or mechanical parts which enter into the composition of the vertebrae of different animals is shown by Fig. 66. This does not represent the precise form of any vertebra, but is meant to com- bine the elements of the corres- ponding parts as existing in verte- brated animals generally. The first part is the nucleus or body of the vertebrae 6, which is present in all the species. Next in import- ance is the bony plates, or leaves, as they are called, /, /, which pro- ceed from the sides of the body, and embrace the spinal marrow, which runs through the aperture between them as shown in the figure. Another essential element is the spinous process, s, which unites the two plates, and thus completes the superior arch, of which it may be considered as the keystone for the pro- tection of the spinal cord. Then come the two transverse processes, t, t, which extend outward, toward the sides, and with which the ribs, r, r, are generally connected. Fig. 66. Explain Fig. 66. Point out the parts that are essential to a vertebra. 8 V •• VERTEBRATED ANIMALS. These are the six parts which comparative anatomists con- sider the elements of the vertebrae, and which are found in most vertebrated animals, however various in form, size, or habits, they may be. In some cases, however, in addi- tion to these, there is the process f, bifid at the base, and forming a spine at the lower surface of the vertebrae, or opposite to the spinous process. This structure is common in the fishes. The aperUr~ forced by the bifurcation of this process, admits the passage of a large artery. 245. As our plan will not allow an extension of this part of our subject to the different orders of the veile- brata, we will omit any illustration from the quadrupeds, as being most nearly allied to man in the scale of organi- zation, and therefore most likely to present similar spines ; and since illustrations the ntost remote from man in the scale of being, will tend most clearly to show a unity of plan in the construction of the whole, we will give examples from some of the lower orders of vertebrated animals. 246. Vertebra of Fish. — Fig. 67 represents a section of a part of the spine of a fish Fj 67 standing in the natural position. The foody of each vertebra is hollowed out on both sides so as to form cup-like cavities; by which means when the two con- vex cavities are applied to each other as in the living animal, a cavity having the shape of a short double cone is formed, as shown in the figure. These cav- ities left by the bones, are filled with a gelatinous substance which is nearly incompressible, and which appears to serve as a kind of pivot for the motions of the joint. By dividing a spine in the centre, these parts are seen as shown in the figure. 247. A single vertebra is represented by Fig. 68, for the Explain Fig. 67. What is the difference between the vertebrae of quad- rupeds and fishes ? SPINE OF THE VERTEBRATA. 87 purpose of showing the peculiarity of this part in the fish, and which forms one of the elements of Fig. 66, which is marked f. In the vertebrae of the fishes, therefore, we see the two spinous processes, ff? stand- ing opposite to each other, the one above and the other below the body, while the trans- verse processes are wanting. These are the points of difference between the spines of this class of animals, and those of the land verte- brata. 248. The design of this difference will immediately be- come obvious, if we stop for a moment to inquire what sort of motion in the spine is best calculated to impel the fish through the element where it lives. The spines of the vertebra? standing in a vertical position, when the fish is in its usual posture, all vertical motions, or flexures of the spinal column upward and downward, is entirely prevented, the motions being limited to flexures from side to side. Now, since the fish moves through the water on the same principle that a boat is propelled by what is called sculling, that is, by a single oar moved backward and forward in the stern, it is plain that any compound flexure of the spine would rather retard than facilitate its progress. 249. Locomotion of Fishes. — The manner in which fishes give themselves progressive motion through the water will be understood by Fig. 69. Suppose that the tail is curved to the right, as / shown in the figure, and in this situa-'2"' tion, the muscles on the left side act suddenly, so as to bring the fish into a straight line, then the reaction of the water against the motion of the tail in the direction of r, p, would give the whole body an impulse contrary to that of the reaction, and the centre of gravity c, would move in the direction of c, 6, which is parallel to p, r. This impulse is not destroyed by the next flexure of the tail in the contrary 88 VERTEBRATED ANIMALS. direction, because the principal force exerted by the muscles has already been exerted in the motion from r to m, in bringing the tail in a straight line with the body ; and the force winch carries it on to /, is much weaker, and therefore occasions but a feeble reaction of the water. When the tail has come to /, a similar action of the muscles on the other side, will give an impulse in the direction of /c, /, and a motion of the whole fish in the same direction, that is, in the line c, a. The flex- ures, and consequent re-action of the tail being repeated in quick succession, the fish moves forward in the diagonal of c, d, intermediate between the direction of the two forces. 250. By bending the whole body almost to a circle and then suddenly straightening it, fishes are able to leap out of the water, or to ascend a perpendicular cataract of con- siderable height. 251. Did the plan of this little work allow an extension of the subject of this section, it could be shown that the spines of the frog, tortoise, birds, and indeed all other vertebrated animals, present a striking similarity in their structures, and that their forms, lengths, and peculiarities, are deviations from the general plan we have described, only so far as is necessary to adapt them to the general organization of the animals to which they belong. How- ever ignorant any one may be of anatomy, he will gene- rally distinguish the back-bone of any animal without mistake, so great is the similarity in all. STRUCTURE OF BIRDS. 252. In np class of animals is the structure of the seve- ral parts so obviously adapted to the uses for which we see them employed, as in the birds. In these animals, the frame of the skeleton, the figure, position and construc- tion of the wings, the size of the muscles ; the lightness of the whole system when compared with the size, to- In what directions does the spine of a fish allow of motion? Would any other motion assist the fish in its progress? Explain Fig. 69, and show in what manner the fish gains progressive motion through the water. What is said of the peculiar adaptation of the construction of birds to the element in which they move ? STRUCTURE OF BIRDS. 89 gether with the positions and strength of the quills, and feathers, all have a direct and beautiful relation to the properties of the elements in which they are intended to move. 253. In no part of creation, therefore, do we see more direct and positive marks of design in the Great Author of Nature, in the adaptation of means to specific ends, than in the construction of birds. 254. What is particularly striking in the skeletons of these animals when compared with others, is the vast size of the sternum, or breast-bone as seen atjf, Fig. 70. This bone not only covers the whole chest to a considerable depth on each side, but extends back nearly to the in- sertion of the legs. Its lower part forms a deep perpen- dicular crest, shaped, it is well known, like the keel of a ship, the whole being remarkably thin and light, when compared with the extent of its surface. The design of this great development is obviously to furnish an exten- sive surface for the attachment of the pectoral muscles to be employed in the motions of the wings. In many birds these muscles outweigh all the others of the body put together, and it is owing to their great power that the eagle and other birds have such amazing strength of wing, as to carry animals heavier than themselves, and that the swan sometimes breaks a man's leg by a single flap of his pinion. 255. But in addition to the general appearance of light- ness, which the bones of birds present, the cylindrical ones are hollow tubes filled with air. In this they differ from all other living bones, those of other animals being filled with marrow. 256. The lungs of birds are placed on the ribs, between which their substance also projects. — They are of a compact texture, and so bound down to their places among the ribs, as to have no expansive and contractile motion, like those of other animals ; hence respiration in this order is carried on by alternately enlarging and contracting the cavity of the chest, as will be explained For what purpose is the breast-bone peculiarly large in the birds ? With what substance are the bones of birds filled f In what manner is respiration carried on in birds ? 7* 90 VERTEBKATED ANIMALS. in another place. The air not only circulates through the lungs by this means, but also penetrates the cavities of the bones through vessels constructed for this purpose. In birds not formed for extensive flight, this provision, however, is much less extensive than in others. Thus in the domestic ^>wl> the humerus, or first bone of the wing, is the only one filled with air. But in the eagle, and other tribes, which spend much of their lives in the air. nearly all the bones are hollow, and are filled with the element in which they live. The air thus admitted becomes considerably rarefied by the temperature of the bird, by which provision the whole body is rendered considerably lighter than it otherwise would have been. 257. In all this we cannot but observe a wonderful adaptation in the construction of the animal, to its habits, and the element in which it lives. 258. Structure of the Back-Bones of Birds and Fishes. — In the structure of the two classes of vertebrata, the birds and fishes, we may trace remarkable differences which are obviously dependant on the adaptation of each to the elements in which they are respectively des- tined to live. In the fish, the chest and all the viscera are placed as far forward as possible ; the respiratoiy organs, which are the gills, and the heart being also close to the head. Thus the bulk, and consequently the cen- tre of gravity, being placed near the head, the tail is left light and flexible for the purpose of motion. In the fish, the neck, or rather that portion usually occupied by the neck in the other classes, Disappears, its place being filled with those parts usually found in the chests of other ani- mals. 259. In the birds, on the contrary, the viscera are pla- ced as far back as possible, and a long flexible neck is contained between the trunk and head, so as to place them at a considerable distance asunder. In fish, progressive motion is effected by the tail, the impulse being given by its horizontal flexures from one side to. the other. In What difference is there in the different kinds of birds with respect to the quantity of air contained in their bones? What remarkable differ- ence i-s *here between the construction of birds and that of fishes? STRUCTURE OF BIRDS. 9\ the birds, the instruments of motion are fixed to the fore- part of the trunk, the impulse being given by the verti- cal, or up-and-down action of the wings at the same in- stant. In the fish, the spine is flexible, especially tow- ard the tail, while in the bird this part is rigid through the body, having motion only in that part wrhich forms the neck. 260. Birds change the Centre of Gravity. — It is by means of the neck, that the bird is enabled to change its centre of gravity, according to circumstances. In the act of flying, this centre must be between the articulations of the wings ; while in resting on its legs, it must be between the feet. Had not birds the power of adjusting the centre of gravity, they could neither fly with precision through the air, nor rest secure on their feet. Fig. 70. 261. Skeleton of a Swan.— The skeleton of a swan represented by Fig. 70, will not only serve to show in 92 VERTEBRATED ANIMALS. what manner these changes with respect to the centre of gravity are affected, but also how nearly the bones of birds correspond with our own. The neck of this bird is composed of twenty-three bones, most of them so articu- lated together as to allow of free motion in all directions. By extending this part in a straight line, the bird while flying, moves the centre of gravity so as to bring it to some point between the insertions of the wings, whereas, while the swan is floating on the water, or resting on the feet, the neck is thrown backward and curved into the form of the letter S, by which the equilibrium of the whole system is preserved by throwing the centre of gravity be- tween the feet. On the same principle all other birds are enabled to preserve their equilibria in any position they choose to take. 262. Comparison between the Bones of Men and Birds. — We have already shown that there is a general simili- tude in the skeletons of all the vertebrated animals, and especially in their spines. At first view it would hardly be thought that there could be much similarity between the bones of a bird, and those of a man, and yet on a closer examination, we shall find that the general principles of structure are the very same, and not only so, that some of the individual bones approximate each other in form. Thus the humerus, of which a, Fig. 70, is the head, has a general form like 4hat of our own species. It is flat- tened in the same manner at the lower extremity for the articulation of the two bones, the radius and ulna. The two latter bones, 6, with which the humerus forming the elbow-joint, are also the same in number, and some- what similar in shape to those forming the corresponding part of the human skeleton. The carpus, or wrist, c, con- sists of only two bones, the one articulated with the radius, the other with the ulna. These move together as one piece. The metacarpus, or hand, d, also consists of two bones, but these are united so closely as to form only one in effect and use. Below these, at e, there is a little projecting bone which may be considered as a rudi- mental thumb. 263. The prehensile organ in birds being the bill, and ANIMAL FUNCTIONS. 93 85 nature never furnishes any organs but such as are abso- lutely necessary, so the terminations of the wings of birds, instead of being furnished with bones and mus- cles which have the prehensile power, like the hand, are only provided with such as are fitted for the insertion of quills. PART III. ANIMAL FUNCTIONS. 264. THE Vital Functions, or actions of animals, are such as are immediately essential to life, as the circulation of the blood, respiration, secretion, and absorption. With- out these the animal cannot exist. The Animal Functions are those which support and renovate the system, and without which the vital functions could not long be maintained, as digestion, nutrition, and the formation of chyle. These are not immediately essential to life, but may be suspended for a time. The Mechanical Func- tions are such as depend on the will, as the action of the muscles, whether employed for the purposes of swim- ming, flying, or walking. The instruments by which mechanical action is effected have been the chief sub- jects of the foregoing pages, and we shall now proceed What are the vital functions of animals ? What are the animal func- tions ? What are the mechanical functions ? 94 ANIMAL FUNCTIONS. to treat of the animal functions, reserving for future con- sideration the action of the human muscles, which can be most properly noticed when we come to speak of physical education. SOURCES OF NUTRITION. 265. The nutrition which nature has provided for the various tribes of animals, is derived, entirely, from two sources, namely, from the animal and vegetable king- doms. But as the carnivorous tribes derive their food from those which are herbivorous, the nourishment of all is ultimately derived from the earth itself. 266. Vegetable Food. — The economy of nature is no- where more wonderfully manifest than in the adaptation of animals to the consumption of every kind of nutrition, there being hardly any organized substance which does not furnish food for some living creat* ire. The succu- lent parts of vegetables are not only the chief source of nourishment of the greater proportion of the larger ani- mals, but also serve the same purpose to myriads of insects. Many tribes of birds, likewise, live on vegeta- bles, but insects become the food of the larger number, while riot a few are strictly carnivorous. But while these substances are the common food of the most numerous races, even the hardest parts of vegetables, and the most poisonous plants serve the same purpose to certain other tribes. The larvse of various insects live by eating their way through the diseased portions of timber logs ; while the nettle, the deadly night-shade, the henbane, and other acrid and poisonous plants, afford wTholesome food to several species. Some live on fruits and seeds, and others on the juices which they pump from succulent plants. 267. Minimal Food. — But while a vast number of tribes thus subsist on the fruits of the ground, these in their turn "become the prey of at least as great a number of Whence do animals derive their nutrition ? What is said of the ex- tent to which vegetables serve as the food of animals? SOURCES OF NUTRITION. 95 carnivorous animals. Every part and portion of the earth's surtace ; every tree, every building, every room in which we live, and even the atmosphere which we breathe, con- tain a greater or less number of beings, which are perpetu- ally on the- alert to procure victims for their voracious appetites. From the spider, which " taketh hold with her hand, and liveth in king's palaces," to the lion which prowls over the deserts of Africa, there is an uninterrupted series of carnivora, ready to suck the blood of any living thing they can master, 268. We can see, and shudder at beholding the formi- dable arms of the lion, and tiger, and can observe the murderous disposition of the cat. But there are thousands of insects which lie in wait for their prey, and which emulate the feline race in their savage dispositions, which fall under the observation of none except naturalists. Many of these, when only a few hours old, begin to hunt for their prey, and continue during their lives, to subsist only by war and bloodshed. Many of them are cannibals, devouring their own kind, or even their own families, without hesitation, when other food does not come in the way. Nor are many of the inhabitants of the water, whether fresh or salt, less predacious in their dispositions. From the larva, that is cojitented with the stagnant pool by the roadside, to the shark, that roams through the wide ocean, there exists a continued series of animals, not less rapacious in their dispositions, and even more voracious ih their habits, than the corresponding series which inhabit the land. 269. Many of the carnivorous tribes insist upon killing their own food, and will touch nothing which they find already dead ; while others are too indolent to live by the chase, and are contented to devour anything that once had life, in whatever state they may find it. 270. In the absence of the larger animals, myriads of insects are ever ready, in the warmer seasons, to devour any dead animal, no matter in whatever place it may be found. 271. So strongly was Linnaeus impressed with the im- mensity of the scale on which the work of demolition was What is said of carnivorous animals and their food ? 96 ANIMAL FUNCTIONS carried on by insects, that he used to maintain that the carcass of a horse would not be devoured by a single lion, as soon as it would by three green flesh flies (rtnisca vomitoria), and their immediate progeny ; for it is known that one such fly will lay twenty thousand eggs, which in the course of a single day will produce larvae, each of which will devour so much food, as in another day to in- crease its weight two hundred times ; and each of these twenty thousand in the course of a few days more, will produce a third generation equally numerous. 272. Relation between the Organization of Animals and their Food. — Thus we see that one race of animals is des- tined to become the food of others, and these again are in their turn consigned to the same fate from their more powerful enemies. Each kind, whether they subsist on vegetables or flesh, are so organized as to digest the food which their appetites crave. The peaceful cow and sheep are contented with cropping the blades of grass from the field, because their organs of nutrition are fitted for the digestion of this kind of food and no other. But the lion, the tiger, and all other carnivorous a imals, are organized only for the digestion of flesh, and can no more live upon herbs than the cow and sheep can sub- sist upon each other. Hence the Creator has provided these animals with claws to secure their prey, and cutting teeth to tear and divide it ; and since this is the only. mode by which such animals can live, we are no more at liberty to treat these races with cruelty, because they tear other animals in pieces, than we have to maltreat the cow because she crops the herbage of the field. 273. Man omnivorous. — But while one class of the animal kingdom are herbivorous, and another carnivorous, from their structure, the lord of the creation has a stom- ach, and a general organization, which, so far as food is concerned, embraces both these classes ; and hence man What is said of cruelty toward the predacious animals ? How may animals be divided with respect to their subsistence ? ANIMAL NUTRITION. 97 may be called, as he strictly is, the omnivorous, or all-eat' ing animal. ANIMAL NUTRITION. 274. When we examine the structure of the very low- est orders of animal existences, we find, that whatever other parts may be wanting, whether they be eyes, or ears, or nerves, or brain, or organs of locomotion, two parts are always present, to wit, a mouth and stomach. Without these, no animal can exist, for however com- plex the organization in other respects may be, nothing can compensate for the organs of nutrition. From the account we have given of the structure of the hydra, it would appear that nearly every other part usually con- stituting an animal may be dispensed with, except these ; and that some of the polypi consist of little or nothing more than a throat and organs of digestion. 275. Some animals have several Stomachs. — Some of the polypi tribes have at least four stomachs, and the aste- ria or star-fish, a very common inhabitant of our sea- shores, has ten distinct digestive organs. Fig. 71. 276. The mouth of this animal, a, is situated in a de- pression at the centre of the under surface, and leads into a capacious sack or bag, placed immediately above it, when the animal lies with the mouth downward, which What is said of the necessity of a mouth and stomach to each animal? What is said of the number of stomachs possessed by some animals ? 9 98 ANIMAL FUNCTIONS. is tlie natural position. From this central sack, there pro- ceed ten pi okmgatives, or canals, which occupy, in pairs, the centre of each ray, or division of the body, of which there are five to each star-fish. These prolongations, or stomachs, subdivide into numerous ramifications on each side, as shown by Fig. 71, c, c, which represents one ray of the asteria, laid open from the upper side. Each ray has two stomachs, such as are here shown, making ten for every animal. 277. Increased Complexity in the Stomach of the high- er Orders. — We shall not consider it necessary to describe the apparatus for digestion belonging to the different grades of animals as they ascend in the scale of organ- ization. It will be sufficient for our purpose to state, that the operations preparatory to the introduction of food into the stomach, increase in some proportion to the complexity of the animal organization. Thus the hydra takes its food into the stomach in precisely the same state that it happens to come to the mouth, and the fish, snake, frog, and many other tribes swallow their aliment in an entire state. Neither have the birds any organs for mastication, so that in common with them, they take their food in an undivided state. But the birds are furnished with an apparatus for grinding the materials thus swallowed, before they are introduced into the stomach, thus affording an example of com- plexity in the organs of nutrition, proportionate to the general scale of organic development which these ani- mals exhibit. In all the warm-blooded quadrupeds, the food is prepared by mastication and admixture with saliva, before its introduction into the stomach. With the exception of man, all animals take their food in the raw, or natural state ; but with him great preparations, and often very pernicious ones, are made to suit the ali- ment to his pampered taste, before the act of mastication commences. 278. Man eats nearly every digestible thing. — Man being an all-eating animal, there hardly exists an article which can be digested, in the sea, on the land, or in the air; lhat he has not, in some way or other, contrived to render GRINDING OF FOOD. 99 palatable, or at least to convert by the science of cookery, into something he can take into his stomach. 279. The most active ingredients in the vegetable and animal kingdoms, and even slow poisons, are in common use as condiments, for what otherwise would be whole- some food ; and notwithstanding man is the most anxious of all animals to procure long life, and is perpetually in- venting new and improved methods to prolong his earthly existence, yet in practice no animal shows so little wisdom on that very point for which he is so anxious, as the lord of creation. All the inferior animals are taught either by instinct or experience to avoid deleterious ali- ment, and to select such food as is most congenial and wholesome ; and in the wild state, most animals would starve rather than touch the food which man prepares for himself. Indeed, no being which the Creator has brought into existence, except the dog and the swine, could long exist on the scientific compounds which man has invented to gratify the artificial cravings of his omnivorous appe- tite. These animals having been, from time immemorial, subjected to human power, the one his companion, and the other the object of his cravings, have finally, like their masters, acquired indiscriminate appetites. But notwith- standing the pernicious effects of luxurious indulgence, it will be shown in another place, that man requires a va- riety of nutriment. GRINDING OF FOOD. 280. Animals which are furnished with jaws and teeth, prepare their food for the stomach by mastication. But there are several tribes which are not provided with such an apparatus, and which, as they take solid food, require some internal means of breaking it in pieces, before it enters the stomach. All the birds which live on seeds, as well as the lobster and crab, are provided with an appara- tus for this purpose. 281. The part which performs this office in the birds, is well known under the name of gizzard. That which performs the same functions in the lobster, is very differ- ent in its construction, though equally efficacious in its operations. 100 ANIMAL FUNCTIONS. 282. Grinding Apparatus of the Lobster. — This part in the lobster is represented Fig 72 by Fig. 72, which shows the inside of the stomach, together with the tritura- - ting machinery at its en- trance. There is a carti- laginous frame-work, in which the hard calcareous bodies marked a, 6, and c, are implanted. These have the form, and perform the office of teeth. The tooth, a, is situated in the middle of this frame ; it has a conical rounded shape, and is small- er than the others, b and c, are of the same size and shape. 283. When these three teeth are brought together by the action of the surrounding muscles, they exactly fit into each other, and are capable by the motion which is given them, of completely pulverizing the small shells of mollus- ca, which have been introduced into the cavity of the stomach as food. 284. Grinding Apparatus of Birds. — But the internal machinery for grinding is larger, and more completely formed in the granivorous, or grain-eating birds, than in any other animal. In carnivorous birds, as the owl and eagle, this part is entirely wanting ; but is found in all the tribes which live on the seeds of vegetables, as the hen, goose, pigeon, swan, &c. In proper with the ancient no- tion, that " every part helps a part," the grinding faces of the gizzard are dried, ground, and taken to help digestion to this day. 285. This organ, called the gizzard, has, in its structure and mode of action, some analogy to the corn-mill. It consists of two powerful muscles of a hemispherical shape, with their flat sides applied to each other, and their edges united by a strong tendon which leaves an oval, vacant Describe the triturating machine in the stomach of the lobster. Wha tribes of birds are furnished with gizzards ? GRINDING OF FOOD. space between their surfaces This mechanism is shown by , fHHf Fig. 73, which represents the gizzard of a swan laid open so as to display the two grinding faces g. These surfaces are covered with a dense horny substance, which, when brought together, and made to move backward and forward, are capable of crushing the hardest! seeds, and of reducing them to' powder. To assist in this oper- ation, many birds swallow small stones, whicli mixing with the grain facilitate the process. 286. In most birds with gizzards, there is a part called the crop, represented and laid open and empty at c, in which the food is collected and softened by heat and moist- ure before it enters the gizzard. This part, therefore, acts as the hopper to the mill, and from it only a few grains are admitted at a time, as they are ground, and pass on to the digestive organ or proper stomach. 287. The gizzards of birds have been the subject of nu- merous and elaborate experiments, by various physiolo- gists. Those of Spallanzani were the best conducted, and are the most celebrated. He introduced balls of glass into the gizzard of a turkey, and found that they were ground to powder. Tin tubes were also flattened and bent into various shapes by the powerful action of its muscles ; and even the points of needles and lancets, set in balls of lead, were worn, or broken off, while the grinding part itself appears to have suffered not the least injury. 288. These results at the time they were made and published, struck all philosophers with wonder and amaze- ment, and calculations were soberly made in order to esti- mate the actual power required in the muscles of the gizzard to perform such feats. 289. But the celebrated John Hunter having instituted further inquiries, found that the pressure of the two faces, 4 102 ANIMAL FUNCTIONS. instead of being perpendicular, as was supposed, is lateral, and at the same time somewhat circular, so that th«. power it exerts, though immensely great, is directed nearly in the plane of the grinding surfaces, and thus that the sharp edges and points were bent or broken by a grinding motion and not by direct force. 290. But this does not account for some of the results observed in the appearance of the sharp points, which were worn off, as if rubbed on a stone. This effect was at first attributed to the acrid c r solvent juices of the organ ; but, as was afterward proved, is really the effect of the pebbles which are always found in the gizzards of birds, when they can be obtained. No doubt now exists among naturalists, but that these pebbles are absolutely necessary to the perfect digestion of the food, the action of the giz- zard alone being insufficient to reduce its contents to the proper state for that process. 291. After the food has been prepared by the gizzard, it passes on to the stomach, where, by a process to be here- after described, digestion and assimilation are performed. ORGANS OF NUTRITION AND VITALITY IN THE MAMMALIA. 292. The mammalia include the highest orders of or- ganic development in the animal kingdom, embracing, as the term signifies, all such animals as nurse their young, as the human species, the quadrupeds, quadrumanna or monkey, and whale. 293. The animals are provided w^ith a complication of organs, all of which are more or less subservient to the process of digestion, for without this process none of the other functions could long be sustained. The heart and arteries wrould in a short time cease to act, unless they were supplied with blood, and the blood being formed of chyle, would cease to be produced, if the process of digestion, by which the chyle is elaborated, should be suspended or destroyed. With the cessation of arterial action, the functions of the brain and nerves would fail, and thus life itself would become extinct. What a..,mals does the class mammalia include? What other functions depend on that of digestion? If the action of the heart and brain should cease, how would digestion be effected ? What is said of the dependance of these functions on each other? ORGANS OF THE MAMMALIA. 103 And so in its turn, the process of digestion would cease with the want of action in the heart and brain, so that all these functions are performed, as it were, in a circle, each one being dependant on the other. In one view, each of these functions may be considered as subservient to the other, while in another view, each is seen to be entirely dependant on the other. 294. Plan of the most important Viscera. — A connect- ed view of the most important visceral, and vital organs, are represented by Fig, 74. This is a side view, showing Fig. 74. the natural situation of the parts, as they are placed in quadrupeds, but may be considered as applying to the hu- man species without any material change. 295. In the explanation of this view we will begin with the passage of the food to the stomach. The esophagus, o, is a muscular tube leading from the mouth to the stomach, and through which the food passes to the latter organ. Of the stomach, s c, is the part nearest the heart, and is called the cardia, or cardiac portion, while the opposite part is termed pylorus. This leads to the intestinal tube marked i, i. The mesentery, in, connects the latter part with the back ; the use of which will be explained directly. The enlargement, r, is the receptacle of the chyle , and from 104 ANIMAf. FUNCTIONS. which tnere proceeds a tube called the thoracic duct, which conveys the chyle to the circulation ; /, is a portion of the liver. That portion of the heart, h, which is marked u, is called the auricle, while the cavity, h, is called the ventricle, a is the aorta, which is the trunk of the largest artery, and v, v, v, are the large veins which convey the blood to the heart. The part b, is a portion of the lungs. 296. Having pointed out the different parts, we will next explain in few words, the different processes by which food is changed iilto blood, and also the course of the blood in its circulation. 297. The food being masticated and mixed with the fluid secretions of the mouth, is then collected into a mass by the muscles of the cheeks and tongue, and swal- lowed, being carried along the tube o, by its contractions, down to the stomach s. There it is mixed with a fluid secretion of the stomach, called the gastric juice, and by which it is dissolved and prepared to afford -chyle after it has been conducted through the pylorus. After having passed the pylorus p, the food is mixed with the bile, a bitter secretion from the liver, and also with a fluid from the pancreas, when a portion is elaborated into chyle, and is ready for absorption into ihe-lacteals, which are the ves- sels spread over the mesentery, like a net-work, as shown by the figure. 298. The chyle being taken up by the lacteals, the mouths of which are thickly spread over the interior of the intestinal tube, is carried by many branches to the recep- tacle of the chyje, r, from which it is conveyed by the thoracic . duct, t, to one of the large veins under the arm, called the subclavian vein, and by this vein to the heart. It thus gains admittance to the general circulation of the blood, and by a process which we cannot explain becomes blood itself. 299. It is by means of a constant reception of chyle into the circulation, that the quantity of blood continues undiminished ; and that the arteries are enabled to furnish Explain Fig. 74, and point out the name and situation of each part, as designated by the letters. In what part of the system is the chyle thrown into the circulation ? ORGANS OF THE MAMMALIA. 105 glands in all parts of the system, with the "purple fluid from which all the various secretions are produced. By these processes, vegetable as well as animal matter, is converted into flesh. 300. It is through the routine we have described, from the mouth to the subclavian vein, that the system is reno- vated, and the exhaustion consequent upon the exercise of all its numerous functions, is constantly repaired, and the whole system kept in vigor and health. Not a particle of nourishment can be added to the circulation until the food has been changed into chyle ; nor is there any other organ by which the chyle can be conveyed to the blood, except the thoracic duct ; hence our lives constantly depend on a little stream of chyle, about the size of a crow-quill, which enters a vein under the arm-pit. With- out this source of renovation, the mass of blood would soon become deficient in quantity and quality ; there would be no remedy for exhaustion, no source of muscu- lar power, and we should soon fall away and die of inan- ition, without the hope of a remedy. 301. Circulation of the Blood. — The blood is brought from all parts of the system by the veins, which are con- stantly enlarging by communications with each other, as they approach the heart. The veins v, v, Fig. 74, are called the ascending and descending vence cavce. These convey the blood to the right auricle of the heart, u. When the auricle is full, it contracts, and sends the blood to the right ventricle h. From the right ventricle, it is thrown by the strong contraction of the heart, to the lungs, where it is exposed to the influence of the atmo- sphere. It is then brought to the left auricle of the heart, which contracting, throws it into the left ventricle, the action of which forces it through the aorta, to all parts of the system, to be returned again to the right auricle by the veins, as before. 302. This, however, is only a general account of the circulation ; a more particular one being reserved, until we come to treat of the circulation in different orders of animals. What is said of the importance of the chyle to the living system? 106 ANIMAI, FUNCTIONS. MASTICATION. 303. This word comes from the Latin mastico, which signifies to chew. Chewing is one of the natural functions of animals, the object of which is to divide the food into minute pieces, and thus to prepare it for passing through the esophagus into the stomach, to undergo the process of digestion. 304. While the food is masticating, it is at the same time intermixing with a fluid called saliva, which is pre- pared by glands situated around the mouth, and into the cavity of which it is poured through small ducts, coming from the glands by which it is secreted. The action of the muscles concerned in mastication, serve to stimulate these glands; in consequence of which they afford a larger quantity of the fluid at the time when it is most necessary. The same action also facilitates the passage of the saliva into the mouth. 305. If the mouth had been constructed without this provision for moistening the food, it is obvious that dry, absorbent substances could not have been swallowed ; since it is absolutely necessary, as our experience teaches, to reduce such substances to a soft pulpy mass, before they can be forced through the esophagus. 306. There is a great difference in the form, structure, position, and number of the teeth of different animals ; all of which bear a direct and intimate relation to the kind of food on which they subsist. Thus the teeth of the lion, the wolf, and the cat, are constructed for tearing the flesh of animals ; while those of the cow, sheep, and deer, are made to crop the tender herbs. 307. The teeth of the lion could no better perform the office assigned to those of the cow, than the cow could rend the skin, and divide the muscles of a living victim, in the manner of the lion. 308. Teeth of Man. — In the human subject the number What is meant by mastication ? Is chewing, a vital, or a natural func- tion? What is the use of mastication? How is the food moistened dur- ing mastication? What is said of the form of the teeth, in relation to the kind of food on which the animal lives ? MASTICATION. 107 of teeth is thirty-two, the shapes and names of which it is proper here to present to the student. Fig. 75. s of the muscles generally derived from? 216 MENTAL AND PHYSICAL EXERCISE. 672. The action of the Muscles depend upon the Brain. — We have said that the muscles have the power of con- traction and .relaxation, at the will of the animal. We can by no means trace the connexion between the action of the brain in willing, and the action of the muscle in contracting. We know that if all nervous communication between the brain and muscle be cut off, there will no effect be produced by the action of the brain ; that is, we may will to raise the arm, but the muscles remain inac- tive, without the intervention of the nerves. This proves that the nerves in some way, transmit to the muscles the mandate of the brain ; but how this is done, is a mystery which has never been solved, and most probably will always remain beyond the limits of human knowl- edge. 673. Muscular Contraction. — When a muscle con- tracts, the swell becomes enlarged or thickened, and the two ends approach each other. By grasping the thick part of the arm, above the elbow, and bringing the hand toward the mouth, the bulk of the part grasped, will be felt to enlarge, and grow hard, as though it actually con- tained more matter than before the contraction. 674. In this act, the absolute bulk of the muscle is, however, supposed not to change, though its shape is con- siderably modified, a part of the bulk toward the extremi- ties, being thrown into the centre, hence the increased hardness, and swelling of this part. The contraction of the muscle appears to consist in the shortening of all the fibres individually, by which the whole bundle is diminished in length. On the contrary, relaxation appears to be simply the want of contraction, or a passive state in which the muscle ceases to act. 675. Daring sleep, all the muscles are in a relaxed and passive state, but when awake, we can take no position, except the recumbent one, in which, more or less of these organs are not in an active state. In the standing pos- Can we trace any connexion between the action of the brain in swelling, and the action of the muscle in contracting? When a muscle contracts how is its shape altered ? In what does the contraction of a muscle con sist ? In what does relaxation consist ? THE MUSCLES. 217 ture the muscles of the lower limbs and back are perpetu- ally active, in order to keep the upright position ; for the instant they are relaxed, as from faintness or a fit, we fall to the ground. 676. Use of the Muscles.-* -Some of the uses of the muscles are obvious, from what has just been said. They are also the grand organs of motion, by which the system is moved from one place to another, constituting the instru- ments of locomotion. It is by the muscles, indeed, that all the motions of the body, whether general or local, are performed ; not a finger moves ever so slightly without the contraction of some fibres ; nor is a word ' spoken, or any sound of the voice heard, without a similar motion of the muscles. Even the act of respiration is carried on by these moving powers, and therefore life cannot be sustain- ed, even for a moment, without their action. 677. Mechanism of the Muscles. — In the muscles con- cerned in locomotion, and in the other voluntary motions of the body, the rise or origin of the muscle is from one bone, and the insertion into another, the thick part being between these two points, and the motion is performed by the intervention of a joint. 678. The bones must, therefore, be considered as levers, acted upon by the muscles ; the part where the tendon is inserted, representing the power ; the joint itself the fulcruiL, and the part that is moved constituting the weight. 679. Lexers are divided into three kinds, according 'to Ih' relative position of their three essential parts, the weight, the power, and the fulcrum. In the first kind the fulcrum is between the weight and the power, or moving cause ; in the second, the fulcrum is at the end of the lever, the weight being between it and the power ; in the third, the power is in the centre, between the weight and fulcrum. When are all the muscles relaxed ? What are the uses of the muscles ? Considering the bones and muscles in a mechanical relation, what part is the lever? What part the power? What the fulcrum? What the weight ? How do the three kinds of levers differ from each other? 19 218 MENTAL AND PHYSICAL EXERCISE. 680. So far as mechanical advantage is concerned, the last is by far the less effective, and it is the application of this principle by which the levers are moved by the mus- cles. We shall see, however, that it is not mechanical power alone which is wanted in the construction of the limbs, and that all the circumstances considered, this is the only kind of lever which could be employed consistently with the perfection of our organs of motion 681. Muscular action of the Jlrm and Hand. — The motion of the forearm may be taken as an example of the effect of muscular contraction, and the manner in which it is produced in the animal system. When we raise a weight by bending the elbow joint, this is effected by mus- cles situated below the shoulder, with the tendons inserted into the upper sides of the bones of the forearm just below the joint." 682. Let a b, Fig. 122, represent the bones of the fore- arm, b d the bone of the arm, d the muscle, e the tendon, Fig. 122. c the insertion of the tendon into the radius, and b the elbow joint. It is plain that the contraction of the muscle makes c approach towards d, which, as d is a fixed point, is effected by bending the joint 6, raising up the point c, and thus giving great velocity of motion to a, and the weight attached to it. 683. " The consideration of the manner in which the muscle acts in this case, proves that the mechanism of the animal body is calculated to produce a great loss of abso- lute power. It is an established position in mechan- ics, that in the action of levers, the power is to the weight as the distance between the weight and the ful- • What and is applicable to the bones ? Explain Fig. 122, and show why much mechanical force is lost in that arrangement. Why is muscular power thus sacrificed? THE MUSCLES. 219 crum, is to the distance between the power and fulcrum. In the present case, therefore, the power of the muscle is to the effect produced by it, as a b, is to c b ; and sup- posing c 6, to be one twentieth of the length of a b, then one twentieth only of the power of the muscle is exerted in raising the weight, the rest being expanded in acting against the disadvantage of the position."* 684. We shall however, find that it is a general fact, or law of the animal economy, that muscular power is always sacrificed to convenience. Had the object been to raise the weight with the least possible power, the muscle would have been placed on the fore-arm, and the tendon inserted into the lower part of the arm-bone, but in this case the awkwardness of the limb would have much more than counterbalanced the supposed advantage of saving the muscular power. This remark applies with still greater force to the fingers, which are now moved by the contraction of muscles placed on the fore-arm, and from which small delicate tendons proceed along both sides of the hand, to be inserted into the several ranks of bones. Now had this order been reversed, and the muscles placed on the fingers, by which the greatest mechanical advantage would have been gained, the con- sequences would have been, a hand so clumsy as to have been nearly useless, and not only so, it would have been, when compared with its present delicate and beautiful form, an absolute deformity. 685. Motions of the Radius and Ulna. — Beside the leverage motions of the fore-arm above described, the two bones composing it, called the radius and ulna, have movements peculiar to themselves. 686. In Fig. 123, a is the radius, and 6 the ulna, both of which are articulated to the humerus, as formerly shown in Fig. 65. Suppose the muscle of the hand had been so placed as to have given that organ the greatest mechanical power, what would have been the result in its form and usefulness ? * Bostock's Physiology, vol. i, p. 186. 220 MENTAL AND PHYSICAL EXERCISE. Fig. 123. 687. The easy motions of the hand, which might be supposed to belong to the wrist, are in a great proportion owing to the motions of the radius and ulna. The up- and-down action of the hand, when the lower ends of these bones are still, belong to the wrist, which is com- posed of eight bones; but the rolling motions of the hand, by which the palm is alternately turned up and down, are caused entirely by the slight movements of the radius on the ulna. The 'ulna projects beyond the head of the humerus, forming, when the arm is bent, the point of the elbow. The radius has a small round When the palm is turned up and down, what bones are concerned in the motion ? THE MUSCLES. 221 head on which it turns, without any motion of the humer- us ; and as the bones of the wrist are attached to the lower end of this bone alone, and not to the ulna, c, when the radhis revolves, the whole hand turns with it. The alternate rolling motion is called pronation and supi- nation. 688. Motions of the Fingers. — The motions of the fingers do not merely result from the actions of the large muscles, which lie on the forearm, these being concerned more especially in the stronger actions of the hand. 689. The finer and more delicate motions of the fingers are performed by small muscles, situated in the palm and between the bones of the hand, and by which the fingers are expanded, and moved in all directions with wonderful quickness. 690. These are the organs which give the hand the power of performing all its nicest motions, and by which we are enabled to execute our finest works ; such as en- graving, writing, sewing, and painting ; in all these cases- the motions are directed by the will, while the instrument is guided by the eye. 691. The Thumb. — The thumb is the antagonist to the fingers. On the length, strength, free lateral motion, and perfect mobility of the thumb, depends the power of the human hand. Without the fleshy ball of the thumb the power of the fingers would avail nothing ; and according- ly, the large ball, formed by the muscles of the thumb, is the distinguishing character of the human hand, and espe- cially that an of an expert workman.* 692. The Fingers of different Lengths. — Although the fingers are of different lengths, yet when they are doubled into the palm, their ends become parallel. This is owing to their difference of length being chiefly in the first rank To what bone is the wrist attached ? By what organs are the finer and more delicate motions of the hand performed ? What is said of the im- portance of the thumb to the perfection of the hand ? • Bell, on the Hand. 19* 222 MENTAL AND PHYSICAL EXERCISE. of bones ; in consequence of which, the middle joint is carried a proportionate distance from the palm, so that in doubling each point comes to the same line. 693. This difference in the length of the fingers, though we are seldom aware of it, serves to adapt the hand to a great variety of uses, which would have been awkwardly performed had they all been of the same length. In writing, for instance, did the little finger project an inch and a half beyond its present place, how awkwardly should we perform. In grasping any small article with the whole hand, a similar awkwardness and difficulty would be experienced. 694. " Nothing," says Sir Charles Bell, " is more re- markable, as forming a part of the prospective design to prepare an instrument fitted for the various uses of the human hand, than the manner in which the delicate and moving apparatus of the palm and fingers is guarded. The power with which the hand grasps, as when a sailor lays hold to raise his body in the rigging, would be too . great for the texture of mere tendons, nerves, and vessels ', they would be crushed, were not every part that bears the pressure defended with a cushion of fat, as elastic as that which we have described in the foot of the horse and camel. To add to this purely passive defence, there is a muscle which runs across the palm, and more especially supports the cushion on its inner edge. It is this muscle, which, raising the edge of the palm, adapts it to lave water, forming the cup of Diogenes." Thus does anato- my prove that the human hand was designed for laborious employments. 695. Says Ray, " Some animals have horns, some have hoofs, some teeth, some talons, some claws, some spurs, and beaks ; — man hath none of all these, but is weak and feeble, and sent unarmed into the world — but a hand, with reason to use it, supplies the place of all these." 696. Thus we see that the " lord of creation," through What is said of the different lengths of the fingers in making the hand a perfect instrument ? What prevents the nerves and tendons fro m injm y when we grasp firm a hard body, as when a sailor climbs a rope. MUSCULAR AND NERVOUS SYSTEMS. 223 the special beneficence of his divine Maker, has not only been endowed with the attributes of reason, judgment, and discretion, but has also been given the most perfect of all mechanical instruments, by which to carry into effect the plans which his intellect might suggest. No created being, except man, can, with any instrument furnished him by nature, do so much as to draw a pair of parallel lines, or even a single straight line. But man, by the exercise of his reason, assisted by his hands, builds palaces, erects monuments, constructs ships, and with the same instru- ments manufactures watches ; and with still more delicate touches, imitates Nature herself with such art, as almost to appear the author of a new creation. 697. All these powers, so far from fostering the pride and self-sufficiency of man, ought to be a reason why he should render to the Giver of such endowments, perpetual obedience, thanksgiving, and praise. CONNEXION BETWEEN THE NERVOUS AND MUSCULAR SYSTEMS. 698. Every person of common observation, has noticed the great difference which exists in the human species, with respect to muscular firmness and strength, and ner- vous irritability and weakness of the bodily powers. Some persons are strong and vigorous in their muscles, and are capable of exerting a great degree of strength, and of continuing it for a long period ; while others, perhaps of equal size and weight, are absolutely incapable of putting forth such bodily powers, or can do so but for a moment, when they become utterly exhausted. 699. We find that persons of great muscular firmness are not generally subject to what is called " nervous ex- citement." They are not easily thrown into trepidation ; they keep cool and quiet on all occasions ; while those with the lax muscular fibre are easily thrown into excite- ment, any sudden event being sufficient to bring on gen- eral agitation, or even convulsions of the whole system. What is said of the goodness of the Creator in providing man with an niment to execute the projects his reason might suggest? 224 MENTAL AND PHYSICAL EXERCISE. 700. The Miiscles furnished with two Sets of Nerves.— The cause of such differences in the temperaments, dispo- sitions, and muscular powers of these two classes of indi- viduals, as above described, appear to be accounted for by a comparatively recent discovery of Sir Charles Bell, who has found "that the muscles are furnished with two sets of nerves, one set being chiefly concerned in muscular motion and the other in sensation. 701. In the seventh edition of his Anatomy, Sir Charles gives the following explanation of the uses of these two kinds of nerves : — 702. " The muscles," says he, " have two nerves, which fact has not hitherto been noticed, because they are com- monly bound up together. But whenever the nerves, as about the head, go in a separate course, we find that there is a sensitive nerve and a motor for moving] nerve dis- tributed to the muscular fibre, and we have reason to conclude that those branches of the spinal nerves which go to the muscles, consist of a motor, and a sensitive fila- ment. 703. " It has been supposed hitherto, that the office of a muscular nerve is only to carry out the mandate of the will, and to excite the muscle to action ; but this betrays a very inaccurate knowledge of the action of the mus- cular system; for before the muscular system can be controlled under the influence of the will, there must be a consciousness, or knowledge of the condition of the muscle. 704. " When we admit that the various conditions of the muscle must be estimated, or perceived, in order to be under the due control of the will, the natural question arises, is that nerve which carries out the mandate of the will, capable of conveying, at the same moment, an im- pression retrograde to the course of that influence which is going from the brain to the muscle ? If we had no facts in anatomy to proceed upon, still reason would de- clare to us, that the same filament of a nerve could not convey a motion, of whatever nature that motion may be, whether vibration, or motion of spirits, in opposite direc- tions at the same moment of time. MUSCULAR AND NERVOUS SYSTEMS. 225 705. " I find that to the full operation of the muscular power, two distinct filaments of nerves are necessary, and that a circle is established between the sensorium and the muscle ; that one filament or single nerve carries the in- fluence of the will toward the muscle, which nerve has no power to convey an impression backward to the brain ; and that another nerve connects the muscle with the brain, and, acting as a sentient-nerve, conveys the impression of the condition of the muscle to the mind, but has no operation in a direction outward from the brain toward the muscle, and does not therefore excite the mus- cle, however irritated." 706. Thus we are, it would seem, furnished with a double apparatus, by means of distinct nervous filaments, one for muscular action and the other for sensation, — the one to carry our commands from the brain to any mus- cle which we would* have contract, and the other to bring back an account of the condition of said muscle, and inform us whether the contraction is too great or too little, or whether the direction of the lever which the muscle has been concerned in moving is precisely such as to answer the purpose intended. Thus as the painter goes on with his work, these sentient-nerves con- stantly warn him precisely how much muscular move- ment is required in his hand to place his colors according to his taste; while the nerves of contraction move the muscles exactly as the will directs them, and as these different kinds of information are conveyed from and to the brain in an instant, or " as quick as thought," so we are insensible of the lapse of the least portion of time between the mandate from the brain and the action of the muscles. 707. The same process takes place in every action which we perform. When we direct our eyes toward a land- scape, for instance, and having examined one group of objects, move them ever so little toward the next, this is not done without the action of the sentient-nerves, which inform the brain exactly of the situation of the muscles of the eyes; which muscles, in their turn, are directed how to move the orbits. Thus, if we wish to turn the eye from right to left, or upward, or down- 226 MENTAL AND PHYSICAL EXERCISE. ward, or alternately in all these directions, the straight- muscles (Fig. 104), are thrown into alternate contrac- tion and relaxation, at the mandate of the brain. Mean*- time the visual portion of the eye furnishes us with a picture of the landscape, the different parts of which we thus examine, by means of the mechanical portion. Is it not plain that infinite wisdom and Almighty power only, could have devised and constructed such machinery as this ? 708. Personal Temperament and Disposition accounted for. — It is on the same principles that we can account for the difference which we observe in persons with respect to their temperaments or dispositions, as already stated. When we see a person of feeble muscular powrers easily thrown into agitation, turning pale, or fainting by slight causes, and morbidly sensitive to every nervous impres- sion, we may conclude that in such persons the sentient- nervous system predominates ; or, in other terms, that the nerves which carry impressions to the brain, are either more highly developed, or are in a more sensitive state than those concerned in muscular contraction. In such persons, the flesh is commonly soft to the touch, and has a pallid hue. On the contrary, in persons where there is great muscular power, as indicated, not only by the strong outlines of the muscles themselves, but also by the capability of enduring great and continued bodily exertions, and by a temperament void of excessive sensibility, being able to bear strong nervous impressions with little indication of nervous feeling; we may con- clude that in such persons the motor-nerves, or those concerned in muscular contraction, predominate over those subservient to sensation. In such persons, the muscles are commonly rigid to the touch, even when relaxed, presenting a striking contrast with the morbid softness of those parts, in persons of excessive nervous mobility. 709. Natural Disposition may be modified. — Although, as we have supposed, and the fact cannot be doubted, that there is a natural difference in different persons, with respect to the distribution of the sentient and muscular MUSCULAR AND NERVOUS SYSTEMS. 227 nerves, still it is also true, that the resulting dispositions can be modified, and in a great measure controlled by ex- ternal circumstances. 710. In persons where the two different nervous powers are naturally in the most perfect equilibrium, the one may be made to predominate completely over the other, by the habits, the occupation, or perhaps the condition in life into which the person happens to be thrown. Excessive study, a sedentary life, luxurious -living, especially in re- spect to drinks, habitual melancholy, or a general dispo- sition to give way to the love of ease and indolence, will, either of them, in a longer or shorter time, induce a nerv- ous temperament, though the natural organization of the two systems might have been as perfect as ever a human being enjoyed. 711. On the contrary, persons in whom the nervous disposition might have naturally inclined to laxity of mus- cular fibre, and excessive sensorial irritability, by the ha- bitual practice of rigid temperance, moderate study, if at all, an active life, requiring the constant use of the mus- cles, together with a train of circumstances in life calcu- lated to inspire cheerfulness and hope — by these means, such persons would undoubtedly overcome the natural predominance of the nervous system, and induce a perma- nent state of muscular firmness, which would produce a highly gratifying contrast with that which an apposite mode of living, or train of circumstances would have pro- duced. 712. Force of Muscular Contraction. — The force with which the muscles contract, depend on the size and condi- tion of the muscle, and on the energy of the brain ; that is, the degree of excitement which exists during the time. 713. The same muscle, or same limb, varies greatly in the strength which it is capable of exerting. If a man naturally and habitually powerful in his muscles, should suffer them to remain inactive for a considerable length of time, they will become absolutely incapable of those strong contractions, which, had they been habituated to constant action, they would have performed with ease. This is a fact that has fallen within the experience of almost every 228 MENTAL AND PHYSICAL EXERCISE. person, and is accounted for in the popular way, by the common observation, that " if we do not employ our muscles, they will lose their strength/' which indeed ac- counts for the fact, but not for its cause. The cause ap- pears to be, that the action of a muscular part, excites the blood-vessels to throw into it a greater portion of their contents than they otherwise would, so that such parts are better nourished than those that remain inactive. Thus the arm with which a blacksmith uses his hammer, whether the right or left, is by far more powerful than the other. The muscles of this limb are also larger than those of the other, and are much more tense and rigid to the touch — a positive proof of the tendency of muscular motion to pro- duce strength and vigor. 714. The Roman gladiators understood, practically, the great advantages of employing their muscles, in order to gain the most perfect use of their limbs, together with the utmost physical power. Hence they put forth continued exertions in walking and other exercises, and performed feats of strength, which, in the present age, would appear incredible. 715. In more modern times, men have occasionally ap- peared, who, from the size and condition of their muscles, were capable of exerting degrees of strength w7hich as- tonished every beholder. Sir David Brewster, in his " Natural Magic," has collected and stated a number of instances of this kind. 716. Thomas Topham. — One of the most powerful men of modern times, was the famous Thomas Topham, of whom many ludicrous anecdotes, illustrative of his enor- mous muscular. strength; are related; such as the rolling up of pewter dishes with his hands, as others tip sheets of pasteboard ; crushing the bowls of tobacco-pipes, by the lateral pressure of the fingers of one hand, &c. He took an iron kitchen-poker, .a yard long and three inches in circumference, or an inch in diameter, and holding it in his right hand, struck it upon his bare left arm, be- tween the elbow and the wrist, until he bent the iron nearly to right angles. He took another poker, and holding the ends of it in his hands, put the middle over his neck, and then brought the two ends together before MUSCULAR AND iNKKVOUS SYSTEM. 229 him; and afterward undid the mischief, by making it straight again with his hands, as others do a piece of wire. He lifted a stone weighing 800 pounds, with his hands only, standing in a frame above it and taking hold of a chain to which it was fastened. 717. These feats illustrate the force of muscular contrac- tion, depending merely on size and condition ; since in such cases there is no uncommon nervous excitement, or cerebral energy. But where there is strong mental ex- citement, as in mania, or delirium, the other circumstances being equal, there is a still greater exhibition of muscular power, as the keepers of retreats for the insane have often found to their sorrow, and sometimes to their horror and dismay. 718. No one, except by experience, can have the least conception of the efforts of muscularity, which a deli- cate and slightly-made female is capable of exerting when in a state of maniacal rage. In some instances, men of ordinary physical powers, are mere " smoking flax," before the muscular velocity of these most pitiable objects ; and even the strongest men are sometimes foiled in attempting to prevent them from committing some outrageous act on which they are determined. 719. Such acts are rather the effects of muscular veloci- ty, than of strength ; for the efforts are soon exhausted, after the limbs are brought into a situation where a quick movement is no longer of any avail. 720. Method of increasing the Muscular Powers. — There is no doubt the power of the muscles may be greatly increased by a certain restricted course of exercise and diet, to which the subject confines himself for a given length of time. The English boxers go through such^a course in order to prepare themselves for public per- formances, and we can see no reason why others should not imitate their example, so far as the training is con- cerned, in order to gain that perfect health which it is said these men enjoy. There are few, however, who would submit to such discipline without some special motive, other than the enjoyment of ordinary health. But that the reader may observe how these men deny 20 230 MENTAL AND PHYSICAL EXERCISE. themselves, for the purpose of acquiring mere musculai power, and that for no laudable purpose, we will give a few of the rules of training. 721. There are Professors of Sparring, whose sole business it is, to teach the art, by learning their pupils the manner and time of striking, as well as the modes of de- fence ; and the means of gaining muscular strength by diet and exercise. While training, they are directed to eat beef and mutton, rather under than over done, and this without any seasoning or sauce, the only addition to these two articles of solid food, being bread or biscuit. Neither veal, lamb, pork, fish, milk, butter, cheese, puddings, pastry, or vegetables of any kind are allowed. The beef and mutton must be fresh, that is, not" salted, and may be cooked by roasting, broiling., or boiling, alternately, or as best suits the appetite of the trained. 722. The strictest temperance is absolutely insisted on, by all regular trainers, good home-brewed beer, or ale, being recommended as the ordinary drink at meals. Those who do not like the beer are allowed a little red wine and water with their dinners, but not to exceed in quantity eight ounces, or half a pint per day, spirits of every kind being strictly prohibited. 723. Eight hours sleep are considered necessary, but this is left to the previous habits of the person, and may be varied according to the amount of exercise during the day. 724. The breakfast hour is eight o'clock ; dinner at two ; supper being entirely omitted, or to consist of a little bit of cold meat at eight ; after which a walk is taken, and they retire to bed at ten. 725. Much exercise, consisting of sparring and walking, is taken during the whole time of training, and undoubtedly *]* high degree of cheerfulness in which men thus situated indulge, contributes greatly to the good effects of the com- parative temperance to which they are restricted, at least for a considerable time. 726. Dr. Kitchener says, that " by this mode of proceed- ing for two or three months, the constitution of the human frame is greatly improved, and" the courage proportion- ably increased. A person who was breathless, and pant- ing on the least exertion, and had a certain share of those nervous and bilious complaints, which are occa- PRACTICAL INFERENCES. 231 sionally the companions of all who reside in great cities, by such means becomes enabled to run with ease and fleetness." 727. " The restorative process having proceeded with healthful regularity, every part of the constitution is ef- fectually invigorated, and a man feels so conscious of the augmentation of his powers, both bodily and mental, that he will undertake with alacrity a task which before he could not but shrink from encountering." 728. About two months is considered the average time necessary to fit a man for the ring, or for public exhibi- tion as a boxer by the above means ; and it is particularly worthy of observation, that alcoholic liquors are discarded by these men, for no other reason than that experience has taught them, that its effects are to weaken the muscular powers and deotroy the courage of their pupils. Therefore, he who has much labor to perform, or a battle to fight, ought never to drink spirits. PRACTICAL INFERENCES FROM THE FOREGOING PRINCIPLES. 729. Connexion between the Brain and the Muscles. — The intimate connexion which exists between the muscles and the brain — between the nervous system generally, and those parts by wThich the motions of the human frame are produced, and which connexion has been illustrated by a reference to the voluntary muscles — indicate in a most de- cided manner the mutual dependance which subsists be- tween them ; and tend to show as clearly as the nature of the case will admit, the necessity of employing both the nervous and muscular functions at the same time, in order that both should be in a healthy state. And especially do these principles show, that the nervous system cannot long be employed alone without a derangement in the functions of both. 730. It has been our chief object in the foregoing sec- tions, to show the connexion which exists between the nervous system and the voluntary muscles, but this may be taken as an example of the existence of the same relation between that system and all the muscular fibres in the 232 MENTAL AND PHYSICAL EXERCISE. body whether voluntary or not. Thus the heart, and the muscles of respiration, are equally, with the voluntary muscles, dependant on the action of the brain. The or- gans of mastication and digestion are also under the same influence. 731. In every series of actions, therefore, which take place in any part of the whole system, there is a mutual sympathy and dependance on some other part. MUSCULAR EXERCISES OF THE CLERGY AND OTHER LITERARY MEN. 732. And now we come to the more especial object of this part of our work, which is, to show that the vigorous functions of the brain cannot long be sustained, without a corresponding exertion of the muscles, and that this exer- tion absolutely requires that the brain should be more or less excited. We intend that these doctrines should apply more particularly to students and literary men, and we shall begin by showing the duty of ministers of the gos- pel in respect to bodily exercise. The present condition of the clergy and other literary men of our country, points to the vast importance of seeking some remedy against the consequences of literary pursuits, and sedentary habits, on their corporeal and mental functions. Not only ministers of all ages, but students, only a few years advanced in their studies, are constantly "breaking down" as it is termed, under the pressure of their literary burdens; many of the first class being obliged to go to Europe, or otherwise suspend their labors in order to recruit their wTornout frames, and rest awhile from their cerebral occu- pation ; while perhaps an equal number of the last find themselves under the necessity of retiring entirely from the field of literary pursuits, and of seeking some employ- ment in which less is required of the nervous, and more of the muscular system ; and thus the literary or ministerial services of many young men of great promise, and whose labors and influence would be highly important to the church, or the interests of education, are in a great meas- ure lost to the country. MUSCULAR EXERCISE OF LITERARY MEN. 233 733. Causes of these Failures. — With respect to the causes of these calamities, for such they certainly are, both with respect to individuals and the nation, there can be only one opinion. They are brought on by too much mental and too little muscular labor. Thus the 'balance of the system, which we have seen requires a due propor- tion between the exercise of the nervous and muscular powers, is lost, — the equilibrium of health is destroyed, in consequence of the predominance of the sentient, over the muscular principle. 734. Obvious Effects of too much Mental Labor. — In such subjects, it will be found, that after a while the flesh becomes soft and flabby, while the muscles can only be made to perform their ordinary functions with difficulty, all continued or violent exercise is instinctively avoided, and even a walk of a mile or two, at the urgent request of a friend, and which once gave so much pleasure, is now undertaken with reluctance. Fatigue, even after walking but a few hundred yards, becomes the prominent feeling, and the man often returns home, after a short trial, for fear that he shall not be able to do so, if he continues his walk. Having returned, perhaps out of breath, he seats himself, and concludes that exercise, since it brings on fatigue, is not only useless, but hurtful to him ; and thus, if he cannot be made to change tins opinion, consigns himself to the nearly hopeless condition of a confirmed " literary dyspeptic." 735. "Meantime the nervous system increases in suscep- tibility in proportion as the muscles lose their contractile powers, and fall into a state of weakness. The subject becomes exceedingly sensitive to nervous impressions. Occurrences of little consequence, and which in his former condition would have produced no sensation, now affect him very unpleasantly. He becomes irritated and vexed at every little mishap in the affairs of life. His friends, he begins to imagine, do not behave toward him as for- merly ; they have deserted him in his affliction ; and his own family are wanting in that kindness which was for- merly shown him, and which his present weak condition now particularly demands. At the same time he finds it 20* 234 MENTAL AND PHYSICAL EXERCISE. exceedingly difficult for him to proceed with his literary labors. His head often feels as though there was a rush of blood upon the brain ; his intellect becomes clouded, and he cannot keep along with the thread of his subject, or pursue his studies, as formerly. Sometimes he throws down his pen in utter despair, and thinks he would wil- lingly change places with any laborer he happens to see in the street. 736. These are but a few of the feelings, and troubles, and perplexities, which a student suffers, when he allows his nervous, to gain the .ascendency over his muscular sys- tem, and unless some remedy be sought, will most proba- bly end in palsy or apoplexy, or, at least, in such a con- dition of the system as to render it incapable of any useful employment for a length of time, depending more or less on that, during which it has remained in such a condition. 737. Clergymen not allowed exciting Exercise. — The cause of these affections we have said, is an undue pro- portion of mental labor, when compared with that of muscular exercise. 738. With respect to clergymen, it is well known that there exists an artificial difficulty in their indulging in that kind of exercise which is most congenial to mental and muscular vigor, owing to the habits and opinions of soci- ety. For it is the law of the system, which applies to ministers equally with others, that no exercise is effectual in restoring, or maintaining, the equilibrium between the nervous and muscular systems, unless the brain is at the same time excited. By this we mean, that the exercise must be of that kind in which the mind, for the time, takes a strong interest. This is absolutely necessary, nor is it, we believe, possible, for any one who has lost his muscu- lar energy by studious and sedentary habits, to regain it by any kind of exercise which does not give pleasure, or, to use a more common phrase, " carry the mind along with it." 739. Nor is it in the power of students generally, to retain their vigor of mind and body, for any considerable length of time, without the use of some such exercise. 740. The principles we have already drawn, from the fact MUSCULAR EXERCISE OF LITERARY MEN. 235 that every muscle has distributed to it, one set of nerves for muscular action, and another for cerebral impressions, proves beyond all doubt, that this is the case. The vigor- ous and healthy action of the muscles absolutely require that the brain, at the same time, should be under excite- ment, otherwise the nervous influence from which muscular contractility is derived, will not be supplied. 741. Now the great obstacle to clerical amusements appears to arise from the circumstance, that the feelings and prejudices, of the public, to a considerable extent at least, will not allow these men to partake of such gym- nastic sports as people generally may indulge in, and which, of all others, is the kind of exercise they most require. 742. We are far from desiring to see the dignity of the clergy lowered, and we should regret as much as others, to see them doing acts which would in the least degree tend to lessen the respect \vhich they have, and ought to maintain from the public. But It seems absolutely necessary that something should be done on this subject. Not a year elapses, but a number, often of the most de- voted and useful members of the sacred office, in different parts of our country, are under the necessity of leav- ing their people, being literally " worn out" with their clerical labors. This, it is well known, is the case, in a greater or less degree, with all the orthodox denomina- tions, the ministers of which, are expectgd every Sabbath in the year, at least in many parts of the country, to pro- di%e two well-written sermons, beside a semi-weekly lecture; and to perform other parish duties, requiring as a whole, almost unremitted mental labor from one year's end to another. 743. Men incapable of constant Mental Labor. — Now the facts clearly prove that human beings, taken as a body, are incapable, under such circumstances, of sustaining such mental burdens ; they sink down under them from debility and exhaustion, and one after another, even in the prime of life, and in the midst of their usefulness, disappear from public scenes, and in not a few instances, find that they have done so too late. 744. Clergymen are still men, and like others, are sub- iect to the laws which govern vital and corporeal action ; 236 MENTAL AND PHYSICAL EXERCISE. and it is therefore, plain, either that the public must dis- pense with a portion of their services, or that they must be allowed to indulge in recreative exercises ; otherwise they will inevitably sink under their mental labors, and many of them at least, go down to premature graves. 745. Former Condition of the Clergy. — The condition of the clergy in this country, is entirely different from what it was within the memory of many of them, who are still able to perform their clerical duties ; and who have lived to see several generations of their younger brethren come forward, and pass away, while they, themselves, have continued their labors until the present day. 746. A great proportion of our ministers, no longer than fifty years since, were settled on farms, with salaries of from two, to three, and seldom, four hundred dollars per year. They were therefore under the necessity of labor- ing with their hands, in order to maintain their families. Besides, their flocks were often so scattered as to occupy a considerable portion of time, and some bodily exercise, in order to visit the several families even once a year. At these visits, the minister always received presents of pro- visions from his parishioners, but in case the visit was not made, the present was not given ; a good old custom, which always insured every family in the parish a personal acquaintance with their minister. 747. At that period, too, the mental labors of the clergy were not more than about one third what they are at the present day, especially in towns. They preached two <&H- mons a week ; in addition to which, an extra sermon once a month, or once in two months, preparatory to the com- munion, made up their stated labors. 748. Here it is obvious that the exertions of the mind were not, disproportioned to those of the muscles, and hence the clergy were then among the longest-lived individuals of their parishes, as is proved by the living witnesses of that body which here and there still remain. 749. It is unnecessary further to contrast the parochial labors of the clergy of the present day, writh those of their fathers in the church. It is well known that the increase of population, as well as a more advanced state of edu- cation, have rendered it necessary to increase these la- MUSCULAR EXERCISE OF LITERARY MEN. 237 bors more than twofold. At the same time, as their fathers required no extra exercise — no relaxation from their parochial duties, the public appear to have grown up in the belief that their sons do not ; and that it would be derogatory to clerical sobriety and dignity, for them to indulge in any sort of pleasant unbending of their minds. 750. Different Effects of Exercise. — Sawing and split- ting wood, with perhaps a little work in the garden, and riding on horseback a few miles, or walking the streets for an hour or two, form the chief amusements, and the chief muscular exercise of the most laborious, and in the esti- mation of the great majority of the people, the most useful body of men in community. Even this small amount of exercise is seldom taken regularly, and if so, is of very little use to the subject, as there is no other object in view but merely to perform a duty. The thread of the next discourse frequently remains unbroken, and often the individual hurries home while the ink of his last paragraph is hardly dry, to record some new idea, or write down what he has made ready in his mind during his absence. 751. To one whose body and mind begins to suffer, in consequence of confinement to his study, and perpetual mental exertions, nearly all who have experienced its ef- fects, will allow that such exercise is of little or no use. Such a one wants a motive ; he wants cerebral excite- ment to co-operate with and invigorate muscular action ; and it will astonish those, who, for the first time, notice the different effects on their own feelings, of forced mus- cular exertions, and that sanative exercise which is pro- duced when the mind is intensely fixed on an object, the attainment of which requires the strongest corporeal ex ertions. The one induces fatigue of the body, without at all relieving the mind ; while the other, so far from pro- ducing fatigue, brings the whole system into a highly pleasant state of freedom and elasticity ; 'while the mind, sympathising with these pleasant sensations, becomes in- vigorated, and is again ready for the performance of its proper functions. 752. Continued muscular Efforts to require Cerebral Excitement. — The principles of physiology which we have 238 MENTAL AND PHYSICAL EXERCISE. already explained, show, most decidedly, that continued corporeal exertions may be maintained under the stimulus of the mind, which the same individual could not possibly sustain under coercion. . 753. We see the exercise of this principle every day. A boy with his kite or gun, will exert all the powers of his muscles for five or six hours, or even for the> whole day, and still hardly complain of or feel fatigued ; while the same amount of muscular power exerted against his will, could not possibly have been sustained, though his life might depend on the performance. 754. Dr. Darwin9 s Case. — A case mentioned by Dr. Darwin, illustrates our subject. A young man full of de- sire to see his female friend, who was fifty-five miles from him, decided to undertake the journey on foot the next day ; and which, under the stimulus of hope and expecta- tion, he performed without difficulty. Having arrived at her residence, he found that she was attending a ball in the vicinity, to which place of course he repaired without delay. Here were new causes of excitement ; the object of all his thoughts he now saw dressed in gay attire ; the music, the friends, the dance, all tended to make him for- get his long journey ; and, as though fresh from the neigh- borhood, he joined in the pleasures of the evening, and danced most of the night with his wonted vigor and vi- vacity, and all this without fatigue. 755. Now had this performance been commenced by compulsion, that is, had this person been made to take the same number of steps at the command of a master, and then in the ball-room had he been compelled by the whip to use the same gestures that he did with his lady, at the sound of the music, what think you would have been the consequence ? Undoubtedly he would have sunk down and died from exhaustion, under such treatment. 756. In armies, it is well known that long marches can be endured under the excitement of music ; while without this, many of the soldiers would be unable to per- form the duty required, and would be left behind even in the country of the enemy. In forced marches, therefore, the commander who understands this, divides his mu- NATURE REQUIRES EXCITING EXERCISE. 239 sic, so as to keep a part of the band constantly playing such airs as to accommodate the pace of the marching soldiers. 757. The same principle is involved in the attempt of an adult to follow a child of three or four years old where- ever it chooses to go for a whole day, taking a similar number of steps, and using similar gestures. A healthy, active child, if entirely unrestrained, will soon convince the unthinking adult who undertakes such a task, that he has a day's work before him which he little expected ; nor do we believe it in the pow,er of many persons to per- form such a feat. The reason is obvious : the child is constantly excited by his play, and by a succession of new objects and new motives ; while the adult, having no mental excitement, by which the nervous influence is sent from the brain to the muscles, their contractions are merely mechanical, and therefore they soon become ex- hausted. 758. A parallel case is, where two men of equal mus- cular powers go out on a sporting excursion, the one a keen and ardent sportsman, and the other going as a mere spectator. The former having a motive, and being con- stantly intent upon his game, but not thinking of himself, will traverse bogs, bushes, and briars, for miles, without being aware of distance, or time, or place, and without feeling the least fatigue ; while the spectator, trying to keep with his companion, without any other motive than doing so, soon becomes so exhausted as to be incapable of further action, often wondering at the same time, how it is possible for his companion to go at such a rate, through such walking, and for so long a time, without complaining of fatigue. NATURE REQUIRES EXCITING EXERCISE. 759. It is in vain to plead natural gravity, or a want of disposition to indulge in those exercises which relax the mind of the studious, as an excuse for denying them to others, or not adopting such for ourselves. Nature, whose laws we profess to follow in this matter, makes no such excuse. On the contrary, unless the system be worn out 240 MENTAL AND PHYSICAL EXERCISE. with age or sickness^ there exists in the feelings of every person a natural disposition for play, both in the mind and muscles ; and where the restraints of society •« circumstances are removed, we may everywhere ob- serve illustrations of this law of nature. Hence at watering places, at the seashore, or any other place devoted to public amusement and relaxation, persons of the most erect gravity at home, and even members of the sacred office, throwing off the mantle of restraint, which had, perhaps, for a quarter of a century, hid their natural dispositions, not only from all their associates, but almost from themselves, again become boys and play all sorts of recreative games, with as much interest, and nearly with the same agility, as they did twenty or thirty years before. 760. Men bound to use Exercise which conduces to Health. — Now we do not make the above remarks by way of accusation, or for the purpose of hinting that such in- dulgences involve either hypocrisy or levity. On the contrary, such facts illustrate and confirm the principles of organic life which we have attempted to establish with the best intentions, and for the best of purposes. They show that, nature is averse to the solemn restraints of so- ciety, and that exciting exercise, because it is most agree- able and most natural, is the only kind which relieves the body and mind, when the first has become torpid from too little, and the last from too much exercise. And for the purpose of verifying these principles we would call upon those who now and then yield to the mandates of nature (whatever may be their acquired gravity), and reckless of muscular power, or mental reputation, enjoy for a time some sort of exciting play, to say whether the effects are not only congenial both to body and mind, and whether they do not believe, that under such amusements, frequently repeated, a man would perform a greater amount of mental labor, and continue longer in health and in life, than he would to proceed in the usual manner, of either taking no exercise at at all, or only that in which the muscles are compelled by force to perform their duty, as is the case with most NATURE REQUIRES EXCITING EXERCISE. 241 literary men ? If this is so, and which we are confident that not a man who has made the trial will deny, then is it not the moral, and even religious duty of every student to so far coincide with the dictates and laws of nature, as to employ every means which are not immoral in their tendency, to enable him by the preservation of his health and life, to do every good in his power for the benefit of his fellow-man ? 76 1. Says the pious and learned Dr. Cheyne, " The studious, the contemplative, the valetudinarian, and those of weak nerves, if they aim at health, and long life, must make exercise in a good air, a part of their religion." 762. A man who believes himself to be a useful member of community, and who becomes conscious that his occu- pation, whatever it may be, requires laxation, and that if he does not indulge in it, his health will suffer, and his life will be endangered, -would certainly be considered by himself and by others, as wanting in a moral duty, if he neglected such relaxation. Under such circumstances, no one would doubt what would be the duty of a mechanic, both with respect to his family and his country ; and if the same moral rule holds with respect to literary men and ministers, then they are as much bound to employ brain-exciting means to preserve their mental vigor, as the mechanic is to relax from his labor, for it has been shown, we think, that no other means will effectually answer this purpose. 763. Effects of incessant Mental Labor. — On this sub- ject, the author of this work speaks from experience, and therefore knows that he tells the truth. For, having tried the ordinary routine of exercise, such as wood-sawing, gardening, &c., he has been compelled, against his form- er prejudices, to resort to " field-sports," with his pointer and gun, not only as the means by which he has been enabled to continue in a sedentary and studious profession, but also to preserve himself from the dreadful con- sequences of nervous excitability, and especially from the most horrid and appalling of all sensations, that which attends palpitation of the heart, from an accumu- lation of the nervous influence. The most acute pain is 21 242 MENTAL AND PHYSICAL EXERCISK. a comfort, and even a pleasure, when compared to » feeling from which the sufferer cannot avoid the beliei that his heart swells to twice , the natural size, occasion- ally turns over, backward and forward, and is every instant in danger of bursting open and spilling its vital contents into his chest; at the same time he feels that his pulse beats half a dozen strokes in a moment, and then stands still, until forced by the stimulus of the blood to begin the same rapid motions again. And yet all this, and even more than we dare to describe to the literary invalid, is according to the woful experience of the one who writes this, the consequence of study at the rate of fourteen hours per day, for a series of months. And yet all these symptoms were unfelt and forgotten during the most violent exercise in which the mind was intensely in- terested, viz, field-sports. 764. Mere Attention to Diet of little Use. — A spare diet, omission of dinner, vegetable food, bran bread, and indeed all the remedies which the science of abstemiousness can suggest, will never prove antidotes to these fearful sensations. A laborious student, like a laborious workman, requires nutriment, nor can he sustain himself in his lit- erary pursuits without it. It is true, that where the muscles are little exercised, the quantity of solid food may be diminished; but he who goes to work at a difficult piece of composition with a hungry stomach, will never finish it to suit himself until this sensation is satisfied. 765. An easy and comfortable state of the animal sys- tem is absolutely necessary for the student, and so far as we know, this is only to be attained by a generous diet, and exciting exercise, according to the wants and feelings of the subject. 766. As the use of medicine, diet, and rules of conduct, without muscular action, for the alleviation of- nervous palpitation, they are worse than useless, because they offer false hopes to the sufferer, and prevent his seeking the proper remedy in season. And we hereby warn those into whose hands these remarks may fall, and who are thus afflicted, never to be caught by such chaff as bran bread and its adjuvants, as a remedy for what can NATURE REQUIRES EXCITING EXERCISE. 243 only be cured by muscular motion. You may starve your- selves to skeletons, and, my friends, still your horrid sensa- tions will increase, until you adopt some exciting muscular exercise as a remedy. Let your stomachs take care of themselves, and never think of what you eat or drink, ex- cept at the moment, only taking the precaution k) be tem- perate in both, and by the use of such exercise, repeated every day, and increased according to feelings and circum- stances, of which you are the best judges, you will gradu- ally rid yourselves of all that train of symptoms incident to nervous excitability, which have been brought on by sedentary and mental habits. 767. It is not denied that there are great differences in the amount of literary labor which different men are capa- ble of performing under the same circumstances. We are perfectly aware that there are Thomas Tophams in the mental as well as in the muscular departments of hu- man exertions. But we write for those who labor under the common laws of the animal economy, — those laws which ordinarily govern the actions and powers of human beings ; and not for those, whose iron constitutions are equally unhurt by any amount of cerebral or muscular performances which it is in their power to accomplish. These are exceptions to the general laws which govern our species, and to such we have nothing to say, be- cause, not suffering from their labors, they require no remedies. » 768. Cheerfulness a Remedy. — The best tempered men, after long confinement to study, and who take no pains to cultivate a cheerful acquaintance with their friends, are observed to grow more or less morose in their dispo- sitions, until they finally contract such a habit of being out of humor, especially at home, as to become such dis- agreeable companions, that their former friends, if they call upon them at all, do it as a matter of duty, and not for the purpose of having a few moments of enlivening conversation, as formerly. Of this disposition, the subject himself often becomes sensible, which discovery, instead of showing him the necessity of relaxation, and joining in cheerful society as a remedy, too often only proves a MENTAL AND PHYSICAL EXERCISE. source of vexation, which increases rather than alleviates the evil. 769. Now both moroseness and cheerfulness are often acquired habits, arising from the circumstances in which the person is placed. Let one, for instance, to whom nature has given a pleasant disposition, be so situated in life as to be constantly perplexed with its cares, or let him be under the necessity of pursuing studies which do not interest his mind, and which, therefore, are a source of vexation to him ; and the contracted brow will become habitual ; and the vexed spirit which it indicates will finally become so far a second nature, as to be retained, even long after the circumstances which produced these unhappy results have ceased. Such is the force of habit. 770. On the contrary, we often see those whose dispo- sitions are far from being naturally pleasant, but who, mixing with enlivening society, and being placed in such conditions in life as to escape its corroding cares and per- plexities, finally become agreeable, and even courteous companions, having acquired happy dispositions, in conse- quence of being constantly pleased with their own condi- tions and circumstances. 771. But whatever their conditions in life may be, it is undoubtedly the duty of all persons to cultivate cheerful and happy dispositions. Christians in an especial manner are called upon to rejoice — to set examples of a happy state of mind, and to show by their countenances and- ac- tions, that they are contented with the lot in which Provi- dence has cast them. A sour, crabbed Christian, presents a combination of elements so heterogeneous, that the world are always doubtful whether they ever exist in the same person. How, indeed, do such adorn the doctrines they profess ? 772. It is true, that there are afflictions, under which, for a time, a happy countenance would betray a want of common feeling, and therefore would be unbecoming and improper ; but under all the ordinary cares and perplexi- ties of life, of which every one has more or less, we are bound by the duties we owe each other, as well as ourselves, to preserve and cultivate a cheerful spirit and disposition, and aside from levity of conversation, or NATURE REQUIRES EXCITING EXERCISE. 245 action, we cannot see the immorality or impropriety of so far giving way to the dictates of nature as to carry our pleasantries even to mirth, let our ages or professions be what they way. 773. Laughing a proper and healthful Exercise. — Man is the only laughing animal which the whole terrestrial creation affords ; and in the young, the indulgence of this natural propensity, in proper places, and under proper circumstances, is universally approbated ; youth being considered by all as the appropriate season of innocent merriment. But there are those who look upon the action of the risible muscles, as being incompatible with the gravity and solemn dignity of certain ages and profes- sions ; and therefore believe that such ought always to suppress their lively and facetious thoughts, and expres- sions, lest they should excite laughter in others, or give way to it themselves. 774. Now we have no desire that any one should do violence to his conscience in this respect, but while, aside from improper levity, we cannot imagine from what source moral evil would come in consequence of the exercise of the muscles of risibility in any human being whatever, it is certain that the act of laughter conduces to the health of the system, by the motion it gives to certain muscles, as well as by the attendant relaxation of the mind, and there- fore, as a mere secular action, is a very proper exercise for people of studious and sedentary habits. 775. The muscles concerned in moderate laughter are chiefly the diaphragm, and those between the ribs, but when the action becomes violent, those of the back and chest are thrown into motion, and the whole frame is shaken ; the lungs being at the same time alternately filled with, and exhausted of air, by rapid muscular actions, which sometimes amount nearly to convulsions, thus call- ing into contractile motion all the muscles of the trunk, and agitating the entire assemblage of the visceral organs, thus, perhaps, detaching any adhesions that might be in- cipient in these parts, and at any rate, giving vigor to the actions of the pipes and strainers, the secreting and the absorbing surfaces, the functions of which are so neces- 21* 246 MENTAL AND PHYSICAL EXERCISE. sary, that not only health, but even life itself depends upon them. 776. " Laughter" says Dr. Willieh, " is sometimes the effect of joy ; but it frequently arises from a sudden dis- appointment of the mind, when directed to an object, which, instead of being serious and important, terminates unexpectedly in insignificance. Within the bounds of moderation, laughter is a salutary emotion ; for as a deep inspiration of air takes place, which is succeeded by a short and frequently repeated expiration, the lungs are filled with a great quantity of blood, and gradually emp- tied, so that its circulation through the lungs is thus bene- ficially promoted. It manifests a similar effect on the or- gans of digestion. Pains in the stomach, colics, and seve- ral other complaints that could not be relieved by other means, have been frequently removed by this. In many cases, where it is purposely raised, laughter is of excellent service, as a remedy which agitates and enlivens the whole frame. Experience also furnishes us with many remarkable instances where obstinate ulcers of the lungs or liver, which had resisted every effort of medicine, were happily opened and cured by a fit of laughter artificially excited." 777. In cases, however, where the conscience is against the practice of laughing, little good may be expected from it. DIFFERENT KINDS OF MUSCULAR EXERCISE. 778. There is a great difference, in the amount of ex- ercise which men require, depending very much upon con- stitution and habit. There is also a selection to be made, with respect to adaptation to the mind, since what would prove exhilarating to some, might be mere drudgery to others. Those who require muscular recreation, ought therefore to select such as combine excitement with con- venience; the same being adapted, with respect to its greater or less violence, to the constitution and habits of the individual. FIELD-SPORTS. 247 MANUAL LABOR. 779. In schools for manual labor, there may be intro- duced employments which to some, will in a degree answer the purposes required. But these must be varied, so as to give motion to the muscles in different parts of the body. Plaining, sawing, turning the lathe, turning the auger, and chopping with the axe, will in succession bring all the voluntary muscles into play. But as we have seen, unless the subject can contrive to make all these employments exciting to the mind, very little advantage will be gained from them. If therefore the student con- fines himself to such kinds of exercise, he must undertake the construction of some article of furniture, requiring the products of these different branches of labor ; and if several will undertake the construction of the same article, there will be produced some degree of excitement, during the progress of the work, by a comparison of the different specimens produced. But if the labor is not sufficiently active to induce general and profuse perspiration, especially in the warm season, little good to the debilitated student may be expected from it. SCIENTIFIC EXCURSIONS. 780. Excursions into the country on foot, especially among woods and mountains, in search of insects, or botanical and mineralogical specimens, to those who are fond of natural history, produce considerable energy of feeling and action ; and during the warm season, for those who live in cities especially, is a far more rational and healthful mode of spending a few weeks, than the more common one of lounging about watering-places, where it is often found that there are neither wholesome lodging, wholesome excitement, nor wholesome exercise. FIELD-SPORTS. 781. Sporting with the dog and gun, and especially with a well-trained pointer, afford to those who have learn- ed to " shoot on the wing," the most exciting and healthful 248 MENTAL AND PHYSICAL EXERCISE exercise. In whatever light people who are ignorant of this mode of employing their mind, and muscles, may look upon those men who are exhilarated by such " boyish sports," it is certain that those who have enjoyed the fine flow of spirits which such occasions excite, and especially the invigorating consequences thus produced on the animal system, are seldom induced to think that such exercise is incompatible with the gravity of age, or office ; but more generally continue the practice, so long as the eye-sight enables them to see the game distinctly. 782. To the lovers of the dog and gun, partridge, quail, and woodcock shooting, are considered the most exciting, and healthful of all muscular exercise ; but it is too violent for those whose systems are not prepared to undergo considerable fatigue, though the literary dyspeptic will find, after a few experiments, that he can traverse woods, bogs, and mountains, with a degree of facility and pleasure, which will be a matter of surprise to him- self. Students of athletic constitutions are sometimes compelled to employ exercise of proportionate violence ; the ordinary routine of riding, sawing wood, &c., being insufficient to produce the effects required, even though they might excite the brain. 783. A gentleman well known to the author, who left an active, for a sedentary and mental employment, found that sawing and splitting all the wood for his family, did very little toward preventing his nervous, from predom- inating over his muscular system. The effect of this ex- ercise was to fatigue the muscles of his arms and fingers, so that it was often difficult for him to resume his pen on this account. He found also that tiring the muscles did nothing toward relieving the mind; nor was there sufficient excitement in the employment, or motive in the end to be accomplished, to induce its continuance until perspiration ensued. Finding therefore, that there would soon be an absolute necessity for his either relin- quishing the profession he had adopted, or of seeking some more exciting and athletic exercise, he returned to his boyish practices, and partook himself to woodcock and partridge-shooting as the most convenient, and at the same time, as that kind of recreation from which FIELD-SPORTS. 249 there was the greatest hope of relief. In this he has not been disappointed, but has been able to perform much more mental labor than when he spent the whole day over his writing-desk. Two hours per day, from five to seven P. M., in the summer season, spent in this manner, with a good pointer, will give all the exercise which mid- dle-aged men, of ordinary constitutions, require. During this time, the exhilaration of the mind, and the motions of the muscles, are constant ; not a little of the interest arising from the wonderful instinct and sagacity which a well-bred pointer dog exhibits in the field, and which the lover of rural sports, however often he has witnessed it, never sees with indifference. The admirer of nature, who for the first time beholds the phenomena which these animals exhibit, when " beating the field," and " standing at a point," wrill not only be intensely interested, but often struck with astonishment at what he sees. The dog runs backward and forward, a little before his master, with his nose elevated above the grass or bushes, until he scents the bird (which is always on the ground), when he walks slowly, and carefully, to within a rod or -two of it, and then stands perfectly still, with his nose pointing to the exact spot where the game lies. The sportsman pro- ceeding to the spot, sends the dog forward to "flush" the bird, and shoots it as it flies, the dog again standing until the game falls, when he bring it and lays it at his mas- ter's feet. 784. In these dogs the pointing is a natural property, or perhaps an acquired instinct, and may be seen in young animals of good blood, without the least training. The training, therefore, does not consist in learning the animal to point, but only to obey the commands of his master, with respect to the moment of flushing the game, of bringing it, and of keeping within a certain distance from him, &c. 785. And now who can account for the reason why this extraordinary property was conferred on this animal, unless it was intended by the Giver to be employed by man in the manner we have described ; for in no other respect can it be of the least use to the dog or his master. We cannot but believe, therefore, that there was design in 250 MENTAL AND PHYSICAL EXERCISE. this peculiar endowment, and that it was intended to be made useful to man. 786. It is true that there are objections to this kind of sport. To those situated in large towns, it would perhaps be nearly impracticable as a daily exercise ; and besides, there is, at least, a semblance of cruelty in it. With re- spect to the latter, howTever, the conscience may be greatly relieved by adhering to two rules, which true sportsmen never violate. The first is, never to shoot at any bird which is not fit for the table ; and the second, never to shoot at any bird that is fit for the table, unless it be on the wing. By adopting these rules, the beginner will have to account chiefly for motives, and intentions, since he wrill seldom be troubled by seeing his bird fall. Still, however, the excitement does not entirely fail from want of success ; and if the tyro will persevere for a few days, or until he has " bagged " a few " brace" of birds, he will then find his conscience perfectly at rest on the subject of field-sports, both with regard to intentions and overt acts. Sir Walter Scott was enabled to continue his great mental efforts by the use of this kind of exercise. ANGLING. 787. Those who do not require the violent exercise in- separable from sporting with the dog and gun, may per- haps find as interesting a recreation in angling ; which, ever since the days of that father of " brook-sports," Izaak Walton, has never wanted most honorable patrons. And it must be confessed, that on several accounts this is hard- ly excelled by any other recreative employment. Indeed, we have the pleasure of knowing many a trout-fisher, whose present enjoyments are greatly heightened by this .exercise, and whose useful lives will undoubtedly be pro- longed by its continuance. 788. One of these, a gentleman who has retired from an active employment, often expresses his thankfulness that he is attached to this recreation, considering it, inde- pendently of the pleasure it confers, as one of the most efficient causes of the fine state of health which he enjoys. ANGLING. 251 789. To those who have no feeling on this subject, angling might be supposed to want that kind of excite- ment, which we have* described as necessary to healthful exercise. But if such a one will only just touch on the subject in presence of a " lover of the rod," he will find his mistake : for there is certainly not a more enthusiastic body of men on the subject of sportive recreations, or rather recreation, than the anglers ; and to these, there- fore, it presents a source of all the mental exhilaration, both as a conservative and curative means, which could be desired. 790. But the uninitiated and the ignorant are ready to inquire, " From what source can this interest, this excite- ment, arise ?" To which inquiry we will reply, for we have more than once been witness to the intense feeling which men of gravity, and of sound minds, exhibit on such oc- casions. 791. In the first place, then, an early breakfast, and a ride of several miles on a May morning, with the expecta- tion of a fine day (that is, a little cloudy), and fine luck, are preliminaries by no means wanting in interest. 792. When arrived at the trout-brook, there is the preparation of inserting the joints of the poles, of fixing the lines, and seeing to the bait, during which nothing else can be thought of. But now the chief source of mental excitement begins. 793. The hook all baited, and ready, is thrown into the water, and perhaps a bite is instantly felt ; or as is sometimes the case, possibly the trout may jump out of the water and seize it ; and who could avoid feeling at such a beginning ? What cold heart could remain unmoved with such a crown of success ? But if no fish jumps up to welcome the bait ; if no bite, not even a nibble is felt, still the excitement does not fail, for what is not realized is every instant expected, and therefore, from the very nature of the case, the mind is constantly occupied, the brain con- tinually excited, and nothing but the expected bite can be thought of. 794. And then, after an early breakfast, a ride and a walk along the limpid, gurgling stream, with the mind in- tensely fixed on an object — then comes on an animal sen- 252 MENTAL AND PHYSICAL EXERCISE. sation, which, after a while, predominates over the mental feelings of the keenest — the most ardent sportsmen, and the cold dinner is taken with the keenness of appetite, and a degree of enjoyment, known only to those whose gastric organs have been prepared by such means. 795. After the day's sport is over, still the interest does not cease, for the parties recount to each other, on the way home, the pleasures and circumstances of the day. And finally, after such a day of exercise, both of mind and body, there follows such a night of repose as the stayer-at- home cannot appreciate — and such a breakfast in the morning as princes seldom enjoy. RIDING. 796. " Of all exercises," says Dr. Ticknor, " riding is most conducive to health, and to vigor of the constitution, but as a good thing may be improperly or imprudently used, so riding sometimes produces an effect contrary to what is intended. Those who are not accustomed to riding, are most apt to suffer — the pleasure and exhilara- tion being so great, that fatigue or exhaustion is induced when it is least expected. In cold weather, people unused to carriage exercise, are apt to think the same quantity of clothing necessary in walking, wrill be an ade- quate protection wlien riding. Often a person will not experience a sensation of cold, he will not be aware that his body is becoming chilled, till he alights from his car- riage, or till he approaches the fire, when he becomes fully sensible that his ride has been too protracted. Those who are in good health, do not often experience any more than a temporary inconvenience from this cause, but in the deli- cate, it insufficient to be followed by a serious illness. In summer, a drive toward nightfall, is truly delicious, and it is believed to be conducive to health — and so indeed, it is, with due precaution — but at such times females are gen- erally thinly clad, and a thin dress affords little protection from the damp and chilly air of an evening." 797. " There seems, in the present age, a wonderful propensity to be hurried through the world ; not only is it convenient for the man of business to be transported by RIDING. 253 steam at the rate of from fifteen to fifty miles ai> hour, but there is no pleasure in driving one's « own hired' horse at a pace of less than ten miles in the same space of time. Being thus hurried away, Pegasus-like, a just equivalent to sitting in the open air when the wind blows, in sailor's phrase, a : stiff breeze,' and to do this at sunset would be thought the very extreme of imprudence. There can be no objection to any man's riding with all the speed his horse can make ; but it were wisdom to shield himself against a breeze of his own raising. 798. " Equitation, or riding on horseback, is a different exercise from the preceding ; and fast riding is not only active exercise, but severe labor. This is one of the most noble, and manly, and healthful exercises that can be imagined ; and as it formed a part of the education of the Spanish youth, so ought it to be made a part of the educa- tion of the young of both sexes, in our country. Riding on horseback, exercises every muscle, and every organ in the body ; and causes the blood to circulate so freely that in cold weather this is one of the most comfortable ways in which a person can travel, provided he can bear the exer- cise without fatigue. This may seem paradoxical to those who never have made the experiment, but the evidence of those who have tested it for several successive years, in all weathers, and at all seasons, has established the fact to my own satisfaction, that at the pace of seven or eight miles an hour, no person would feel cold in unusually severe winter weather."- — Philosophy of Livi?ig, by Caleb Ticknor, A. M., M. D., Harper's Family Library, No. 77, p. 202. 799. We will add to the foregoing judicious remarks of Dr. Ticknor, that riding on horseback, with agreeable company, and on a spirited, well-trained animal, does afford exercise at once agreeable, exhilarating, and manly. It also has the advantage of bringing all the prin- cipal muscles into play, and of shaking the viscera in such a manner as to give a vigorous action to the pipes and strainers throughout the system, and perhaps to de- tach any little adhesions that might be taking place among them. 800. A journey on horseback, for a nervous invalid, is undoubtedly one of the best means of restoration, not how 22 254 MENTAL AND PHYSICAL EXERCISE. ever, merely on account of the muscular exercise, or the wholesome air, but because there is a constant succession of new and exciting objects, which as constantly exercises the mind, and without requiring so much attention as at any time to create mental fatigue. Such a degree of mental excitement, with the muscular exercise, and pure atmo- sphere of the country, undoubtedly conspire to form a train of invigorating means hardly to be expected from any which can be employed at home. 801. It is entirely in consequence of the action of the brain thus excited, or the employment of the mind, ty the succession of new objects, that a journey produces such different results on the health of the invalid, from that to be obtained by ihe employment of the same amount of the same kind of exercise at one place. The fact itself, is well known, otherwise why do physicians order their patients to take journeys far from home, when with respect to the comforts and habits of life, they could be much better pro- vided for there, than abroad. Why not then ride thirty or forty miles a day, one way or another, and sleep at home, to which every invalid is attached, and to most of whom the leaving of their beds, rooms, and families, is such a trial as is often not easily to be overcome. From all we have said of the connexion which exists between the brain and muscles, the reason is obvious why little or no improvement may be expected from such exercise. The patient expects nothing new — he has already seen over and over again all that he expects to see during his ride ; he therefore begins his daily task without excitement, and going through it without interest, arrives at the place whence he started, i'atigued in body and mind, and discouraged not only because he finds no improvement, but because he dreads the idea of having to perform the same task on the morrow. - 802. On the contrary, during a journey, there is a con- stant change of scenery, or of objects, or of persons, which *is just sufficient to keep the mind in gentle and salubrious excitement, and which acting through the brain, supplies the muscular system with the requisite degree of ner- vous power, and thus the two systems (the muscular and nervous) are kept in a state of pleasant and healthy equilibrium, which conspires gradually to bring both into a condition of firmness and health. The patient, after HIDING. 255 such a day's journey, feels far less fatigue than when his exercise is without excitement, and he becomes satisfied that the means he is employing answers the purpose in- tended, £nd therefore, instead of being discouraged, he is filled with the hope of a final, and speedy recovery. 803. A highly intelligent female invalid, whose circum- stances allowed her to select the best means of improving her health, employed for a considerable time daily exer- cise, either on horseback or in an open carriage, in the form of little excursions from her residence. From this method, however, and for the reasons above stated, she obtained little else than fatigue, listlessness, and discourage- ment. Having relinquished it, therefore, for a journey through a fine country, at a good season of the year, she returned so much improved as to astonish her friends, as well as herself, that such a change could have been effect- ed in so short a period : and nearly every reader will no doubt remember similar cases, which have come within his own knowledge. 804. Exciting Exercise absolutely necessary to the studious. — And now, in closing this part of our subject, we cannot but desire to impress it upon the minds of those into whose hands this volume may fall, and who are des- tined to spend their lives in literary pursuits, or in clerical labors, that an uninterrupted and long-continued course of study, or of ministerial duties, without exciting relaxa- tion, is, from the very organization of our systems, in most cases, absolutely impossible. The kind of exercise must of course depend on the choice, or taste, or muscular powers of the individual only, to answer any good pur- pose ; as a restorative means, it must be exciting to the brain, and if possible, be repeated every day, or at least every two or three days, until the equilibrium of the system is restored, and when this is done, must be con- tinued habitually in order to insure a permanency of good health. 805. The above considerations and remarks, with re- spect to exercise in adults, although they do not apply im- mediately to youth, for whose instruction this work is chiefly intended, still it is hoped will not be deemed en- tirely out of place, since it is highly important that the 256 MENTAL AND PHYSICAL EXERCISE. rising generation should possess proper conceptions with respect to the arduous duties of the clerical office, and also that our young men, who are destined to follow the pur- suits of science, or literature, should at the commencement, know the importance of habitually using so much corpo- real exercise, as to prevent their falling into that nervous and debilitated condition, under which but too many of their brethren are now laboring. 806. Sir Walter Scott.— Sir Walter Scott, who pro- duced in the course of little more than twenty-five years seventy -four volumes of original romances, beside histo- ries, poems, biographies, critiques, and dissertations, so numerous, that so far as we know, their number has not been computed, and who at the same period employed many hours every day in other mental labors, still found time to take a great deal of amusing muscular exercise. Beside his dogs and gun, of which, being a capital shot, he was exceedingly fond, and with which he exercised himself with all the keenness and ardor of a first-rate sportsman, he also, nearly every day in the season, did something in the practice of cultivation, never taking a walk about his grounds without a weeding or pruning hook in his hand, thus always, even when most at leisure, placing before himself some object of amusement, or mo- tive of action. 807. It is well known, that for a long time there was a mystery with respect to the author of the Waverly Nov- els, and it now appears that the apparently constant occu- pation of Scott, as clerk of the sessions, and in other employments, was considered as a sufficient reason why it was not possible that he could have been their author. " In order to thicken this mystification," says one of his biographers, " Scott,' instead of being always at his wri- ting-desk, as might have been expected in so voluminous an author, seemed through the whole day and evening to have his time perfectly at command, for the routine either of business or amusement." " Three hours per diem" as he often observed, " are quite enough for literary labor, if only one's attention is kept so long undistr acted ; and the best time for this is in the morning, when other people are asleep." RIDING. 257 808. In conformity to this practice, Sir Waiter Scott used to produce twenty-four pages of quarto manuscript between the time of rising, and ten o'clock in the morning, when the court opened, and at which time his office re- quired his presence. This was closely written, in a small hand, and ready for the press. It is probable, however, that no authorities were consulted during this time, and that he previously had the matter all ready in his mind, otherwise such performances, if continued for any length of time, must be considered as little less than miraculous. 809. We have cited Scott to show the necessity, and the practice of active amusements in a man of letters, be- cause his writings are generally known, and because it might be supposed by some, that the great number of his productions, and the rapidity with which they followed each other, precluded the possibility of his spending any considerable portion of time in bodily exercise, whereas we see, that this was, at least for a time, the very means by which he was enabled to perform such extraordinary mental efforts. Nor was Scott an exception in this respect, to the practice of other British authors, and especially those of Scotland, who, whatever their ages, or offices may be, are in the habit of making play a part of their daily duties. 810. But notwithstanding Scott understood so well the principles which ought to govern students with respect to muscular exercise, and for a long time reduced them to practice, still his pecuniary embarrassments forced him to such unparalleled mental exertions as finally to affect the cerebral and nervous functions in such a manner as to in- duce a morbid condition of the whole system, from which he never recovered. So that the noble part by which he distinguished the age in which he lived, finally became the instrument by which he was destined to perish. A striking commentary on the principle that the equilibrium of the nervous and muscular systems cannot be deranged with impunity. 811. It has been not unaptly observed, by more than one of our transatlantic brethren, on visiting this country, and noticing our manners and habits, that, " the Americans 22* 258 MENTAL AND PHYSICAL EXERCISE. are v ery complete masters in the art of working, but they do not yet understand the art of playing" This is un- doubtedly true ; the newness of our country, originally, and some parts of it at the present time, making it necessary for all classes to labor more or less with their hands, and to this circumstance the present prosperity and vast enter- prise of our nation are in a great measure owing. It is from the same cause, also, that, as a nation, we have acquired the almost universal sentiment, that a man ought to labor constantly, and with little or no relaxation so long as he is able, let his occupation be what it may ; and this opin- ion is followed by a practice nearly as universal. Now, so far as muscular labor is concerned, this practice is not incompatible with the prospect of a long life and robust health, and therefore, whether followed from necessity or for profit, or pleasure, seldom so deranges the balance be- tween the muscular and nervous systems as to induce pre- mature evil to either. 812. But if, instead of depending upon foreign authors for our literature and science — if we are to look to the pens of our own sons and daughters for boofe of instruc- tion for the rising generation, and for even but a small portion of the mental food which this vast republic re- quires, then it is certain that so far as this class is con- cerned, the sentiment requiring perpetual labor must be changed, for, as we have abundantly shown, the Creator did not form man for incessant mental labor. PHYSICAL AND MENTAL EDUCATION OF YOUTH. 813. The proper use of the muscles consists in their alternate contraction and relaxation, and this is one of the most imperious laws of the animal economy. If the mus- cles are allowed to remain in a state of relaxation for any considerable time, they become incapable of vigorous con- traction, as we have already stated. The cases of prison- ers loig confined in cells, or in chains, so that they could not ase their limbs, have often presented lamentable illus- trr Jons of this principle. Such persons, without any posi- t' ve disease, become unable to walk, or even to stand, from mere debility of the muscular system. The deplorable case EDUCATION OF YOUTH 259 of poor Caspar Hauser, who was confined from his infancy in a small dungeon, and whose story is everywhere known, presented a still more striking and miserable example of the same principle. 814. On the contrary, if relaxation gradually destroys tlie strength of the muscles, so are their powers most rapidly exhausted by continued contraction. This indeed appears to be impossible for any considerable length of time. To hold the arm in a horizontal position, for ten minutes, even without any weight in the hand, is what no one can do without pain. To stand perfectly still on both feet, is also a most fatiguing position, because, in this pos- ture the muscles of the limbs are under continual tension. Hence it is, that soldiers, who are capable of enduring great exertions in marching, soon become impatient and tired, if kept beyond a certain length of time in the line, on parade ; and hence, also, the necessity that the drill- officer, who would have his men appear well on parade, should often employ the word " rest" in its military sense, it being impossible for them to keep the line in the atti- tude of soldiers more than a few minutes at a time. 815. If, then, men, and soldiers too, are incapable, from their organization, of avoiding the relaxation of their mus- cles, how much more difficult it must be for children and youth, whose limbs are instinctively in perpetual motion, to restrain themselves from this natural propensity. Rest, to these young creatures, after a time, undoubtedly becomes much more painful than any degree of hunger or thirst they have ever felt ; for these wants it would be consider- ed the highest cruelty not to supply. But the child, often, as every parent may have observed, after coming out of school, prefers the exercise of his muscles, for a while, to the gratification of his hunger. 816. Consequences of the confined Position of Females at School. — " The Principles of Physiology, applied to the Preservation of Health," by Dr. Combe, of Edinburgh, contains some capital remarks on the subject of muscular action in youth, and which are undoubtedly applicable, though it is hoped only in a limited degree, to our own country. 260 MENTAL AND PHYSICAL EXERCISE. 817. "Although contraction and relaxation," says the author, " or in other words, exercise of the muscles which support the trunk of the body, are the only means which, according to the Creator's laws, are conducive to muscular development, and by which the bodily strength and vigor can be secured. Instead of promoting such exercise, however, the prevailing system of female education places the muscles of the trunk in particular, under the worst possible circumstances, and renders their exercise nearly impossible. Left to its own weight, the body would fall to the ground, in obedience to the ordinaiy law of gravi- tation; in sitting and standing, therefore, as well as in walking, the position is preserved only by active muscular exertion." 818. " But if we confine ourselves to one attitude, such as that of sitting erect on a chair — or what is still worse, on benches, without backs, as is the common practice in schools — it is obvious that we place the muscles which support the spine and trunk, in the very disadvantageous position of permanent, instead of alternate contraction, which, we have seen, is in reality more fatiguing and de- bilitating to them than severe labor." 819. " Girls thus restrained daily, for many successive hours, invariably suffer — being deprived of the sports and exercise after school hours, which strengthen the muscles of boys, and enable them to withstand the oppression. The muscles being enfeebled, they either lean over insen- sibly to one side, and thus contract curvature of the spine, or, their weakness being perceived, they are forthwith cased in stiffer and stronger stays — that support being sought for in steel and whalebone, which Nature intended they should obtain from the bones and muscles of their own bodies." 820. " The patient, rinding the maintenance of an erect carriage (the grand object for which all this suffering is inflicted), thus rendered more easy at first, welcomes the stays, and like her teacher, fancies them highly use- ful. Speedily, however, their effects show them to be the reverse of beneficial. The same want of varied motion, which was the prime cause of the muscular EDUCATION OF YOUTH. 261 weakness, is still further aggravated by the tight pres- sure, of the stays interrupting the play of the muscles, and rendering them in a few months more powerless than ever. 821. " In spite, however, of the weariness and mischief which result from it, the same system is persevered in ; " and, except during the short time allotted to that nomi- nal exercise, the formal walk, the body is left almost as motionless as before, the lower limbs only being called into activity. The natural consequences of this treat- ment are debility of the body, curvature of the spine, impaired digestion, and, from the diminished tone of all the animal and vital functions, general ill health : — and yet while we thus set Nature and her laws at defiance, we presume to express surprise at the prevalence of female deformity and disease." 822. In the " Cyclopedia of Practical Medicine," the same subject occupies the attention of several writers, and sufficient proof is there adduced that Dr. Combe has not been mistaken in his apprehension with respect to the consequences of the course of physical education above described. 823. Dr. Forbes, one of the writers above referred to, says that he " lately visited a boarding-school in a large town, containing forty girls, and that he learned on close and accurate inquiry, that there was not one of these girls who had been at the school two years (and the majority had been there as long), that was not more or less CROOKED." 824. " Our patient," he continues, " was in this predica- ment ; and we could perceive (what all may perceive who meet that most melancholy of all processions — a boarding-school of young ladies in their walk), that all her companions were pallid, sallow, and listless. We can assert, on the same authority of personal observation, and on an extensive scale, that scarcely a single girl (more especially of the middle classes), that has been at a boarding-school for two or three years, returns home with unimpaired health ; and, for the truth of this assertion, we may appeal to every candid father, whose daughters have been placed in this situation." 825. In th'e same work it is stated by Dr. Barlow, that, it least in some boarding-schools, it is the practice to allow 262 MENTAL AND PHYSICAL EXERCISE. the young ladies only one hour of exercise, consisting of a slow walk arm-in-arm on the high road, and that even this, only when the weather is fine, — while their tasks in school are continued nine hours ; beside which, they are occupied three and a half hours per day, in optional studies, or in works. 826. Dr. Barlow further remarks, that the superintend- ents of these schools are generally extremely anxious about the welfare and health of their pupils ; and that it is through ignorance of the consequences, that such a course is pursued. 827. How far these strictures are deserved by the su- perintendents of boarding-schools in this country, the author does not pretend to judge. It is, however, well known and acknowledged, that the subject of popular education in this country is better understood than it is in Great Britain, or perhaps in any part of Europe ; and we may therefore perhaps justly infer, without reference to the facts, that at least some of the pernicious usages still re- tained in their schools, no longer exist here. 828. It is, however, believed, that a reference to the facts will show, that, at least in New England, the boarding- schools, to a considerable extent, are in a measure free from deserving censure on account of confining their pupils too closely ; though we have no doubt that less study and more exercise, taken regularly, would be highly advanta- geous to the mental progress, and certainly to the constitu- tional firmness, of the pupils. 829. Instead of so many successive hours being devoted to study and to books, the employments of the young ought to be varied, and interrupted by proper intervals of cheerful and exhilarating exercise ; such as is derived from games of dexterity which require the co-operation and so- ciety of their companions. This is infinitely preferable to the solemn processions which are so often substituted for recreation, and which are rather hurtful than otherwise, inasmuch as they delude parents and teachers into the no- tion that this is really exercise ; whereas the slow, measured step, and the locked arms, and the solemn silence, show that there is not a single element of wholesome recreation in such a procession. 830. It has already been shown, that mental cultivation EDUCATION OF YOUTH. 263 • cannot be carried on without a proper and due proportion of corporeal activity, even in adults ; and it is well known that youth require much more action than their parents, in order that the several functions of the animal fabric may be properly developed, and ultimately gain their most per- fect condition. And who had not much rather see his child return home from school with a little less algebra, and a good stock of health, than to know that she had outdone her classmates, and obtained the highest prize, while the pallid cheek, and the crooked, emaciated frame, show that this has been done at the expense of her health ? 831. Boys may run through the streets, play ball, skate, snow- ball, fish, and hunt, while the fate of the poor girls • is fixed, and bound down to the sedate and measured walk, and this only for a short distance, and at stated times. And still the girls require full as much exercise as their brothers. It is true, as will be seen in another place, that the dress of females is far more pernicious in its conse- quences than that of the males ; and hence, in a degree, undoubtedly, we may account for the greater number of deaths by consumption in the former than among the latter. But is it not to be feared, that in many instances, a predis- position to consumption is acquired in females in early youth, in consequence of the want of those wholesome sports which the boys enjoy ? And is it not the duty of parents and teachers to look to this subject especially, and see whether there is not a prevailing error in this respect ? 832. Remarks of the Rev. Dr. Dick.-— The Rev. Dr. Dick, in his excellent work on Mental Illumination, has some good remarks on the subject of school exercises for the body. 833. ward ; the face, but not the front of the body, is to be turned toward the mark. The left arm must be held out quite straight to the wrist, which should be bent inward ; the bow is to be held easy in the hand, and the ar- row when drawn, should be brought, not toward the eye, but the ear." "The right hand should begin to draw the string, as the left raises the bow : when the arrow is three parts drawn, the aim is to be taken ; in doing this, the pile should appear at ~ the right of the mark ; the arrow is then drawn to its head, and immediately let go." The arrow passes along the root of the thumb and fore-finger. Fig. 127 represents a female archer, at the instant of shooting. ARCHLRY. 271 861. A person at the target is furnished with a card, marked off as follows, for the convenience of inserting the Names. | Gold. | Rod. | I. White. | Black, j O. White. JYotaLl Value.! 47) A B 24 20 43 names of the shooters and recording their hits. This will be understood by a reference to Fig. 124, together with the rules for estimating the value of the hits in the differ- ent circles already given. The account is kept on the card, by making a pin-hole through the compartments, corresponding to the circles on the target for each hit. 862. We have been thus particular in describing this sport, because we consider it one of the most healthful and appropriate in which young ladies can indulge ; and cannot, therefore, but hope that it will be introduced into boarding schools generally, as a recreation. 272 GENERAL CONSIDERATIONS WITH RESPECT TO HEALTH, AND DISEASE. 863. Disease may be regarded in three points of view, viz., First, in having no necessary connection with our conduct, but as being the result of circumstances entirely beyond our control, or knowledge, and inflicted upon us by a wise Providence, for the purpose of warning us of our mortality, and of bringing us to think more soberly of our moral condition, and of the great end of our ex- istence. Secondly, as the result of what we consider accident alone, or of external causes which we can appreciate, but which it would have been impossible for us to prevent. Thirdly, as the result of the direct infringement of one, or more of the laws or conditions of organic life, as de- creed by the Creator to be essential to the well-being, health, and activity of our systems. 864. As diseases, and accidents will occur without our participation, or means of prevention, the First, and Sec- ond views do not here claim our attention, and we shall therefore pass to the Third, under which ill health is sup- posed to arise from some infringement of those organic laws by which our systems are regulated. 865. Considering that the human frame is constructed to endure, in many cases, for eighty, ninety, or even as hundred years, it must seem extraordinary to a reflecting mind, that in some situations, one half of all who are born should die before attaining maturity, and yet, it is true that of 1000 infants born in the city of London, 650 formerly did not live to the age of 10 years. It is hardly possible for us to suppose that such a rate of mortality was designed by the Creator to be the unavoidable fate of our race, and this seems to be proved by the fact that this proportion of deaths has been greatly diminished of late years by the gradual improvement of the comforts of living, and a closer observance of the laws of organic life. 866. A hundred years ago, when the infants of the poor in the city of London, were received into the public HEALTH AND DISEASE. 273 charities, or brought up in work-hourses, where the air was rendered impure by numbers, and where little atten- tion appears to have been paid, either to food, or nursing, not above one in twenty formerly lived to see the second year ; so that out of 2800, so received, 2690 died yearly. But when the conditions of health came, by experience, to be better understood, and an act of Parliament ob- tained obliging the parish officers to send these little inno- cents to be nursed in the country, this frightful mortality was reduced to 450, instead of 2600, out of 2800. 867. Can evidence stronger than this be required to prove that disease, and death frequently arise from causes which man is able to discover and remove ; and is it not therefore his imperious duty to investigate and avoid such causes, by every means which Providence has placed within his reach ? 868. The different rates of mortality in crowded cities, and in country villages, very clearly demonstrate the in- fluence of impure air, and improper, or damaged food, in abridging human life. Even in the most civilized life, and the best managed communities, so great is the num- ber who are doomed to find an early grave, and so few die of the decay of nature, that we may well suppose that we have not, with all the philosophy and humanity of the present age, yet arrived at the maximum of health, and longevity ; but the advance already made in the art of procuring long life, gives every reason to believe, that perseverance, and the extension of knowledge with re- gard to the causes of disease, will, even for centuries to come, enable man to extend more and more, the comforts and the lives of the human family. 869. The progress of knowledge, and the increasing ascendency of reason, have already delivered us from many scourges which were regarded by the ancients as the unavoidable dispensations of Providence. In the days of imperial Rome, that capital, and her territories, were frequently almost depopulated by visitations of the plague and other pestilences, from which the present generation is, by a stricter observance of the conditions of health, entirely exempted. 870. In London, in like mariner, the same contempt for cleanliness, ventilation, and comfort, which produced such 274 GENERAL CONSIDERATIONS fatal effects on the Romans, caused similar results, and the plague swept off its thousands and tens of thousands, until that dreadful, but fortunate disaster, the great fire, came in the place of knowledge, and by destroying a great part of the city, and especially the crowded lanes, and sources of impurity, which the people had shown so little care to remedy, procured for the citizens, in conse- quence of widening the streets, perpetual immunity from the most terrific of pestilences. 871. By this, the world, as well as the people of that great city, were taught the grand practical truth that such awful visitations are not the wanton inflictions of a venge- ful Providence, but the direct consequence of the non- observance of those conditions by which the various vital functions are regulated, and by conforming to which alone, health can surely be preserved. 872. Small Pox. — Small pox is another scourge which annually carried off its thousands, and from which modern science bids fair to protect us, although half a century ago, any one who might have ventured to express such an expectation, would have been ridiculed for his credu- lity. Even before Jenner's immortal discovery of vac- cination, the improvement of medical science consequent on a better knowledge of the structure and functions of the human body, had greatly mitigated the fatality of small pox. 873. Formerly the patients were shut up, loaded with bedclothes, in heated rooms, from which every particle of fresh air was excluded, and stimulants were administered, as if on purpose to hasten the fate of the sick. But sounder views of the wants of the animal economy at last prevailed ; and by the admission of fresh air, the re- moval of everything heating or stimulating, and the administration of cooling drinks and other appropriate remedies, thousands were preserved whose lives would have been lost under the mistaken guidance of the older physicians. 874. Fever and Jlgue. — As late as the middle of the last century, ague was so prevalent in many parts of Britain, where now it is rarely seen, that our ancestors looked upon an attack of it as a kind of necessary evil, from which they could never hope to be delivered. In WITH RESPECT TO HEALTH AND DISEASE. 275 this instance also, farther experience has shown that Providence was not in fault. 875 By draining the land, removing manure, buildin houses in better situations, and obtaining better food a warmer clothing, it appears that generations now succeed each other, living on the very same soil, without a single case of ague ever occurring, where, a century ago, every man, woman, and child, was almost sure to suffer from it at one time or other of their lives ; thus again showing how much man may do for the preservation of his health, and the improvement of his condition, when his conduct is directed by knowledge and sound principles. 876. Ansorfs and Cook's Voyages. — If we wish for a still more admirable proof of the same practical truth, we have only to compare the condition of our seamen, in maritime expeditions undertaken a century ago, with their lot in the present day — the expedition against Car- thagena, or that of Anson, for instance, with those of Cook, Parry, and Ross ; or the health enjoyed by the crew of the " Valorous," with that of the seamen in the other vessels lying in the same harbor. 877. Prison's Voyage. — >Anson set sail from England, on the 13th of September, 1740, in the Centurion of 60 guns and 400 men, accompanied by the Gloucester, of 50 guns and 300 men ; the Pearl, of 40 guns and 250 men ; the Wager, of 28 guns and 160 men ; the Tryal sloop, of 8 guns and 100 men, and two victuallers, one of 400, and the other of 200 tuns. They had a long run to Ma- deira, and thence to the coast of Brazil, where they arrived on the 18th of December ; but by this time, the crews were remarkably sickly, so that many died, and great numbers were confined to their hammocks. 878. The commodore now ordered " six air-scuttles to be cut in each ship, to admit more air between the decks" and took other methods to correct the " noisome stench on board," and destroy the vermin, which nuisances had become " very loathsome ;" and beside being " most in- tolerably offensive, they were doubtless, in some sort, pro- ductive of the sickness under which we had labored." Such is the mild language used by the chaplain, Mr. Walter, in communicating these appalling truths ! On anchoring at St. Catherine's, 80 patients were sent on 276 GENERAL CONSIDERATIONS shore from the Centurion alone, of whom 28 soon died, and the number of sick increased to 96. Although this was nothing compared to what took place afterward^ it is nevertheless worthy of remark, for as yet they had suffered no privations or unusual hardships, except from contrary winds. The causes of disease lay entirely with- in themselves. 879. After a stormy and tedious navigation of three months around Cape Horn, scurvy carried off 43 more in the month of April, and double that number in May, 1741. Those who remained alive now became more dispirited and melancholy than ever ; which " general dejection added to the virulence of the disease, and the mortality increased to a frightful degree" 880. On the 9th of June, when in sight of Juan Fer- nandez, the debility of the people was so great, that, 200 being already dead, the lieutenant could muster only two quartermasters, and six foremast-men able for duty in the middle watch ; so that, had it not been for the assistance of the officers, servants, &c., they would have been un- able to reach "the island — to such a condition was a crew of 400 men reduced in the course of a few months. Within a year, out of upward of 1200 men, comprising the crews of the squadron, who had sailed from England, 335 only remained. 881. Spanish Squadron. — The fate of the Spanish squadron which sailed nearly at the same time, was still more horrible. The Esperanza, of 50 guns, lost 392 out of 450 men, and the other ships almost as large a proportion. It is true that in doubling Cape Horn, they encountered the severest weather and the greatest priva- tions, and that their deplorable fate was aggravated by these causes. But when we look to the conduct of later navigators, in circumstances equally trying, it is impossi- ble to resist the gratifying conviction that mortality like this forms no part of the designs of a beneficent Provi- dence, and that, for the best of purposes, our safety is laced, to a great extent, within the limits of our own 882. The late memorable expeditions of Parry, of Franklin, and more especially, of Ross, who, with few resources, spent upward of four years in the desolate WITH RESPECT TO HEALTH AND DISEASE. 277 regions of the north, with scarcely any loss of life, are examples pregnant with warning to all who are inter- ested in the future progress of man. 883. Cook's Second Voyage. — It may be said that the climate and situation of the two parties were dissimilar. In some respects the objection is well founded ; but Cook's second voyage round the world, in 1772, affords a paral- lel presenting so many points of resemblance to that of Anson, that no one can reasonably object to their com- parison. On this occasion the vessels selected were the Resolu- tion, carrying 112 men, and the Adventure, with a crew of 81. 884. Enlightened by former experience, Cook spared no pains to effect his equipment in the completest man- ner, and to lay in such stores of clothing and provisions as he knew to be useful in preserving the health of those under his command. Among these were malt, sour krout, portable broth, sugar, and wheat. Care was taken to expose the men to wet as little as possible, to make them shift themselves after being wet, and to keep their per- sons, hammocks, bedding, and clothes, perfectly clean and dry. 885. Equal care was taken to keep the ship clean and dry between decks ; once or twice a week it was aired with fires ; and a fire was also frequently made at the bottom of the well, which was of great use in purifying the air in the lower parts of the ship. To the last pre- caution too great attention cannot be paid ; as the least neglect occasions a putrid and disagreeable smell below, which nothing but fire can remove. Fresh water, vege- tables, and fresh provisions, were also eagerly sought for at every opportunity ; and these it was Captain Cook's practice to oblige his people to make use of by his own example and authority. The result of these measures we shall now see. 886. The two ships sailed on the 13th of July, 1772. Toward the end of August, then advancing toward the south, the rain " poured down, not in drops, but in streams ; and the wind being at the same time variable and rough, the people were obliged to attend so con- stantly upon the deck, that few of them escaped being 24, 278 GENERAL CONSIDERATIONS completely soaked ;" but although rain is a great promo- ter of sickness in warm climates, the airing by fires be- tween decks, and the other precautions were so effectual, that, on arriving at the Cape of Good Hope, only one man was on the sick list ; whereas we have seen that, after a similar voyage, the Centurion arrived on the coast of Brazil with 80 sick, of whom 28 soon died. As we proceed, the contrast becomes still more striking. 887. On the 10th of December, they met with islands -of ice ; and from that time till the middle of March, con- tinued their search for land with unremitting diligence, amid cold, hardships, and dangers, such as we can form a very imperfect idea of; and at last, on the 26th March, after being 117 days at sea, during which they had sailed 3660 leagues, they came to anchor in Dusky Bay, New Zealand. 888. " After so long a voyage," says Dr. Kippis, from whose Life of Cook these particulars are taken, " in a high southern latitude, it might certainly have been expected that many of Captain Cook's people would be ill of scurvy. This, however, was not the case So salutary were, the effects of the sweet wort • and several articles of provis- ions, and especially of the frequent airings and sweeten- ings of the ship, that there was only one man on board who could be said to be much afflicted with the disease ; and even in that man it was chiefly occasioned by a bad habit of body, and a complication of other disorders." 889. Advantages of obeying the Laws of Health. — Can anything be conceived more demonstrative of the advantages to be derived from investigating and obeying the laws of health, than these splendid results, when con- trasted with those on board of the Centurion 1 In the Resolution, cheerful activity, cleanliness, dry pure air, adequate clothing, and a suitable regimen, were found to carry every man unscathed through hardships and ex- posure, which, in the Centurion, from neglect of the same protective means, were severe enough to sweep off a large proportion of her crew. 890. As if on, purpose to place the efficacy of these measures beyond a doubt, it appears that in the month of July, 1773, the Adventure had many sick, and twenty of her best men incapable of duty from scurvy and flux, WITH RESPECT TO HEALTH AND DISEASE. 279 when the Resolution, with a larger crew, had only three men sick, and only one of them from scurvy. This dif- ference in the state of health of the two ships, was dis- tinctly traced to the crew of the Adventure having eaten few or no vegetables when in Queen Charlotte's Sound, while on board the Resolution, Cook was most particular in enforcing attention to this part of their dietetic regimen 891. In looking forward, to a still greater diminution of disease in the human family, it is cheering to fix at- tention to what has been already accomplished by the hand of authority. Had the same individuals who cir- cumnavigated the globe with Cook, or braved the north- ern winters with Ross and Parry, been left for the same number of years to undergo the ordinary vicissitudes of life at home, unrestrained in their inclinations and conduct by the constantly operating, and beneficent influence of a superior mind, it is morally certain that disease and death would have made greater havoc among them than ac- tually occurred amid privations and sufferings much greater than they were likely to have encountered at home. Hence the obvious and pressing necessity which exists of diffusing widely among society that species of knowledge which has proved beneficial in the hands of those who are fortunate enough to possess it. If human health and happiness may be thus effectually promoted by increased attention to the conditions which regulate the vital and animal functions, nothing can be more useful than to communicate to every intelligent being such a measure of knowledge as will enable him to (Jo that for his own improvement and safety, which government now does for those whose services it requires. 892. Diminution of Mortality in Different Countries. It appears that increased attention to organic laws, and improvement in the practical science of medicine, has of late greatly diminished the rate of mortality in several countries, and that by the same means, the present ratio will still be diminished, there is every reason to hope, and believe. 893. Dr. Hawkins, in his Medical Statistics, estimated that in 1780 the annual mortality in England and Wales was 1 in 40; in 1790 it was 1 in 45; in 1801 it was 1 280 GENERA I- CONSIDERATIONS in 47; in 1811, 1 in 50; and in 1821, it was no more than 1 in 58. 894. In large cities, the diminution of mortality is still more remarkable. In London, 80 years ago, the annual mortality was 1 in 20 ; it is now 1 in 40. In France, according to recent accounts, the annual mortality in the kingdom is 1 in 40 ; in Austria, 1 in 38 ; in Russia, 1 in 41; and in the United States of America, 1 in 40. In the city of Paris it is 1 in 32, whereas, in the same city in 1781, it was 1 in 25. 895. From all these statements, it is clear, that as knowledge increases in the world, the average life of man is protracted. PRECAUTIONS WITH RESPECT TO YOUTH. 896. Predisposition to Consumption. — The most im- portant time of life to persons who, by hereditary predis- position, or otherwise, seem especially liable to diseases of the lungs, is from the age of 14 to 20. At this period the system is under rapid growth, but wants that consolida- tion and bodily strength which will enable it to undergo much fatigue, either of body or mind. In most young people, the transition from adolescence to maturity is so rapid that for several years all the animal powers are tasked to enable nutrition to keep pace with the growth, and a corresponding debility of both body and mind is often observed to co-exist, indicating, in the clearest man- ner, the necessity of a temporary remission from such studies, and occupations, as require much exertion, or confinement, especially within doors. 897. During this period, the development, and health of the physical system, ought to be the chief matter of concern, after which, the system having acquired power and solidity, the mind, from being nearly torpid, will be- come active, and fit for exertion. 898. Indeed it is not uncommon at this period for pa- rents to despond with respect to the mental prospects of their children, owing entirely to physical causes; but when the system has acquired its proper consolidation, it is seen that the mind becomes energetic in proportion, WITH KESPECT TO HEALTH AND DISEASE. 281 and there is no longer any doubt with respect to the mental capacity of the youth. 899. In such circumstances, the best method is, relaxa- tion from study, quietness of mind, exercise in the open air, and residence in the country, to which may be added travelling', and change of scene, with agreeable company. Such treatment, if persisted in, will often protect the pa- tient from consumption, though it may be his lot to in- herit it from his parents. Whereas, if under the mistaken opinion that precautionary measures are a waste of time, a delicate, growing youth is allowed to continue at his studies, or his desk, till disease has actually commenced, the disappointed parents will often discover, when too late, the grievous error they have inadvertently fallen into. 900. It is at the approach of manhood, when both mind and body are in a state of transition, that dissipa- tion, whether by late hours, exposure to night-damps, or otherwise, propels with the most deadly force upon the constitution, and many delicate youth of both sexes meet an early dissolution from this cause, who, though predis- posed to consumption, might have escaped, .had they been persuaded to act with prudence during these two or three critical years. 1 901. There is no doubt that many youth acquire habits which lead to their own destruction, at boarding- schools, and this too without the knowledge, or even sus- picion of their instructers, though there may be no want of vigilance on their part. 902. Temperature and Clothing. — In winter, young people often suffer from being daily confined, for many hours in succession, without exercise, in rooms not suffi- ciently heated. This is a constant subject of complaint, it is believed, in all cold countries, where schools and academies are kept, and arises from no other cause than strained economy in the use of fuel. This is a sad, and no doubt often a fatal practice, especially to such as are predisposed to diseases of the chest, and lungs ; and to those who are not, there is hardly any exposure which tends more to diminish the standard of health, and induce insidious disease, than being confined to a cold room, for hours, without sufficient clothing, and without exercise 24* 282 GENERAL CONSIDERATIONS 903. Young people, in feeble health, may exercise themselves in the open air for a considerable time, by way of amusement, or labor, even when the temperature is below zero, not only with impunity, but with advan- tage ; but there is scarcely any constitution so hardy, as not to suffer by repeated confinement in a room so cold as to produce shivering. 904. In general, young people in full health, and hav- ing the use of their limbs, seldom complain of the cold at any season, provided their clothing is sufficient. We may therefore infer, whenever the complaint is made, either that the clothing is not suitable for the weather, or that some insidious disease is making its approach, and if additional protection still fails to produce the desired warmth, we may be sure that the subject needs medical investigation. 905. In children of scrofulous habits, the evolution of animal heat is commonly below the healthy standard ; hence their faces are pale, and their hands and feet are habitually cold. In such cases, nothing can tend more directly to induce and develop the disease in full, than confinement in cold rooms, and an insufficient quantity of clothing. Such children should always, in the cold sea- son, be well covered with flannel, and take abundance of invigorating exercise in the open air, care always being taken to prevent shivering in any situation. It is in vain that parents undertake to harden such young and tender ones by exposure ; they require the most sedulous care and protection, until age, and gradually increasing health carries them beyond the ravages of the disease. 906. Exercise of the Lungs. — Judicious exercise of the lungs is undoubtedly one of the most efficacious means which we can employ for warding off disease, and promoting their development. In this respect, the organs of respiration closely resemble the muscles, or organs of motion ; they are both rendered more vigorous and healthy by proper action, while by inactivity, both become weak- ened, and impaired in their functions. 907. It is true that the lungs, being composed of ex- ceedingly attenuated vessels, require more discretion in their exercise, than the muscles, especially when the for- mer are predisposed to disease, but when this is the case, WITH RESPECT TO HEALTH AND DISEASE. 283 t is mucn more important that they should be properly exercised than when no such predisposition exists. 908. The lungs may be exercised indirectly by such kinds of bodily, or muscular action, as is usual, as walk- ing, running, riding, jumping the rope, &c., and directly by the employment of the voice in reading, speaking, singing, or playing on any wind instrument. 909. In general, both should be conjoined, or used al- ternately, as convenience permits. Where the chief ob- ject is to improve the lungs, the kinds of exercise to be employed should be such as tend to expand the chest, as well as to give a free use of the lungs ; and among these are rowing a boat, fencing, playing ball, quoits, and other gymnastic exercised, where the arms are brought into violent action. 910. Where, either from hereditary predisposition, or otherwise, the chest and lungs do not appear to have common strength and development, every effort should be made from infancy to favor their growth and strength by using any or all of the above-mentioned exercises, as occasion offers. 911. Where no active pulmonary disease exists, action of the above kind may be carried so far as to induce free perspiration, taking care always to prevent taking cold, by a change of dress, or in cool weather, going into a warm room, when the exercise is over. APPENDIX. CONTAINING A DESCRIPTION OF THE ATTITUDES OF STAND- ING, WALKING, SITTING, AND LEANING; TOGETHER WITH REMARKS AND OBSERVATIONS ON SPINAL DISTORTIONS, AND THE USE OF STAYS. 911. THE attitudes which the human frame is capable of assuming, are exceedingly various, but physiologists have reduced them to two kinds, or classes ; the active, and the passive. The former includes all such as require the action of the muscles, as standing or walking ; the lat- ter, such as require no muscular exertion, as when the body lies prostrate. STANDING. 912. When we stand on both feet, considerable mus- cular effort is required to preserve the upright position ; and still more when we stand on only one foot. In either case, the centre of gravity, which is between the hips, must be kept over the base. 913. In the first attitude, the base of support is the space between the feet, including the breadth of the feet themselves in one direction, and their length in the other ; and hence when the toes are turned outward, in standing or walking, the base is enlarged. In the last, the base is the single foot only. During this position of the body, nearly all the muscles of the lower extremities, as well as those of the back, are in a state of continual action ; and this is the reason why we become sooner fatigued \vhen standing still, than when walking, in which the muscles are alternately contracted and relaxed. 914. When we stand erect, the vertebral column trans- mits the weight of the head, as well as of all the other 286 APPENDIX. parts of the body above the hips, down through the lower limbs to the feet ; and hence the necessity that this column should have great strength and firmness, as formerly shown. 915. In standing, if the spine is bent backward so as to throw the line of the centre of gravity behind the base, the position soon becomes painful ; since the muscles of the back must be in a continued state of unnatural ten- sion, in order to maintain this position, and also because the muscles of the lower limbs are unduly straightened, for the purpose of preventing the body from declining backward, and thus losing its balance. This uncomfort- able position is represented by Fig. 128. 916. The most natural posture in standing, is that which Fig. 128. Fig. 129. can be supported longest with the least fatigue, and this appears to be when the spinal column is kept in a posi- tion similar to that shown by Fig. 63 ; the muscles of the back being kepi: in only just sufficient action to main- tain the spine erect; the chest and arms, at the same time, being thrown forward, so as to bring the centre of gravity somewhat forward, rather than behind the base, as shown by Fig. 129. In this posture, all the muscles will be found to be in as complete a state of relaxation, as is consistent with the erect position of the body. 917. If the pupil will imitate a few times the different postures here represented, she will soon find by expe- rience, that one can be maintained much longer than the other STANDING. 287 919. The Foot. — In describing the parts concerned in standing and walking, we will begin with the base, or foundation. We will, however, only give a slight description of the bones of this part. The tarsus is that part which reaches from the heel to the middle of the foot, marked a, Fig. 130. It is composed of seven bones. The meta- tarsus, b, consists of five long bones, laid close together, and reaching from the tarsus to the roots of the toes. The phalanges, c, or bones of the toes, are so called be- cause each row forms a phalanx. Of these there are fourteen in the whole. Thus the bones of the foot are twenty-six in number. These are covered with cartila- ges, and supplied with tendons ; the first binding them together in the strongest manner, and the second giving them motion in all directions. There is indeed no part of the human frame which is put together with so much care, and so strongly guarded against accidents, as the foot. It is obvious that were this not the case, so small a part would not withstand the violent concussions to which it is subjected, in sustaining the whole weight of the body, in leaping and other exercises. 920. The two bones of the lower limb, the tibia, or shin-bone, andfbula, which is placed on its outside, form by their lower extremities, the inner and outer ankle- bones. These are articulated with the great bone of the foot, called the astragalus; by which a hinge-joint is formed, having also some lateral motion. 921. Now when we walk, this joint allows the foot to roll easily upon the ends of these bones ; so that the toes may be directed according to the inequalities of the sur- face over which we pass. But when the foot is fixed on the ground, the muscles instantly act in such a manner as to give the joint a firm support, so that the whole body rests upon it, while the other foot is carried forward. 922. In walking, the heel first touches the ground, at which instant the bones of the leg and foot are in the po- sition with respect to each other, represented by Fig. 130. If the legs were situated perpendicularly over the part which first comes to the ground, we should come down with a dead blow, or jolt, as one does who has a woo ien 288 APPENDIX. leg. Whereas, by this arrangement, the foot acts as a lever ; and by the action Fi^ 130> of the muscles, lets the weight of the body come down gradually to the ground. 923. But, notwith- standing these easy mo- tions of the foot, the whole becomes exceedingly firm, and fixed, when the weight of the body bears directly upon it ; so that the bones of the leg will be fractured, before those of the foot will be displaced, or will yield in the least. With respect to the action of the muscles connected with the foot, which are concerned in support- ing the body in the upright position, Sir Charles Bell speaks as follows : 924. " The posture of a soldier under arms, when his heels are close together, and his knees straight, is a con- dition of painful restraint. Observe then the change in his body and limbs, when he is ordered to l stand at ease ;' the gun falls against his relaxed arms, the right knee is thrown out, and the tension of the ankle-joint of the same leg is relieved ; while he loses an inch and a half of his height, and sinks down upon the left hip. This com- mand to l stand at ease,' has a higher authority than the general order. It is a natural relaxation of the muscles, which are consequently relieved from a painful state of exertion; and the weight of the body then bears so upon the lower extremities, as to support the joints in- dependently of muscular effort. The advantage of this will be understood, when we consider that all the mus- cular effort is made at the expense of a living power, which, if excessive, will exhaust the man ; while the po- sition of rest we are describing, is without effort, and therefore gives perfect relief. And it is this which makes boys and girls, who are out of health, and languid, lounge too much in the position of relief, whence comes permanent distortion." 925. The standing position is as firm as possible, when the two feet, directed forward on two parallel lines, are separated by a space equal to one of them. If the base WALKING. 289 of support is enlarged in a lateral direction, by separa- ting the feet, the standing becomes more firm in this di- rection ; but is less so from behind and before. When one foot is placed in a line before the other, the back- ward and forward support becomes firm, in proportion as the base is extended in these directions; while the right and left foundation is diminished to the breadth of the foot. 926. The importance of the toes in standing, will be seen, when it is considered that their loss will deprive the base of about one fourth of its length in that direction. In walking, the loss of these parts is a still greater mis- fortune ; the elasticity of the step being thereby so di- minished, as to give the gait the appearance, rather of one who walks on wooden legs, than on sound limbs. 927. Standing on one Foot. — With respect to standing on one foot, it is only necessary to say, that the base of support is reduced to the surface which the foot covers, and therefore that the muscles of the whole limb must be in strong action, in order to keep the body from falling in such a position, which consequently can only be sup- ported for a few minutes. WALKING. 928. In walking, the position of the body should be erect, the head being always kept over the centre of grav- ity. The step should be firm, with the toes turned out, so that the foot at each step will make an angle of about thirty-three degrees on each side of a right line projected forward on the ground through the centre of gravity. If the feet form parallel lines with each other in stepping, the gait is vulgar, and tottering from right to left, the base not being sufficient to give a firm support to the centre of gravity. If the toes be turned outward too much, although the lateral sides of the base are thereby extended, yet the movement is awkward and unseemly, especially in ladies, and the step will want that elasticity from the action of the toes, which give lightness and grace to the gait. TKe foot should be carried forward 25 290 APPENDIX. with the toes raised sufficiently to avoid impediments, but no higher, for no position of the foot in walking, is more graceless and vulgar, than that of placing the heel, with the toes so elevated, as to give them an apparent dread of the ground, as though they were covered with corns. Such a lifting up of the toes, together with their parrot-like crossing of each other in walking, form a gait which no well-bred person will practise, unless compelled to do so by deformity, for with common attention it may be avoided. 929. Pedestrianism. — With respect to the style of walking which gives the greatest velocity, with the least muscular expenditure, pedestrians have learned by expe- rience to adopt a manner peculiar to themselves. Capt. Barclay, who performed the extraordinary feat of walking a thousand miles in a thousand successive hours, inclined his body so as to throw the centre of gravity a little for- ward of the centre of the base, thus making its weight rest chiefly on the front of the knee-joints. His step was short, and he raised his feet only a few inches from the ground. Any person, it is said, who will try this plan, will find his pace quickened thereby ; at the same time his walking will be more easy to himself, and he will be better able to endure the fatigue of a long journey, than by taking the erect posture, which throws too much of the weight of the body, it is said, on the ankle-joints. Capt. Barclay always used thick-soled shoes, and lamb's- wool stockings. The former he found indispensable, and had them so large as to avoid unnecessary pressure. Ev- ery sportsman of the least experience understands this, never venturing on an excursion, however dry the walk- ing may be, with thin-soled boots. SITTING. 930. The postures which we take in sitting, are ex- ceedingly various, and, on some accounts, of the highest importance, especially to youth. Thus we may sit on the ground with the limbs extended forward ; or upon a low or high seat, with or without a back, and with the feet touching, or not touching the floor, &c. SITTING. 291 931. The sitting posture, even without the support of the back, can be maintained much longer than that of standing, because the centre of gravity is thrown nearer the base ; and because the weight is diminished, and con- sequently the muscular power required to support the erect posture, is lessened. But this position, without the support of the back, after a time becomes too painful to be endured with patience. 932. The sad consequences of long confinement in the sitting posture, without any support for the back, have already been described at some length under another head, but the more we have thought upon and examined this subject, the more important it appears, and we can- not therefore, in duty to the youth of our country, dismiss it without some further considerations and remarks. 933. Causes of Spinal Curvatures. — It is proposed here to trace the effects of the causes to which we have already referred with respect to curvatures of the spine, and to show why certain positions will make this defor- mity permanent. 934. The spine itself, detached from all other parts, is figured and described at p. 80, Fig. 63, where the light- colored transverse lines between each two vertebra show the cartilages of the spine. These cartilages are in the subject, about the fourth of an inch in thickness, and are compressible and elastic like pieces of India-rubber. Were it not so the spine would be rigid, and unyielding as though it was formed of one continued piece of bone. Its motions, therefore, are in consequence of the elas- ticity of these cartilages, so that when the spine is bent, one of their sides, or edges, is compressed more than the other. 935. In the night, when we take the recumbent pos- ture, and there is no pressure on the spinal column, these elastic plates swell and become thickened, but their thick- ness is again reduced by the weight of the body during the day, and especially in laborers who carry weights on their heads. The diurnal difference in the thickness of each cartilage, from these causes, it is true, is very slight, but their number is such as to make an apprecia- 292 APPENDIX. ble difference in the length of the column at different times. In young persons the elasticity is much greater than in the aged, these parts gradually hardening with the years a person lives, until the spine finally loses a great proportion of its flexibility, and in these circum- stances, there is very little diurnal difference in the length of the column. But in youthful persons the difference in the length, especially if they are tall, between morning and evening, may be from half to a quarter of an inch, and may be found by the common mode of measuring. Thus do we grow taller during the night, and shorter during the day. 936. Now these cartilages, being thus compressible and elastic, in young persons, but gradually hardening with age, it is plain that if one edge or side, in such a one be pressed more than the other, and this pressure be continued for any considerable length of time, they will not grow of a uniform thickness, the part thus pressed becoming thinner, and the opposite part thicker than nat- ural. Without reference to growth, the same effect would be produced by the pressure of, and the gradual hardening of these parts. Therefore, if the spinal col- umn be bent into any unnatural shape, and the same pos- ture be continued day after day, and month after month, as is too often the case with young ladies at school, the cartilaginous plates will finally become wedge-shaped, having a thick and a thin edge, and as they harden with age, they will continue to operate as wedges in retain- ing the spine in that crooked state by which they were forced into this form ; and thus the person will probably become deformed for the remainder of her life, in spite of all the frames, pulleys, and weights, and other Pro- crustean apparatus, which may be applied to remedy the evil. 937. This effect would be produced in such persons as had not arrived at the age when the cartilages become hard. But in those who are quite young, as from in- fancy to twelve or fourteen years, even the bones of the spinal column being still comparatively soft, would con- form more or less to the curvature given it, thus making a deformity from which there is not the slightest hope of SITTING. 293 , since the great beam of the whole fabric has thus become permanently misshapen. 938. Sitting Postures described. — It might perhaps be considered unnecessary to give any instructions on the most comfortable manner of sitting, it being a natural supposition that every one would consult their own ex- perience in this respect. And yet, it may be the case, that a few observations and experiments on this subject, will be the means of diminishing the pain of those who are for any considerable time confined to this posit on, and thus avoid some of the evils which might otherwise arise from it. 939. The sitting posture, it will be found, soon be- comes painful, and is maintained with difficulty, when the inferior portion of the spinal column is bent inward, and the arms are thrown back, with an erect position of the neck and head. Even when the spine is supported by a back, as in a chair, this posture becomes uneasy, because the dorsal muscles, and those of respiration also, are kept in an unnecessary state of action. This position will be understood by Fig. 131. Fig. 131. Fig. 132. 940. The most comfortable posture in sitting, is that which at once relaxes the muscles of the back and those of respiration, the inferior portion of the spine being gently curved, but not made crooked ; while the upper part is nearly straight, with the neck a little inclined, so as to 25* 294 APPENDIX. relax the muscles supporting the head. This position is represented by Fig. 132. 941. A little experience, with these suggestions m view, will teach the pupil, it is hoped, to preserve a healthful and becoming position at school, without assu- ming the leaning posture, the consequences of which are so pernicious. LEANING POSTURE. 942. One posture which school-girls are exceedingly apt to take, is that of leaning forward, and placing the elbow on the desk for support ; and this they often do, even when their seats are provided with backs. This posture, if continued so as to form a habit, will often show its effects on all occasions, the young lady having such a disposition to lean, as to indulge it when any sup- port happens to be near where she sits, let the place or company be what it may. Such a one will lean, with the hand supporting the head, when at home, on a table, or window-stool, or any other convenient lolling-place, for hours together. 943. Where the spine is weak, in a growing girl, and there is predisposition to curvature, there is no posture that she can take, which is so unfortunate, and will pro- duce such a complication of deformities as this ; for if it is continued in one direction, which is commonly the case, the consequences will be a curvature of the lower part of the spine, together with one high, and one low hip ; one high and one low shoulder ; and a crooked neck. 944. The general deformity thus induced, is however often most apparent in the shoulder-blades, one of which is sometimes thrown so far out of place as to give it the appearance of absolute dislocation, and which indeed, is the case, when compared with its mate. Fig. 133. 945. The other deformities which we have mentioned as arising from the same cause, may in some degree be concealed or qualified by means of stays, extra padding, coussinets, and other efforts of the milliner's skill, with which we profess no acquaintance. But the dislocated shoulder-blades, especially when they are uncovered, seem to defy all the arts of the most profound dress-maker, for LEANING POSTURE. 295 neither stays, nor buckram, nor foundation-muslu: nor padding, can hide, but seem rather to magnify this de- Fig. 133. formity ; at least humanity would hope so, when the eye beholds how great it still remains, under the apparent use of all these remedies. 946. Far be it from us to speak with unkindness or levity on a subject which but too often calls for commis- eration and gravity. But when we see those who might, peradventure, have passed as specimens of symmetrical form among the fairest, and most charming of the Crea- tor's works, unveiling deformities (no matter what might have been their origin), merely for the sake of rivalry in the extent of the fashion, we cannot but lament in such, the want of common discretion, common prudence, or common modesty — for did these unfortunates but know how such revelations sometimes affect the minds, and per- haps even the hearts of those whose kindness and good esteem they cannot but value, they certainly would have sacrificed less to fashion, and more to decency and dis- cretion. 947. It is not pretended that curved spines, and de- ibrmed shoulders, are caused only by the leaning posture 296 APPENDIX. above described, or that every one who even habitually takes that posture will eventually become crooked. But in slender, delicately-formed females, from the age of twelve to fourteen, who are confined eight or ten hours per day in the school-room, with no other exercise than a walk along the street with their teachers, such a posture habitually indulged in, will most surely produce deformities to a greater or less extent. The Hindoo devotees who hold their arms above their heads as a pen- ance, are often compelled to carry them so during the remainder of their lives, the parts conforming to this position. 948. A highly observant and accomplished teacher, who has spent more than twenty years in the instruction of females, informs the author that he has long been aware of the distorting consequences of this posture, and that he could remember numerous instances of crooked spines and dislocated shoulder-blades from this cause : — and that although these very pupils were nearly every day warned of the consequences of such a habit, yet, not seeing, or feeling any ill effects from it themselves, they would carelessly indulge in it, until the posture became so natural, as to set all the common means of prevention at naught, and thus distortion followed of course. 949. Now if the young lady will give no attention to the mandates or remonstrances of her instructer, or pa- rent, there is little hope of preventing her indulgence in this, or any other pernicious habit, and such, therefore, must be left to the reward of their own doings. But in most instances, it cannot but be hoped and believed, that those who are aware of the sad consequences of this habit, both in respect to personal form and health, whether they become so by reading these observations, or other- wise, will take warning in due time, and thus escape that deformity which is now but too common among our best educated females. DRESS, ANOTHER SOURCE OF DEFORMITY. 950. There is, or at least has been,, another cause of distorted shoulders beside that above described, and the DRESS ANOTHER SOURCE OF DEFORMITY. 297 efforts of which, are in a great number of instances ap- parent, and will remain so during the present generation This is the recent fashion of dressing so wide across the neck as to leave one, or perhaps both tlie acromion pro- cesses, or shoulder tips, in a state of entire nudity. 951. The young lady, it is true, had the power, by muscular action, of hiding a part of one shoulder at a time, but the dress, if in good fashion, could never be made to cover both of these processes, except alternately, though it was quite easy to leave both uncovered. The conse- quence of this fashion was, that, judging from the per- petual motion of these parts, the wearer constantly felt as though her dress was in danger of .slipping down, and which she made as constant efforts to prevent, or to ascertain by feeling with the shoulder whether this was the case, or not, until these motions became habitual, and therefore insensible. As the dress was designed to cover only one shoulder at the same time, this partiality (for which shoulder it was intended, we know not) was always extended to the same one, because habit made it most natural and comfortable ; consequently the pres- sure on the two sides became unequal, and the wearer, to counteract this, or from the unnatural or uneasy feeling consequent upon confining one side, while its antagonist remained free, constantly and habitually elevated one shoulder while the other remained stationary, until the former became permanently higher than the latter. 952. Although this (without using any other epithet) pernicious fashion, we believe, is chiefly done away, at least among the fashionables, its consequences still remain, as many a monument of its existence can testify; and therefore we hope it will not be considered impertinent, or improper to record its history and consequences, that mothers may be aware of both, when its turn, in the never-ending circle of costumal changes, shall again come round. 953. Fashionable Deformity. — The vast number of in- stances, in which the causes already mentioned, or those which we shall hereafter notice, have occasioned female deformity, most of which might have been prevented, is 298 APPENDIX. a sunject of very serious consideration, for beside the personal defects thus induced, these causes, or their con- sequences often produce derangement in the functions of the viscera, which in their turn, superinduce either con- sumptions, or other lingering diseases, which it is exceed- ingly difficult, or impossible to remedy, and which there- fore end in death. 954. In cities, personal deformity among the higher classes has become so common, that it seems to form a characteristic of the age in which we live. A few years since, and perhaps even at the present time, such was the prevalence of curved spines among those females who gave tone to the fashions, that it actually became the ton to be crooked, and many fashionables, who had escaped any misfortune in this respect, contrived to give the upper part of their spinal columns a gentle curve, so as to imitate the fashionable stoop of these female ex- quisites. And in many instances where there was not the least intention of becoming permanently deformed, but only to be in the fashion for the season, this genteel stoop became a habit, and nature not liking such imposi- tions, has taken these poor devotees at their word, and having formed the cartilages of their back bones into wedges, has for ever prevented their regaining that noble position which it was intended that man alone, among all created beings, should assume. These are therefore doomed to continue in one, and the same fashion, for the remainder of their lives. EFFECTS OF PRESSURE ON THE MUSCLES OF THE BACK. 955. It is well known to physiologists, that if pressure be made, and continued on any part of the system, the part so pressed will be gradually diminished in conse- quence. Thus if one limb be tightly bandaged, for a length of time, it will become smaller than the other. 955. To understand the reason of this, it is necessary to state, that every part of the system is furnished with two sets, or kinds of vessels, called the capillaries, one set being designed to secrete, or produce ; and the other to absorb, or remove ; and that in the living animal, both EFFECTS OF PRESSURE OF THE MUSCLES. 299 Kinds are constantly performing their opposite functions. The flesh and all the other parts of the body are formed by the secretory system, which consists of the fine extremities of the arteries. We have already explained the manner in which the food is converted into chyle by the process of digestion, and how this is conveyed into the circulation, to be converted into bk>od. Now it is from the blood thus formed, that the secreting vessels produce all the different kinds of substance of which the several parts of the animal system are composed, one division forming flesh, another cartilage, and another bone, &c. All the fluids are also formed by appropri- ate organs belonging to the same system. Thus one set produce tears, another saliva, and another bile, and so on. 957. On the contrary, the absorbent system .takes up, and conveys from one part to another, the various fluids which are either employed in the process of secretion, or which being secreted in some cavity, or on some internal surface, and having performed its office, is to be conveyed out of the body. Thus the absorbents suck up the chyle by millions of mouths, and carry it to the thoracic duct, through which it is delivered into the cir- culation. They also absorb the superabundant moisture which is secreted in every interior part of the body, and consequently, did they cease to act, this watery fluid would accumulate, and a universal dropsy would ensue. This disease, as it occurs, is owing to the deficient action of the absorbents. 958. It is the office, therefore, of the secreting system, to produce and deposite the matter composing all the dif- ferent organs, and fluids of the body ; while the absorb- ents in their turn, take up and carry away, by slow and insensible degrees, the matter thus deposited. 959. Such being the appropriate functions of these two great systems of vessels, which are distributed to every part of the animal frame, it is plain that the iden- tical particles of which we are composed, are perpetually changing, and that in this respect we are not the same in- dividuals now that we were formerly, nor will our bodies at a future time, contain a particle of the identical matter which they do at this moment. 300 APPENDIX. 960. In childhood and youth, when the frame is grow- ing, the secretion is greater than the absorption;- — in adults, and the middle aged, the effects of the two systems are just equal, there being the same quantity of matter absorbed that there is secreted ; but in old age the absorp- tion is greater than the secretion, and hence the weight and dimensions of the body are diminished, and the skin, instead of preserving its tension, as formerly, becomes wrinkled in consequence of the loss of a part of the bulk which it covers. 961. Thus during one portion of our lives, we increase in size and vigor, until having arrived at maturity, we re- main for a time stationary in both; and then, lastly, having passed through these two stages, we begin im- perceptibly in both, to diminish, the animal functions gradually becoming more and more feeble, until one after another they cease to act entirely, when life gives place to death. -These are the immutable laws which govern all created beings, and which, therefore, no-human means can resist. All flesh must return to dust. APPLICATION OF THESE PRINCIPLES. 962. In applying these principles to the use of stays, it is almost unnecessary to say, that during the growth of the system, pressure, on any of its parts, though it may be inconsiderable in force, yet if long continued, will pre- vent their increase ; and this not only for want of room to expand, but also by interfering with the 'functions of the secreting system in that part. A lamentable illustra- tion of the practical use of this principle, is seen in the feet of the Chinese ladies; which being confined in iron shoes from infancy to the age of sixteen or eighteen, they remain infant's feet ever afterward, though terminating the extremities of the aged. 963. But, beside this obvious effect of confinement during the growth of the system, it is well known that in the adult, as well as in the young, pressure will also diminish any part on which it is made, as already stated at the commencement of these observations. Not only the soft, or fleshy portions of the system may be thus ab- APPLICATION OF THESE PRINCIPLES. 301 sorbed and removed, but even the bones do not resist the power of these minute vessels, portions of their solid parts being sometimes carried away by their action. Thus the enlargement of the aorta, or great artery (which passes down the spine), by a disease called aneu- rism, sometimes pressing against the interior sides of the ribs, cause the entire destruction and removal of the parts thus pressed. We have seen an instance where several inches of three or four of the lower ribs next to the spine, on the left side were entirely removed from this cause ; leaving a soft chasm, where the pulsation of the aneurism was frightfully apparent, both to the sight and touch. In the anatomical collection of Sir Charles Bell, there is preserved a specimen, showing the destruc- tion of the lateral parts of four spinal vertebrae, from the same cause. 964. Indolent tumors, caused by diseased action of the part are often reduced and sometimes cured by pressure on the part, which in these cases is employed as a cura- tive means. But it is unnecessary to quote more practi- cal examples of the fact, that pressure will both prevent the growth and diminish the bulk of any part of the living system on which it is made. This fact is indeed so common, that inveterate snuffers, who always carry a pinch between the thumb and finger, often acquire a little cavity in the ball of the former, where they keep this baneful luxury. 965. The pressure of stays around the waist, it is quite clear from the foregoing principles, must in youth, and while the system is growing prevent the full development of the muscles of the back, by presenting an impediment to their increase of bulk; arid if not assumed until the system has nearly or quite attained its full size, as at the age of sixteen or nineteen, still the consequences may be equally pernicious, since the form, in this case, will prob- ably be supposed to require a degree of tension in the lacing cords, somewhat proportionate to the time they have been delayed. The effect will therefore be to in- crease the absorption, and diminish the secretion of the parts pressed upon, and thus to reduce the bulk, and con- sequently the strength and vigor of the muscles. 966. Now the spinal column is chiefly supported in the 26 302 APPENDIX. erect position by the strong muscles of the back, called the dorsal muscles ; and if these by any means, are di- minished in bulk or vigor, the spine will inevitably be- come distorted ; and as we have shown that tight lacing produces the first effect, so it is equally certain that the last will follow. Thus the very means which a great proportion of the ladies of the present day, take to give themselves little waists, and consequently, as they con- ceive, inviting forms, become a deception, because' it is a wicked interference with the laws of nature ; and instead of producing the desired effect, in many instances at least, actually transforms them into crooked disgusting objects ; and in the sequel we shall see other consequences equally unfortunate from the same cause. 967. A mother who begins to corset her child at the age of ten or twelve years, intending to present to the world a few years hence, the " works or her own hands," modified and moulded according to her skill and taste, often finds that at the age of fourteen or sixteen, she be- gins to <: eat chalk," look pale and grow crooked. To remedy the first, she detains her at home, lest she should expose herself by going into the air, especially if the season is cool j but finding that under this treatment, she becomes listless and paler still, she consults the family physician, who very judiciously prescribes iron, and other tonics, according to art. 968. The crook of the spine, the mother undertakes to manage by her own skill, not letting the doctor know that anything is wrong in that respect ; but only that the girl is growing tall so fast, that she has hardly strength to keep herself straight — so that the most important part of the case is kept out of sight and not prescribed for. 969. The kind parent begins by procuring a more sub- stantial support for the back of her daughter, in the form of new stays, and which are made to order, with direc- tions to insert an extra quantity of whalebone and steel ; and perhaps this instrument of torture is padded at certain points so as to press with special force on that part of the spine which is most distorted, with the good intention of forcing it to its proper place. The means of cure being thus provided, they are put in their proper place, and the cords drawn with a force, in some degree pro- APPLICATION OF THESE PRINCIPLES. 303 portionate to the affection of the mother, and the amount of the deformity which it is intended thus to obviate. But contrary to the anxious expectations of the family, the evil not only continues, but increases ; and paleness, emaciation, loss of appetite, and general debility super- vene, notwithstanding the stays are tightened, and the tonics are repeated, with a liberal hand. But it is need- less to pursue the details of such a picture. It would in many instances lead us down to a premature grave, and we willingly leave the closing scene to those whose duties call them to witness it. 970. In such cases as we have above described (and we leave it to any city practitioner in ouc country, whether such do not often occur), the use of tight lacing, whether the patient has been habituated to stays, or cor- sets, from her childhood or not, is productive of the worst consequences. The muscles of the back have already been so diminished and debilitated by pressure, as to be unable to support the spine, otherwise there would have been no need of adding stronger stays ; and in this con- dition, a little reflection ought to show that the offending cause should be instantly removed, _or at least relaxed so as to allow the muscles free action ; and that this, with country air, time, and exercise, would afford the most reasonable hope of cure. But, by increasing the pres- sure, the healthy action of the muscles is entirely super- seded, and a condition at least bordering on palsy of the part, is induced, and thus the intended remedy increases, and confirms the distortion. 971. That these are some of the consequences which follow such attempts to produce fine forms, and to cure curved spines, could have been inferred from physiolo- gical principles; but without depending on inferences, almost every person of common observation has seen a sufficient number of living witnesses, to convince him that thousands of such cases, or at least cases of female deformity, do exist. 972. No fashionable dressmaker will deny, that One in four or five of her customers, among what are called first-rate young ladies, do not require padding, or stuffing, on one part or another, in order to conceal some deform ity, Qr make one side equal with the other. 304 APPENDIX. 973. Now we have nothing to do with the mere ex- travagances, or follies, if they exist, of the female cos- tumes of the present day ; our design being to speak only of such fashions, or habits of dressing, as produce deformities and disease ; and in this respect, and on this subject, there are facts so common and so deplorable that they ought to induce thousands to raise their voices and their authority against the practices to which their origin is plainly to be traced. EFFECTS OF TIGHT LACING UPON THE LUNGS. 974. It is true, that when the bones of animals are in a soft and pliable state, which is always the case when they are young, their natural forms may be modified, or moulded into almost any shape. Even the head, togeth- er with its contents, that noblest of all created organs in a reasoning being, can be changed from its natural form, to a parallelogram or cube, as the customs of the flat- headed Indians abundantly prove. Nor are we aware that this change produces any evil, either to the bodily health, or intellectual faculties ; and since our design, as already declared, is only to condemn those fashions which by producing deformities or otherwise, tend to shorten life, or produce disease, we should have nothing to say against the fashion of moulding the cranium into any form which the taste of the age might propose, if in- deed, no bad effects followed. 975. But if our female readers will examine the trunk of the human skeleton, represented at Fig. 95, and ob- serve in what manner the five lower ribs are attached, and how readily, in the young subject especially, they would so yield to the force of a tight band, as greatly to diminish the cavity they were intended to maintain, and also remember that this cavity contains the vital organs, the heart and lungs, neither of which will endure pressure with impunity, we think, that on contrasting this with Fig. 137, they can hardly avoid the conclusion, that other sad consequences must follow the use of tight lacing be- side the deformities we have described. EFFECTS OF TIGHT LACING. 305 976. It is shown by Fig. 96, and its description, that the lungs are always in contact with the diaphragm, and that they completely fill the cavity of the chest on each side of the heart ; this cavity cannot therefore be dimin- ished, without exerting a direct pressure on the organs of respiration. 977. It is further shown, p. 152, that the lungs are composed of a tissue of blood and air vessels, of such ex- treme tenuity, that the latter have been computed to amount to nearly two hundred millions in number, forming a surface of many hundred feet in extent ; and that the blood-vessels are equally numerous, presenting a surface similarly extensive. And however incredible it may ap- pear, the whole extent of these two surfaces, thus present- ed to each other, and by means of which, a vital process is effected, without which we could not live a moment, is still contained within the narrow spaces occupied by the lungs ; each of which do not exceed a foot in one direc- tion, and six or eight inches in the other. 978. Now who believes, that organs so " wonderfully and fearfully made," — so frail and delicate in their struc- ture, as to present tissues of circulating vessels scarcely exceeding a spider's web in size, will permit such an abuse, as to be compressed into one third, or even one half their natural dimensions, without some punitive inflic- tion on those who have the temerity to offer such violence to nature. 979. The first effect produced by compressing the lungs, will be a want of due oxygenation of the blood ; because many of these minute vessels must thereby be closed against the admission both of the air and the circulating* fluid. 980. By a reference to the article " Circulation," p. 130, it may be seen that in the amphibia, only one half of the blood circulates through the lungs ; and that in the fishes, there is no aorta by which it is carried to the different parts of the system as in other animals. The quantity of blood in the latter is also exceedingly small, when compared with that of other animals of the same size. In the amphibious animals, therefore, the circulating fluid consists of one half arterial, and the other half venous blood ; and on this account, these tribes are cold-blooded, 26* 306 APPENDIX. torpid, and almost without feeling. In the fishes, the small quantity of the circulating fluid, the want of an aorta to give it velocity to the different parts of the body, and the minute quantity of air the water contains ; all con- spire to keep the temperature of these animals down to that of the element in which they live, and to give their flesh a pallid hue, so different from the florid complexion of that of the mammalia. 981. It is true that the organization of these animals, is undoubtedly well fitted to their conditions, and the places they were intended to occupy in the scale of crea- tion. But we find, as we rise in this scale, that the or- gans of animals become more perfect, and that in the mammalia, and man, the respiratory apparatus is so com- plete, as to expose the whole mass of blood to the influ- ence of the atmosphere ; and that the circulating system is such as to propel the vital fluid with great force and rapidity, to every part of the frame ; and hence it is, that these animals differ so materially from those in which the respiratory function is less perfect, and the circulation less rapid and vigorous. In the former we find a temperature of 98° or 100° at all seasons, instead of a deathlike cold- ness ; and a high degree of vigor and vivacity, with a red muscular fibre, instead of torpor, insensibility, and white flesh, as in the latter. 982. Now if these very remarkable differences are in any considerable degree dependant on the quantity of oxy- gen, which the different races consume by the process of respiration, and which the facts we have detailed would seem to prove beyond all doubt ; then is it not as clear, that by compressing the lungs so as to prevent the or- dinary supply of oxygen in respiration, that the vigor of the circulation, which depends on that process, must grad- ually be diminished ; and that paleness, torpor, listless- ness, arid gradual emaciation, from poverty of the blood, and a consequent want of a healthy secretion, must be the consequence ? 983. It is quite certain that all these consequences, in very numerous instances, follow excessive lacing in young females ; and from the hurried, and laborious respiration, which those exhibit who are undergoing the process of being moulded into a fashionable form, there cannot be EFFECTS OF TIGHT LACING. 30" a doubt but the aeration of the blood is defective , and hence the necessity of the quick and unnatural inspira- tions, in order to maintain the circulation, which would cease the moment the air ceased to act upon it. These devotees, beside betraying their sufferings by a quick- ened respiration, show also by the livid color of the lips, that the blood is not sufficiently decarbonized, or is not completely changed from the dark venous, to the light arterial. (See p. 153.) 984. It cannot be supposed by those who will reflect upon this subject, that the laws of the animal economy can be thus disregarded for any considerable length of time, without inducing the most disastrous consequences to the general health and constitution. Every one knows that air is the pabulum of life, and that a free, pure atmo- sphere is absolutely necessary for vital and muscular energy. Whoever, therefore, interrupts the free ingress of air to the lungs, beside the injury which will follow to the organs themselves, does the same, in effect, as to create a vitiated atmosphere for her own use ; since in both cases, a full supply of oxygen is equally wanting, and in both, the consequences are the same. 985. Those, therefore, who create by stays, corsets, or otherwise, such a continual pressure on the lungs as to interfere with their regular and appropriate functions, may expect sooner or later, to suffer either sudden death by apoplexy, disability by palsy, or at least a gradual decay of the constitution, attended with fetid breath, af- fections of the lungs, liver, or other viscera, and which will terminate in the prostration, and final extinction of all the powers of life. 986. Pulmonary Consumption in consequence of Pres- sure on the Lungs. — It is most probable that when a de- gree of pressure is made on the lungs sufficient to bring the fine tissue of vessels, of which they are composed, into such a state of collapse, as to prevent the ingress of air, and the circulation of the vital fluid, that the portions so pressed suffer a slight degree of inflammation, in con- sequence of which, they adhere into masses, more or less solid, thus closing them entirely, and preventing ever afterward, though the pressure may be removed, the full 308 APPENDIX. and healthful aeration of the blood. From this cause, there would arise all the consequences which come from living in a vitiated atmosphere, or from breathing air which contains, perhaps, only one half the usual quanti- ty of oxygen, as above explained. In such cases, it is possible that no other effect on the lungs themselves may follow ; the subject gradually declining from general debility, and such poverty of the blood as to allow of no healthy secretions, and thus sink down to the grave without the usual symptoms of pulmonary consumption. Such may be said literally, " to die for want of breath;" not however, stopped by " the destroying" but the self- destroying angel, if indeed angels ever assist on such oc- casions. 987. It is perhaps singular, that this state of the lungs often betrays itself by an offensive breath, without ulcer- ation, or designed infliction, perhaps, on those who thus violate nature's laws. But if nature is sometimes slow in resenting and avenging the insults offered her, and al- lows some to live on her for years who habitually violate her laws, others are brought to speedy account for such temerity ; for it is well known that blood-spitting, hectic fever, and finally all the concomitants of consumption of the lungs follow excessive lacing, and many of which terminate in a short period. Healthy females, who have no family predisposition, and who begin this practice late in life, as from eighteen to twenty, are not so apt to suf- fer as those who have such a predisposition, and are laced from their childhood. 988. In the former however, the most pernicious con- sequences sometimes follow, as where a fine healthy country-girl, who never had been laced, happens to visit her fashionable cousins in town ; and who of course, will not be seen in the streets with her, in such a countrified shape. The poor girl must, therefore, be literally screwed into the city form, before she is allowed to " see company," and having perhaps a capacious chest, such as nature formed, and this being composed of a bony framework, it is impossible to bring it within the compass of the fashionable mould, without lapping the ends of the ribs either over or under the breast-bone. EFFECTS OF TIGHT LACING. 309 989. This effect follows in numerous instances, attend- ed with a hard projection on one side of the breast-bone, and a hollow on the other ; or the bone itself in other instances, has one of the edges thrown outward and the other turned inward, consequently because the lungs, as already shown, entirely fill the cavity of the chest, one or both of the lobes, beside the general pressure, must suffer a local injury from the interior protuberance thus formed. 990. More than one instance of this effect from exces- sive lacing, has come within the knowledge of the author ; and more than one who reads these observations will ac- knowledge perhaps mentally, the truth of the statements here made, and will be able to bring examples either in themselves or their friends. 991. Dr. Morton' 's Case, proving the above Assertions. — But since many profess to doubt the injurious consequen- ces of tight-lacing on the lungs, at least so far as them- selves are concerned, we will here offer an abstract of a case for the consideration of such ; and which we cannot but hope will be thought worthy of serious notice by our female readers. It is from a work on consumption, by Dr. Morton, of Philadelphia. 992. " A lady," says he, " aged thirty-two years, of strong constitution, and good frame, but of a nervous tem- perament, with dark hair, and brunett complexion, had been for some time under the care of Dr. Hodge, for an attack of severe nervous irritation ; when in the absence of that gentleman, I was requested to see her on the 6th of May, 1833. On my arrival, I found her dying, and she survived but a few hours. 993. " There was no obvious emaciation, but the thorax was contracted by a depression of the breast-bone, so as to reduce the diameter between it and the spine. On removing the pectoral muscles, the five or six superior ribs were observed to be considerably depressed at their extremities, where the cartilages joined them to the ster- num, and at which point there was a remarkable angle which protruded into the thorax. The left lung adhered at its apex, at which point the pleura [the membrane covering the interior of the ribs], was deeply contracted 310 APPENDIX. or puckered. Within was observed a rounded white mass, about an inch in diameter, composed of little grains of a cartilaginous firmness : this was obviously a cicatrized [healed] abscess, and in its centre were two or three crude tubercles [the commencement of suppura- tive ulcers]. The remainder of the lung was perfectly healthy. 994. " The right lung, like the left, adhered at the apex, where the pleura was also deeply sunk, and puckered ; beneath one of these plications was the remains of an old, but very small abscess, half filled with granular matter, like that in the other lung, excepting that it was of a darker color : the remainder of the abscess was in a sup- purative state, and contained yellow matter. Close by were the evidences of a second cavity, of the size of a fil- bert, but perfectly filled, and consolidated by white granu- lar matter, precisely like that of the left lung. The other parts were healthy. 995. " The unexpected morbid appearances of the lungs," says Dr. Morton, " induced me to inquire into the previous history of the patient, when I was informed by a near relative, that in early life she had habituated herself to excessive tight lacing ; but although she had never ex- perienced any obvious ill effects from this practice, she had of late years discontinued the practice, from a conviction of its injurious tendency. 996. " It seems probable, therefore," he continues, " all circumstances considered, that the lungs became tubercu- lous and cavernous from the irritation of mechanica* pressure ; but on the latter being removed, the morbid secretion ceased, and the cavities became cicatrized and obliterated in the manner just mentioned. Can there be a doubt that if this lady had persisted in the unnatural confinement of her respiratory organs, the tuberculous dis- ease would have extended, the abscesses enlarged, and the disease become a fatal malady ? The predisposition to phthisis [consumption] being slight, it was suspended by the removal of the exciting mechanical cause ; show- ing what important results physical education may pro- duce on the human frame."* •Illustrations of Consumption, by Samuel George Morton, M. P., &o., &c., pp. 99. Key & Biddle, Philadelphia, 1834. EFFECTS OF TIGHT LACING. 311 997 Says Dr. Reid, " very straight lacing, and strain- ing for a fine shape, hath made many a fine girl spit blood, and ruined the lungs by preventing a full and free respi- ration." On Consumption, p. 99. 998. Now since the practice of tight lacing, if not universal, is at least exceedingly common, and as the re- mains of comparatively few who die of diseases of the lungs are submitted to post-mortem examination, it is im- possible to give any conjecture of the number who destroy themselves in this way. But I have no doubt that the ladies themselves, to a considerable extent, will agree with me in believing, that hundreds, nay thousands^ of females literally kill themselves every year by this fashion in our own country : and if suicide is a crime, how will such escape in the day of Jinal account ! 999. We have represented by figures 134 and 135 the difference between a natural human skeleton, and one in Fig. 134. Fig. 135. which the pressure of stays has pushed the front ends of the ribs inward, bending the soft cartilages, so as to make them form acute angles outward. It will be obvi- ous to those who will reflect on this subject, even only for a moment, that the ribs cannot possibly sustain the force often applied to them in the process of forming a slim waist, in a girl of eighteen, without yielding in one direction or another; otherwise, and if the circumfer- ence remained the same, no difference would be made in the size of the chest, except that resulting from the compression of the fleshy fibres by which it is covered ; •312 APPENDIX. and this certainly is not sufficient to account for the effects actually produced. If we undertake to diminish the circumference of a hoop, we shall find it impossible to do so, without having the ends where the circle is joined shoot by, or lap over each other. The lower ribs, the cartilages of which join the breast-bone obliquely, leaving a space between their ends, may be pressed so as to diminish the circumference, by forcing these parts inward upon the lungs, without producing this effect; but the upper ribs which are continued directly forward to the breast-bone, by their cartilages, cannot have their circumferences shortened without doubling these parts upon their ends. The consequence of this will be, that these ends, on one side or the other, must project inward upon the lungs, as shown in the case dissected by Dr Morton, and stated above. 1000. The diminution of capacity in Fig. 135, when compared with 134, is not nearly so great as wre believe actually takes place in many instances of tight lacing the figure being made to show the displacement of parts in the skeleton, by that process, rather than the extent of its effects. MORTALITY OF CONSUMPTIVE DISEASES. 1001. In Great Britain it is estimated that 50,OuO per- sons die annually of consumption. 1002. In the city of New York, the whole number of deaths of all ages and diseases, in five years, namely, from the beginning of 1829 to the end of 1834, was 31,822, making a yearly average of 6364. 1003. Now it is known by the reports of the inspector, that nearly one in five of the mortality of that city, are of consumption, in one form or another, which give the number of 1272 per year, who die of this disease, in that city alone. The cities of Philadelphia, Baltimore, and Boston, present similar bills of mortality from the same cause ; and these bills also show that much the largest proportion of these are females. But there is no reason to believe that females are, from their organization, any more predisposed to consumption than the males. How then shall we account for the difference of mortality PREVENTION OF SPINAL DISTORTION. 313 from the disease, but by attributing it to a mode of dress, which no one will deny, does in many instances at least, not only create such a predisposition, but actually and obviously brings on the disease ; and from which the males, even of the same families, escape, by using a dress which allows the functions of the lungs to be continued agreeably to the laws of natural economy, and the design of the Creator. PREVENTION OF SPINAL DISTORTION. 1004. It is no part of the plan of this work to point out the methods of cure proposed, and practised by sur- geons and physicians, for the various deformities and other affections in young females, consequent upon the causes which have been noticed in the foregoing pages. And yet, we can hardly avoid saying a few words on this subject for the purpose of showing young ladies what terrible remedies are employed for these deformities, and how difficult it is to cure them, even in their incipient stages. This we do as a warning to those who are still in the enjoyment of their natural forms, not to make use of any of the means, or indulge themselves in any of the habits which we have described as the causes of such evils. And also, a caution to mothers, how they encour- age their young daughters in tight lacing for the sake of procuring genteel forms, lest thereby they should thus be- come the authors of disgusting diseases which art can never remedy, instead of the fine shapes which they ex- pect will be so much admired and coveted. 1005. The attempts heretofore most commonly made to cure curved spines have been by means of various machines, consisting of beams, bars, pulleys, ropes, screws, inclined planes, straps and buckles, more or less of which are combined, and applied in different ways, according to the nature of the case, or the skill of the mechanic by whom these machines are employed. 1006. The late Mr. Shaw, a surgeon of reputation in London, who has written a treatise on the cure of curved spines, says that it is the practice of some to keep young girls afflicted with this disease in a horizontal position, for months, and even for years, " without intermission." 27 314 APPENDIX. 1007. Stretching machines are also employed, which, by means of straps passing under the chin, and around the back of the head, keep the spine in a continued state of tension. Nearly the whole weight of the body is suspended by the straps, and thus are often used, until the chin becomes ulcerated and the countenance perfectly deformed, in consequence of their pressure on these parts. 1008. Another invention for the same purpose consists of complicated machinery fitted to the back, and which the miserable sufferer is doomed constantly to wrear. With respect to one of these, Mr. Shaw says, " I could not have believed (had I not seen the fact) that with the most determined resolution to endure pain, any person would have submitted to the punishment of carrying such a machine on the back for twelve months." 1009. Of the stretching chair, another apparatus for "straightening young spines, Mr. Shaw says, " The wind- lass by which the crane is elevated, and to which the patient's head is proposed to be attached, is so powerful that it might almost tear the head from the body." 1010. For the same purpose the rope and pulley is not only used, so as to raise the patient from the ground by the chin, but to keep them thus suspended for some time. " Until," says Mr. Shaw, " I saw several patients under- go this experiment, I could not believe that it was ever put into practice ; for it is quite obvious that while a child is suspended by the chin, the ligaments of the neck must be stretched to a dangerous degree." On examining girls who have been daily swung up for months, in this manner, the same writer found, that the muscles passing from the head to the neck, were so increased in size, as to make a new species of deformity. 1011. It ought, however, to be understood, that these are the methods employed by quacks and the irregular practitioners for the cure of distorted spines, and that most of them are condemned by well-educated physicians. In this country similar machines are made use of for the same purposes, and with what success the patients and their friends are the best judges. It is certain, however, that the patient as well as her friends, are often deceived by an apparent cure, when the disease and distortion are PREVENTION OF SPINAL DISTORTION. 315 only confirmed and increased by this kind of treatment. The spine, it is true, may be stretched into shape by screws and pulleys, but if the muscles of the back are pressed, or their action superseded by the machinery, the cure will be found to last no longer than the machine is employed, and when this is removed the curvature will gradually return, and probably become worse than before, because the muscles by inaction are still less able to sup- port it in the erect position than when such treatment commenced. 1012. A variety of other machines beside those above mentioned, have been invented and are employed for the same purpose, both in Europe and in our own country. One of these is constructed for the express purpose of forcing the vertebrse into their places, under the mistaken notion that in certain cases of distorted spines these bones are dislocated. There is no doubt but many a sufferer from spinal distortion, through the ignorance of herself, her family, and of the practitioner, have fallen disabled victims to the use of these machines. But perhaps enough has been said on this subject. 1013. It is not pretended that want of exercise, im- proper postures in sitting, and the use of excessive la- cing, are the sole causes of spinal distortions. On the contrary, these affections are sometimes the consequences of diseases which probably no prudence or foresight on the part of the sufferer or her friends, could have avoided. But that the greatest proportion of these cases are owing to the causes assigned, those who "will examine the subject will not have the least doubt. 1014. Girls from their organization, are no more ob- noxious to these affections than boys, but with the excep- tion of rickets, to which both sexes are liable, we may look almost in vain for a case of spinal distortion among the latter. And besides, if we go into the country, where fashion allows nature, and not art, to mould the female form, and where the children of both sexes take nearly the same amount of the same kind of exercise, in the open air, there will be found but little difference in the number of spinal distortions in the two sexes, instances of either being comparatively rare. 1015. If then, parents and school teachers would avoid APPEN o 3 16 APPENDIX the evils in question, they must remember that the first and grand rule in physical education, is, or ought to be, never to interfere with, or disregard the laws of the ani- mal economy, in the treatment of their children, or pupils. 1016. We do not mean by this, that children and scholars are not to be placed under restraint, or that a proper and wholesome degree of discipline is unnecessary or improper. On the contrary, a full liberty of person and action during the buoyancy and inexperience of youth, would lead to opposite consequences, more to be dreaded than the strictest discipline to which children have ever been subjected. But in no event should the discipline of children be such as to interfere with, or counteract the physiological functions of any portion of their growing systems. And we need not repeat here what we have already spent so many pages in showing, that young ani- mals have a natural propensity to muscular action, and without which, it is impossible they should make well- formed and healthy adults. 1017. Now the muscles of the spine, in common writh those of the other parts of th'e system, require almost constant exercise in the young, during their waking hours ; and not only so, their inaction, or unnatural contractions, as we have abundantly shown, are peculiarly liable to be attended with the most unfortunate consequences. The peculiar structure of this part being composed of alter- nate pieces of bone and cartilage, renders it peculiarly liable to grow out of shape in youth, for the reasons already assigned, and when once a distortion of this col- umn commences, it is exceedingly difficult to prevent its ruining the symmetry of the form, and still more so to bring it back to its original position. Distortions of this part, indeed, are often so insidious and gradual, that not a friend, nor even the subject herself is aware of it, until it has made such progress as to be apparent to a common observer. And it will perhaps astonish some of our readers to know that in our cities, probably one in six are thus deformed. 1018. To prevent distortions of the spine and shoulders in young females, it may be inferred from the physiological principles we have explained, and the facts we have ' PREVENTION OF SPINAL DISTORTION. 3 17 stated, that it is necessary, first, to avoid tight lacing ; second, to avoid improper positions at school, and certain modes of dress ; third, that the seats in the school-room should be provided with backs ; fourth, that the time usu- ally occupied in study at school, should be diminished ; and fifth, that the students should be allowed to take abundance of exhilarating exercise, such as nature requires in the open air. 1019. Every seat should be furnished with a back, not however with a narrow strip elevated so as to come across the shoulder blades; but a continuous support from the bench to the height of about two feet, and not standing perpendicularly, but curved a little backward. By such a back the spinal column is properly supported. 1020. School-rooms ought to be furnished with desks at which the pupils can write in the standing posture. These need not exceed one half or perhaps one third the number of pupils, and may be used in rotation. 1021. Four or five hours per day, spent in close study and recitations, is perhaps as much time as can be em- ployed to the mental and corporeal advantage of pupils from twelve to sixteen years of age. And young chil- dren ought not to be kept in their places more than an hour at a time, after which some little pleasant relaxation should be allowed, and in which the teachers should par- ticipate. 1022. Every school-house for young children should, if possible, have a play-ground, furnished with implements for amusement, adapted to their ages. And seminaries for young ladies should be provided with a romping yard, with a high fence, and a shed on one side, for exercise in bad weather. This should be furnished with bows and arrows, and such other instruments of exciting amusement as may be found most agreeable to the ages of the pupils ; and here they should be allowed to enjoy an hour, or half an hour, at proper intervals, several times during the day. 1023. If these suggestions are carried into general practice, we cannot but believe that the number of de- formed shoulders, crooked spines, pale faces, and con- sumptive diseases, would be greatly diminished among our females. 27* 318 APPENDIX. 1024. Effects of Stays on the Size, Vigor, and Health of our Species. — Beside the consequences ascribed to the uses of stays, in the foregoing pages, there is another effect to be noticed, which, so far as we know, has been en- tirely overlooked, or at least unnoticed, by writers on the subject of physical education ; but which the patriot and philanthropist cannot but consider as highly important. We mean the effects of tight lacing on our species in a national point -of view. 1025. It has been shown in the preceding pages, that when any portion of the animal system, and especially the soft parts, are pressed, nature sets herself to work, and because she cannot remove the offending cause, avenges herself of the insult, by removing through the absorbent system, the parts pressed upon, arid thus relieves herself of the injury. 1026. Now the glands, or organs which secrete the fluids peculiar to the several parts of the system, are particularly sensible to injuries of this kind ; and when they occur, nature evinces her resentment by a speedy reduction, or sometimes by the entire removal of the offended organ. -In case the gland happens to be one which nature intended should be prominent, the continu- ance of the pressure will either prevent its full develop- ment, or if already developed, will reduce it to the com- mon level of the surface where it is situated. These are well-known physiological facts, of which the physician in his practice, and the common observer in his observa- tions, have undoubtedly seen numerous instances. 1027. The class of animals called mammalia, as al- ready explained, receives its name from the presence of certain glands, called the lactescent, which are common to all the species, and which are designed to secrete suste- nance, for the continuance of the races to which they severally give existence ; and without such an organiza- tion, no tribe of animals can claim a place in the natural- history arrangement of this most important division of the animal kingdom. 1028. When this class was formed, the order called bimana, or two-handed, of which man is the only species, there was no want of those peculiar qualifications in our race, which constitute membership in it j but at the pres- EFFECTS .OF STAYS. 319 ent time, this order, at least in many parts of our coun try, has lost, in a lamentable degree, and in some speci- mens entirely, those marks by which its individuals once claimed a prominent rank among mammiferous animals. And if the use of stays, corsets, steel busks, and their adjuvants, continue to inflict their marks on future gener- ations, as they do on the present, the order bimana will undoubtedly deserve to lose its place in the mammalia class ; since there will issue an entire extinction of those natural organs, which form the chief characteristic of this class, and from which its name is derived. 1029. The loss of membership among the mammalia, it is true, is of little importance except to the naturalist ; but to the patriot, and moralist, the extinction of these prominent traits which once distinguished the gender of our species, cannot but create feelings of commiseration, and regret, since such a deformity not only involves a violation of the laws of nature and morality; the first by suppressing the growth of important parts of the animal system, and the second by the hazard of health and life as a consequence ; but it also inevitably leads to a dete- rioration of the species, with respect to stature, form, and constitution. 1030. It is true that stays are no recent invention, having been knowrn to the nations of Europe, before our fathers and mothers came to these shores ; and therefore it perhaps may be objected that the consequences we have attributed ta them, may with the same probability have happened formerly as now. But the construction of this article o£ dress, though called by the same name, is materially different from what it formerly was, as any one may convince herself by hunting up, and examining those worn by her grandmother. These will be found so constructed as not in the least to interfere with the expansion of the upper half of the bust; while those of the present day, it may be presumed from the forms moulded into them, are so made as either to present a barrier of whalebone, or steel, to an unequal expansion . of the parts which they encompass ; or if any such pro- vision is allowed, it must be rather in the region of the shoulder-blades, than in that of the anterior portion of the bust. 320 APPENDIX. 1031. The fact that the female form has undergone a very material change within the last 20 years, and that this change has been caused by the pressure of stays on parts of the system which are of the utmost importance to the nutrition, and consequent growth, and health of our species, cannot, and will not be denied by any competent witness. And that we shall become a stinted, puny, and short-lived race, in consequence, it requires no more in- spiration to predict, than it does to foretell that starvation will produce dwarfs in infancy, and emaciation in adults. 1032. The effects, indeed, are already visible in the number of pale, dwarfish, and crooked children, which may be seen in the schools and streets of all our cities, and many of our smaller towns and villages. And whoever, having been interested in the welfare of the rising gener- ation, will contrast, so far as she can recollect, the aspect of a school composed of both sexes, at the present day, with the appearance of the same number and ages, 15 or 20 years ago, cannot, we think, but be convinced, that that there has been a great deterioration in our youth, both in respect to form,, size, and healthy looks. 1033. And who, we inquire, would not expect to see such a change in our race, when they behold such a meta- Fig. 136. Fig. 137. Venus de Medicis. A Modern Lady. morphosis in the better half of our species, as to hnvi? produced from a stock like that represented by Fig. 136, EFFECTS OF STAYS. a progeny like that shown by Fig. 137. In the first, the parts which are essential to the nutrition and growth of incipient respiratory beings, are so developed as to insure a full supply of lactescent secretion ; while in the second, the corresponding parts present a mere pre- tence, a nullity, a source of starvation, rather than one of sustenance, to the nascent beings, who are so unfortu- nate as to be thrown upon such cotton and wool resources of existence. 1034. But what possible motive could have induced the females of the present age, and especially those of these United States (where ultraism in respect to this de- formity is carried to a much greater extent than in any other country), what, we ask, could have moved those among us, who have the first care of the species, and who ought to be our examples in moral rectitude and conser- vative discretion, to have thus deprived themselves of the power of fulfilling one of the very first of nature's laws ? 1035. Can it be for the purpose of making themselves more agreeable, and more acceptable to the lords of crea- tion 1 Then certainly their motives ought to meet with the law of kindness, and the tortures through which they are willing to pass in order to arrive at perfection — the sympathy and commiseration of those for whom such perils are encountered. But whatever motives might have led to a deformity so unnatural, it is certain that the Crea- tor intended, that the " noblest work of his hands," should possess the most perfect forms ; and therefore, except to a depraved and vitiated taste, such forms will ever be most admired, and most acceptable to those for whom they were designed. 1036. It is true that there are parts of our country where the practice of excessive lacing, and therefore its degenerating consequences do not exist ; and whence we are happy to know that many of the daughters of unsophisticated nature are transplanted into our cities, there to become the fostering angels of a renovated species. And were it not that such resources still remain, the consequences of fashion in all our cities would have been by far more degenerating than they are at present. Indeed we cannot but believe, were our large towns APPENDIX. walled, and their inhabitants under the necessity of depending on each other for the continuance of our spe- cies, that, under the dominion of the present code of fashions, the human race within their walls would finally, not only become perfect Lilliputians in size and mind, but that they would be known to future ages only as a fossil race, the types of which would nowhere be found on our earth in the recent state. But we must at present leave this subject, we hope, to resume it again in a trea- tise more particularly directed to mothers ; and contain- ing a detail of facts and circumstances, calculated to enlighten the minds, and touch the feelings of those who have the welfare of their country and their species at heart. •- . ' '*» APPENDIX B. HUMAN ANATOMY, GENERAL VIEW OF THE HUMAN SYSTEM. IN this synopsis of Human Anatomy, we propose to give a view of the whole subject, and then describe and illustrate such particular parts as will be most useful and intelligible to the student or general reader. Human anatomy is subdivided into descriptive, and morbid or pathological. Descriptive anatomy embraces a description of the different organs of the system, together with their rela- tive situations and connections ; it determines the text- ures of which they are formed, enumerates the nerves and blood-vessels by which they are supplied, and gives general and particular details concerning their organiza- tions. Having done this, descriptive anatomy proceeds to point out the analogies that subsist among the materials of which the several organs are composed, and is thus led to specify the several constituents of the human body. Morbid or Pathological anatomy comprehends the description of the effects of disease on the healthy struct- ures, and points out the changes of texture, and of com- position and appearance, which they have suffered in con- sequence of morbid action. Description of the different Parts and Organs of which the Human Body is composed. — -Anatomical writers first direct the student's attention to that branch of the subject termed Osteology, which means a de- How is anatomy subdivided ? What is descriptive anatomy ? What is morbid anatomy ? What branch of anatomy is first studied ? What is meant by osteology ? 324 APPENDIX. scription of the bones, or skeleton. These constitute the hardest and most enduring portion of the animal system, and on which its form and stability depend. In very young animals the bones are, comparatively, soft and yielding, so that many of them may be forced out of their usual forms by slight causes. As the an- imal advances to the adult state, these parts assume a a more solid form, and from a flexible consistence be- come rigid, and many of them even brittle. In contemplating this bony skeleton, when it has be- come perfect and fitted for the support of the whole fab- * ric, and the actions of the muscles with which it is every where surrounded, we can not but be struck with the ad- mirable adaptation, and the mutually befitting connection of which its various parts consist. The number of bones in the whole frame amount to about 250, including the teeth. Many of these are connected by surfaces which mutually correspond to each other, as the thigh bone, which has a round head, most perfectly fitted into a semi- spherical socket, having, therefore, free motion in every direction. Others, as the knee-joint, have grooves in the two opposite ends of the bones filling each other, and, therefore, have motion only in two directions. In others, as in the shoulder-blade, and the ribs, the motion is quite limited, there being no proper joint by which it can be effected. Articulation. — All the bones are connected with each other by what anatomists call articulation. Where motion is required, the evils of friction between the two surfaces are perfectly provided for by the peculiarity of each articulation, the two ends of the bones being cov- ered by soft, elastic cushions, composed of a substance called cartilage, the whole being lubricated by a gelati- nous substance called synovia, which here performs a ser- vice exactlylike thatof oil amongthe wheels of machinery. But as the bones must be more or less restricted in their range of motion, there must be some peculiar means by What is said of the changes of hones from the young to the adult state? What is said of the adaptation of the bones in forming joints ? What is ar- ticulation ? What is cartilage ? What is synovia ? HUMAN ANATOMY. 326 which that end is attained : some being prevented from changing their relative situations by certain modes of articulation ; others, where only a slight motion is re- quired, being united by cartilage ; and others, where extensive and varied motions are wanted, as in the shoul- der and hip joints, being connected by ligaments, mem- branes, and muscles. Ligaments. — Ligaments are white, fibrous, tough, glistening, and flexible expansions, or cords, which occur almost every where in the system, and, therefore, assum- ing a great variety of forms and sizes. They are, for the most part, exterior to the joints, and by their great strength and small elasticity, preserve the relative posi- tion or connection of the bones in their various move- ments. Membranes. — Membranes are thin, whitish webs, or textures, more flexible and elastic than ligaments, and, generally, of a more delicate fabric. They not only as- sist in the security and motion of the joints, but fulfill a variety of other offices. They surround, or line the cav- ities and the organs of the system, and contribute to unite and combine the whole ; and, at the same time, interpose and preserve a distinction between separate parts, thus enabling them to act independently of each other. They vary in strength, texture, and color, and thus different terms are applied to them in different parts of the body : two within the skull are called maters ; as, pia and dura mater : those which envelop muscular fibres are called aponeurosis ; that which covers the lungs, and lines the cavity of the chest, is termed the pleura; that which lines the cavity of the abdomen, and its included viscera, is called the peritoneum ; those which inclose the artic- ulated surfaces are termed capsules ; while those cover- ing the bones are the periosteum. In some other cases the membranes are named tunics, or coats. By what different means are the hones united ? What are ligaments ? What the uses of ligaments ? What are membranes ? Where are membranes found ? What are those within the brain called ? What is an aponeurosis ? What is the periosteum ? What is the peritoneum ? 28 326 APPENDIX. Flesh. — The remaining substance concerned in the connection of the bones is the flesh, or muscular fibres. It is by this means that the upper, as well as the lower extremities, are chiefly connected with the trunk, or body; these parts requiring great strength, as well as general motion, it being by means of the muscles that all the motions of the system are carried on. Tendons. — Many of the muscles contain, besides flesh, a substance analogous to ligament, through the medium of which they are attached to the bones, which are termed tendons. In most instances the muscles and tendons gradually replace each other, the thick part, being red flesh, gradually terminating in cords of shining white ten- don, the extremity of which is attached to a movable bone. The tendon of the heel, and the muscle of the calf of the leg, is a good example. Muscles and tendons are composed of bundles of fibres, which may be unraveled to extreme minuteness, when what appears to the naked eye as a single fibre, when placed under the microscope appears like a chain of infi- nitely small globular particles. Nerves. — But though the muscles are the immediate organs of motion, they are dependent for their powers of contraction and relaxation upon the nerves, with which they are every where numerously supplied. The nerves, when examined by themselves, appear in the form of white inelastic cords, or threads ; and, when traced to their ori- gin, are found to issue from the brain, or spinal marrow, the latter being considered an elongation or continuation to the former through the spinal canal. The trunks of the nerves are subdivided into branches, and these, again, into filaments not larger than hairs, which enter into the muscles and all other parts having sensation, being, as it were, lost in their substance ; that is, they become too minute for detection by the senses, though, in every case By what means are the limbs chiefly connected to the trunk? What are the tendons ? Where are the tendons attached ? What are muscles and tendons composed of? By what power do the muscles act? From what parts do the nerves issue ? What are the nerves the organs of? OF THE BLOOD AND ITS VESSELS. 327 where there is sensation or feeling, nerves are supposed to be present. The functions of the nerves, producing muscular motion, are sometimes independent of the will, as in the beating of the heart, and in others obedient thereto, as in the action of the locomotive muscles, ex- ercised in walking, or in the use of the arms and hands. That the action of the muscles, as well .as every spe- cies of sensation, depends on the nerves, is proved by the fact that all such phenomena cease, when the nerve supplying any particular part is separated. Thus, when the nerve which passes to the arm is cut, that member no longer obeys the will ; and the sight is instantly destroyed if the optic nerve is severed ; and so of every other portion of the system. The nervous trunks, which issue in pairs from the brain and spinal cord, amount to about 40 in number; and in tracing them and their branches, they are found in certain parts of the system to swell into knots called ganglia, a figure and descrip- tion of which will be seen at page 158. OF THE BLOOD AND ITS VESSELS. Having thus shown how the bones are connected and put into motion, and from what source their motion is derived, we- will next point out the means by which the muscles, as well as other parts of the living system, grow, and are nourished. The circulation of the blood, together with the extra- ordinary effects which respiration has on that fluid, have already been described severally at pages 127 and 163. Without this exposure to the air in the lungs, the blood is unfit for the purposes of life, nor can any animal exist more than a few minutes without it, strangulation being the speedy consequence. The heart is therefore so con- structed as to propel the blood which it receives through" the substance of the lungs by means of the arteries, which are there intermixed with the air-vessels, and thus the blood undergoes, by the influence of the air we take Is muscular motion always dependent on the will ? How is it proved that sensation depends on the nerves ? How many pairs of nerves are there ? What are ganglia? APPENDIX. in from the atmosphere at every breath, that mysterious change which prepares it to nourish every part of the body. The arteries, which carry the blood from the heart to all parts of the system, are divided into an infinite number of ramifications ; and the branches from the same trunk are frequently found to unite in their course, so that when by any accident some are cut off or obstructed, the circula- tion is still carried on by the others : a wise provision for a most important purpose. As we have already explained under the article " Cir- culation" the blood is carried to every part of the body by the arteries, and again returned to the heart by the veins, it being this continued circulation by which the whole system is nourished and renovated, by the action of these vessels. Absorbents. — These constitute a distinct system of vessels, which take up or carry away such portions of the blood as are either not wanted for nourishment, or as are useless, and to be cast out of the system in a state of solution. These vessels are furnished with valves, like the veins, and terminate in a common trunk called the thoracic duct, wrhich pours its contents into a vein just before it terminates in the right auricle of the heart. This vein is called the subclavian, and the course of the chyle through this duct has already been explained at § 298, Fig. 74. Renovation and Decay. — From the above observations, it may be inferred that a system of deposition and removal is continually going on within the living system ; that the ramifications of the arterial system are constantly renovating the different organs, while the absorbents are as continually removing the worn-out materials thus de- posited. It would appear, also, that the absorbent system, strictly What vessels carry the blood to all parts of the body ? What vessels re- turn the blood to the heart? What are the absorbents? Where does the thoracic duct discharge its contents? \Vh:tt is said of the renovation and decay of the living system ? RENOVATION AND DECAY, 329 so called, performs the double part of absorption and ex- cretion, as occasion requires. Thus, the vessels of the skin are commonly considered as performing the function of excretion, constantly emitting more or less fluid in the form of perspiration, and this appears to be the result of their ordinary action. " But it is a fact well established by more recent observations, that when the amount of fluid in the body has, by disease or otherwise, been greatly reduced, absorption of water through the skin may take place to a considerable amount. Thus, there is a case recorded by Dr. Currie of a patient who had such an ob- struction between the mouth and the stomach, that no nutri- ment, either solid or fluid, could be conveyed to the organs of digestion ; and, yet, this person was supported for many weeks by immersing the body every day in a bath of milk and water. During this time his weight was not diminished, and it was calculated by Dr C. that from one to two pints of fluid must have been daily absorbed by the skin. The patient's thirst, which had been ex- ceedingly painful previously to the adoption of this plan, was removed by the bath, in which he experienced the most refreshing sensations. Another proof that the skin absorbs water copiously is, that it is well known that shipwrecked sailors, and others, who are suffering from thirst, owing to the want of fresh water, find it greatly alleviated, or altogether relieved, by dipping their clothes into the sea, and putting them on while still wet. Even the moisture ordinarily contained in the atmosphere may be so rapidly absorbed as seriously to increase the weight of the body ; and it would seem that a small quantity of fluid taken into the stomach, in certain conditions of the system, has the powder of exciting this action of the skin. Thus, Dr. Watson, in his Chemical Essays, mentions a case where a lad at Newmarket, having been almost starved, in order to reduce his weight to the proper stand- ard for a riding match, was found to have increased nearly thirty ounces within an hour, apparently by having drank a glass of wine, for he had taken nothing else ; and What is said of the absorbing powers of the skin ? What was Dr. Cur- rie's case illustrating the absorbent powers of the skin ? What proof is there that the skin absorbs moisture ? 28* 330 APPENDIX. Sir. G. Hill witnessed a parallel case, where a much greater increase of the weight of the body appeared to result from the drinking of a single cup of tea. Mastication and Digestion. — These have already been treated of at pages 106 and 112, and we shall proceed to describe more distinctly than has been done in the forego- ing treatise, the Anatomical structure of the human frame. The human body, it is known to all, is composed of solids and fluids, united in different proportions. The solids give form and consistence to the different parts, and are composed of bones, ligaments, muscles, ten- dons, nerves, and vessels containing various fluids. The fluids form the largest proportion of the body, and con- sist of blood, chyme, chyle, and all the secreted liquids, as sweat, saliva, bile, tears, &c. These are all con- tained in vessels, cells, cavities or reservoirs. It has been found, contrary to expectation, that when the fluids of the human body are separated from the sol- ids, their proportions are as eight to ten. Thus, a body weighing 100 Ibs. contains only 20 Ibs. of solid matter, the remaining 80 being composed of various fluids. This has been ascertained by an examination of human bodies found in a dried state in the sands of Arabia, where the extreme aridity of the atmosphere prevents decomposi- tion, and acts on dead animal matters only by the ab- sorption of their fluid particles ; thus leaving the solid parts in a perfect, though in greatly diminished propor- tions, in appearance. Division of the Subject. — Authors have divided the anatomy of the solids into several branches, and named them according to the parts of which they treat. These are, 1. Osteology. A description of the bones. 2. Syndesmology. A description of the ligaments. 3. Myology. A description of the muscles. What are the solids of the human frame '. Which form the largest portions of the body, the .solids or fluids ? How is it known that the fluids form the largest portions ? What are the proportions between the solids and fluids ? GENERAL VIEW OF THE SYSTEM. 331 4. Splanchnology. A description of the viscera. 5. Adenology. A description of the glands. 6. Angiology. A description of the vessels. 7. Neurology. A description of the nerves. 8. Dermology. A description of the skin. Explanations. — The solid parts of the living system are named organs, as the instruments by which the va- rious functions are performed. Thus, the muscles are the organs of locomotion, the eyes the organs of sight, and the heart and arteries those of the circulation. These solid parts of our fabric, when minutely exam- ined, are found to consist ultimately of layers of minute fibres, or filaments, varied in appearance and texture, ac- cording to the use and offices of the part which they compose. Tissues, or Textures. — Tissue is a web-like struc- ture, which constitutes the chief elementary parts of ani- mal bodies. Nearly all the soft parts of animals are made up of such tissues, or textures, which are either spread out into membranes, or collected into cords, or hollowed out into canals ; and by their diversity of com- bination, figure, and color, they originate all the modifi- cations of structure and functions which the different or- gans possess. According to Mr. Paxton, author of a Treatise on Hu- man Anatomy, the systems of texture may be placed in the following order : 1 . The Bony System. 2. The Cartilaginous System. 3. The Fibrous System. 4. The Muscular System. 5. The Vascular System. 6. The Nervous System. 7. The Mucous System. 8. The Serous System. What are the names of the divisions of the anatomy of the solids, and what do they signify ? What is meant by the organs of the body ? What are tis- sues, or textures, of animal bodies ? 332 APPENDIX. 9. The Glandular System 10. The Adipose System. 11. The Cellular System. 12. The Dermoid System In a treatise so entirely elementary as this is intended to be, a distinct account of each of these systems can not be expected, nor is this necessary for the design of this work, as it would comprehend a detailed system of the anatomy of the human body. A short explanation of what some few of these systems comprehend, will in- dicate to the pupil what is intended by the others, and so of the whole. The bony system of texture refers only to the interior, or cellular portions of the bones, and not to their exter- nal and solid parts, which do not consist of tissues. The cartilaginous system refers to that white, semi- hard substance called gristle, which is attached to the bones, and must be distinguished from the ligaments and tendons, the latter of which are attached to the muscles, while the former act as binders of the tendons. The vascular system includes the veins and arteries, as well as the vessels which transmit colorless fluids, as the chyle and tears. The dermoid system refers to the skin. The adipose system to the fat, &c. THE BONES, OR OSSEOUS SYSTEM. Osteology is a discourse, or treatise, on the bones. Anatomy, which includes an examination of all the in- struments of life, signifies to dissect, or cut up. Our present subject, therefore, only refers to a description of the frame-work, or hard parts of the animal system. Skeleton. — A complete assemblage of the dry bones of an animal is called a skeleton, which term means "to — , _ . What are the systems of texture enumerated ? To what does the bony texture refer? To what does the cartilaginous texture refer? To what does the vascular system refer ? What is the dermoid texture ? What the adi- pose texture ? THE BONES, OR OSSEOUS SYSTEM. 333 dry up." When the bones are held together by their own ligaments, it is called a natural skeleton; when joined by wires, it is an artificial skeleton. Ossification. — The formation of bone, which this term signifies, consists in the deposition of the phosphate of lime on the soft solids of animal bodies, by a natural process. The bones undergo many changes before they reach their entire hardness and strength. In the young animal they are rio harder than cartilage, as may be observed in the head of the infant. They gradually increase in con- sistence and strength until about the twentieth year, when the bones of our species are supposed to become perfect for all the purposes for which they were design- ed. At this period of life the bones are of full size, and of sufficient hardness to sustain the action of all the mus- cles. Besides the phosphate and carbonate of lime, they contain large quantities of animal matter, and hence they are not readily fractured. But in extreme age the earthy matter predominates, and the bones become brittle by the loss of their animal matter, and from this cause it is that fractures are occasioned by slight accidents in old per- sons. Eminences and Depressions of the Bones. — Many of the bones have eminences or projections, and some of them furrows, or depressions, which are known to anat- omists by certain names, and which, therefore, it is nec- essary for the student to know. Eminences are called heads when they are convex, or roundish, and smooth on the surface, as the head of the femur, or thigh bone, and the humerus, or arm bone. Condyle, which means a knuckle, is applied to the pro- jections on the lower ends of the femur and humerus. Tubercles, or tuberosities, are small prominences, as those near the heads of the os humeri. Spine, or spi- nous processes, literally thorn-like, are the projections At what age do the bones of man become perfect ? What is the composi- tion of the bones ? Why are the bones of old persons easily broken ? What are the condyles of the bones ? What are tubercles ? What are spines ? 334 APPENDIX. - on the vertebrae, or back-bone. Cristce, or crests, are long, sharp elevations, as the crista galli of the ethmoid, one of the bones of the head. Trochanter, whicH means to run or roll, is applied to two eminences situated on the upper part of the thigh bone. They are so named because to these parts are attached the large muscles by the action of which the limb is turned or moved. Depressions. — Some of the depressions in the bones are of considerable depth, while others are quite superfi- cial. That which receives the head of the thigh bone is the deepest, and is called the cotyloid cavity. Those in which the teeth are fixed are called alveoli, or sockets. Those which are more shallow are called glenoid, as the cavity in the scapula, or shoulder-blade, which receives the head of the humerus. PERIOSTEUM. Periosteum signifies around the bone, and is applied to the membrane which surrounds all the bones in every part of the skeleton, except when they are tipped with cartilage, and the teeth, which are protected by enamel. In infancy this covering is but slightly united to the bones, and is removed from them with facility ; but in the adult it adheres firmly, and in old age can not be de- tached. In the healthy state, the periosteum, like the bones, is without sensibility ; but when diseased, it becomes ex- ceedingly painful. This is a proof that it is furnished with nerves, though they are too minute to be demonstra- ted to the sight. It is this membrane which gives vitality to the bones, for when separated from them, their surfaces perish, and exfoliate. To it are also attached the tendons, ligaments, and muscles. What are the crista ? What are the trochanters ? What is the cotyloid cavity ? What are glenoid cavities ? What is the meaning of periosteum ? What the uses of this membrane ? THE BONES, OR OSSEOUS SYSTEM. 335 NUMBER OF BONES IN THE SKELETON. The human skeleton consists of about 252 bones, the number differing three or four in different persons. This is in consequence of the variable number of the sesa- moid bones, which are small seed-like accumulations found about the joints of the great toe and thumb. The following list, from Paxton, will show the- names and number of the bones in the head, trunk, and extrem- ities. It must be remembered that there are two corre- sponding sides to the skeleton, and hence one half of the numbers are on each side, except about the head, where only single ones occur. Hones of the Head, 55 in Number. English. Latin. Frontal bone, Os frontis, 1 Parietal bones, Ossa parietala, 2 Occipital, Os occipitis, 1 Temporal, Ossa temporum, 2 Sphenoidal, Os sphenoides, 1 Ethmoid, Os ethmoides, 1 Nasal, Ossa nasi, 2 Malar, Ossa malarum, 2 Upper jaw, Ossa maxillare superius, 2 Palate bones, Ossa palatina, 2 Inferior turbinated, Ossa turbinata, 2 Corner, partition of the nose, 1 Lower jaw, Os maxillare inferius, 1 Teeth, Dentes, 32 Tongue bone, Os hyoides. 1 Bones of the Ear, 8 in Number. Anvil, Ossa incudes, 2 Hammer, Ossa mallei, 2 Stirrup, Ossa stapedes, 2 Orbed bones, Ossa orbicularia. 2 What is the number of bones in the human skeleton ? What is the number of bones in the head ? What number in the ear ? 336 APPENDIX. Bones of the Trunk, 57 in Number. Back bone, Vertebrae, 24 Ribs, Costae, 24 Breast bone, Sternum, 1 Hip bones, Ossa innominata, 2 Rump bone, Os sacrum, 1 Coccygeal bones, Ossa coccygis. 4 Bones of the Upper Extremities, 68 in Number. Collar bones, Shoulder bones, Arm bones, Fore-arm bones, Wrist bones, Hand bones, Finger bones, Thumb bones, Sesamoid bones, Claviculae, Scapulae, Ossa humeri, Radii et ulnae, Ossa carpi, Ossa metacarpi, Phalanges digitorum Ossa pollicis, Ossa sesamoidea. 2 2 2 4 16 8 manus, 24 6 4 Bones of the Lower Extremities, 64 in Number. Thigh bones, Ossa femoris, 2 Knee-pans, Patellae, 2 Shin bones, Tibiae, 2 Leg bones, Fibulae, 2 Tarsal bones, Ossa tarsi, 14 Metatarsal bones, Ossa metatarsi, 10 Toe bones, Phalanges digitorum pedis, 28 Sesamoid bones, Ossa sesamoidea. 4 252 As our limits will not allow a particular description of each of these bones, it may be remarked that, with the exception of those of the head, nearly every reader will know by their names their places in the skeleton ; and What is the number of bones in the trunk ? What number in the upper apj lower extremities ? What is the whole number in the human skeleton ? SUTURES. 337 with respect to the interior ones of the skull, their forms and situations are expected to be known only to profess- ed anatomists. In describing the human frame, it is understood that the position is erect, hence by superior and inferior is meant the higher and lower portions of that position. By anterior and posterior is denoted the front and hinder portions of the body, and by lateral, the side. HUMAN SKELETON. Having introduced the subject of human anatomy, by such explanations and remarks as the student would seem to require, in order to understand what follows, we shall introduce on the succeeding page a front view of the skel- eton, with su ;h references as to make the names and sit- uations of its principal bones readily seen. SUTURES. Suture, from the Latin suo, to sew, a seam. It is applied to the junction of the bones of the cranium, by serrated lines like the stitches of a seam. They origin- ate thus : The radiated fibres of the bones in their growth approach each other, and the fibres of the one, entering the intervals of the fibres of the other, form the serrated lines of union in question. Fig. 1. 338 BONES. 339 Fig. 2. Represents a Front View of the male Skeleton. HEAD AND NECK. 7i, The ulna. a, The frontal bone. 0, The radius. b, The parietal bone. c, Orbit of the eye. d, The temporal bone. e, The lower jaw. f, Vertebrae of the neck. TRUNK. g, The left clavicle, or col- lar bone. h, The right scapula, or shoulder-blade. k, The lumbar vertebrae. /, The left ilium, or hip bone. m, The right ilium. UPPER EXTREMITY. t, The humerus, or arm bone. The sternum, or breast bone, on which the ribs meet, requires no reference. Fig. 1 represents the principal sutures seen from above. The coronal suture a, a, passes in nearly a trans- verse line across the front part of the skull, and joins the frontal bone a, a, with the parietal bones. The sagittal suture, or arrow-shaped, b, so named from ks being straight like an arrow, extends from the middle of the superior margin of the frontal, to the angle of the occipital bone. It joins the two parietal, or wall bones, which form the sides of the skull, along the cranium. The lambdoidal -suture, c, c, so named from its resem- blance to the Greek letter lambda, commences at the ter- mination of the sagittal suture, and extends on each side p, The wrist, or carpus. q, The metacarpus, or hand. r, The phalanges, or fin- gers. LOWER EXTREMITY. 5, The femur, or thigh bone. t, The patella, or knee-pan. u, The tibia, or large bone of the leg. v, The fibula, or small bone of the leg. w, The tarsus, or instep. x, The metatarsus, or bones of the foot. y, The phalanges of the toes What is the meaning of sutures ? bones do the coronal suture join ? What hones do the sagittal suture join ? suture join ? What are theossa rriquetra How do the sutures originate ? What Why is the sagittal suture so called ? ' What bones does the lambdoidal What the squamous suture ? 340 APPENDIX. Fig. 3. d- down to the base of the cranium. It joins the occipital, to the parietal bones, above, and the temporal bones below. There are two little bones marked d, d, called ossa triquetra, from their triangular shapes. They are familiarly known to anatomists by the name of Ossa Wormiana, from their being first described by Olaus Wormius. The squamous sutures e, e, is so named because the temporal bones overlap the parietal, like a scale. They are on each side of the head behind the ears. OS FEMORIS. THE THIGH BONE. There are some parts of the os femoris which cannot be seen, and explained as this bone is represented in the skeleton. We therefore give an ad- ditional figure of it here, with explana- tions. The head, a, Fig. 3, forms the greater part of a sphere. It articu- lates with the hip, and is the most perfect instance of the ball and socket joint in the system. For additional security, this joint, unlike any other, has a short ligament attached in the hollow b, and to the bottom of the cup in the hip bone. The neck, c, is the oblique space between the trochanter and head of the bone. The large process d, is the trochanter major, and e, the trochanter minor. The curved liney, extending from one trochanter to the other, is the linea quadrata, being the point where the muscle called the quadratus femoris is at- tached. The body of the bone g, has a long rough elevated line h, called the linea aspera. The outer condyle, i, is opposite to the inner condyle, k. The condyles have four articular at- tachments, two of which are marked by u, o, where the the tibia is attach- ed4 The recess p, affords a safe pas- OS INNOMINATA. 341 sage of the large vessels to the leg. There are nine- teen muscles attached to this bone, several of which are the most powerful in the body. OS INNOMINATA. The os innominata, or nameless bone, so called on ac- count of its irregular shape, is that to which the thigh bones are attached. It is composed of three bones, all of irregular forms, and in the adult, united into one. These are the ilium, or haunch bone, the ischium or hip bone, and the os pubis, or share bone. (See skeleton.) Fig. 4. Z- BONES OF THE FOOT- Fig. 4 represents the upper surface of the bones of the f< ot, which are twenty-six in number. The astragalus, where it is articulated with the tibia, arises above the other bones and is marked f. The os calcis or heel bone g. The three cuneiform, or wedge- shaped bones, e. The tarsal bones forming the instep d. The metatarsal bones, five in number, a, forming the upper and arched part of the foot. The phalanges or rows of bones forming the toes, b, c, and i, are three in number. The whole number of bones in the phalanges are fourteen, the great toe having only two, while the What is the os femoris ? Describe the several parts of this bone. What is the os innominata, and of what bones is it composed ? How many bones has the foot ? 29* 342 APPENDIX. others have three each. The bones of the foot, individ- ually resemble those of the hand, but they are larger and stronger, and being connected by less flexible ligaments, the motions of the foot are not so free as those of the hand. LIGAMENTS. Ligameritum, from the Latin, ligo, to bind. The lig- aments consist of bundles of fibres, of greater, or less thickness, and of a compact texture, which serve to con- nect the articular surfaces of the bones and cartilages ; and in some instances they protect the joints as a capsu- lar envelop. The ligaments, though white and glistening in appear- ance, yet are well supplied with blood vessels from those in their immediate vicinity. They possess but a small share of elasticity, and in their sound and healthy state, are nearly or quite destitute of sensibility, but in a dis- eased state they become exquisitely painful. Ligaments of the CARPUS, METACARPUS, and PHA- Fig, 5. MUSCULAR SYSTEM. 343 LANGES, or of the wrist, hand and fingers. — Our limits only allow examples of the different connecting parts ol the human frame, and we have chosen the wrist and hand as the most appropriate for our present purpose. Fig. 5 represents the palm of the right hand, and shows all the principal ligaments with which it is furnished, together with those of the wrist. First, the three upper bones of the wrist are connected together by inter- osseous ligaments placed in the intervals between the bones, which are severally called the scaphoid, the semi- lunar and cuneiform. These are shown by a, b, c, and d. The palmar ligament, c, is divided into three portions, and running across the upper portion of the hand, joins the dorsal ligament on the other side, thus binding the bones strongly together. Second. The superior transverse ligaments d, d, ex- tend across the upper extremities of the four metacarpal bones and are attached to each of them. The ligament g, connects the cuneiform, with the metacarpal bone of the little finger. Third. The inferior transverse ligaments e, e, present exactly the same arrangement as the above, and connect the inferior extremities of the four metacarpal bones with each other, but not so closely as at their upper ends, the ligament here allowing a greater freedom of motion. Fourth. The first phalanges, or rows of finger bones are attached to the metacarpal bones by loose, but strong capsular ligaments, embracing the anterior part of each articulation. The lateral ligaments /, /, on each side of the fingers are attached to slight depressions on the lower ends of the metacarpal bones, and into the condyles of the first phalanx. Similar ligaments to these attach the other finger bones to each other, and also those of the thumb. MUSCULAR SYSTEM. Musculus, in Greek, signifies a mouse, probably ap* plied to the flesh of animals, because it resembles a flayed mouse. We have already seen that tke organs of What are the carpus, metacarpus, and phalanges ? Describe the ligaments of the wrist and hand 344 APPENDIX. locomotion are the muscles, or flesh, by which the bones of all animals are surrounded. We copy the following definitions concerning the mus- cular system from Hoblyn's Dictionary of Medicine, a book which every student in the sciences should pos- sess. Muscle, an organ of motion, constituting the flesh of animals, and consisting of beaded, or cylindrical fibres, which are unbranched, and are arranged parallel to each other in fasciculi. In general, the name venter, or belly, is given to the middle portion of a muscle, while its ex- tremities are named the head and tail, or more commonly the origin and insertion. Hence the term diastricus, or two-bellied, triceps, or three-headed, &c. I. Properties of the Muscles. 1. Contractility, by which their fibres return to their former dimensions after being extended ; and, 2. Irritability, by which their fibres shorten on the application of a stimulus. II. Forms of the Muscles. 1 . The muscles, like the bones, may be divided into long, broad, and short; and each of these kinds may present muscles, either simple, or compound. 2. The simple, or those which have their fibres arranged in a similar, or parallel direction. They are in general bulging, that is, their transverse outline is more or less inflated in the middle. The simple muscles are some- times flat, as the sartorius. 3. The radiated, or those which have their fibres con- verging> like the radii of a circle, to their tendinous in- sertion, as the pectoralis, one of the muscles of the chest. 4. Ventriform, or belly-shaped, which have their cen- ter large, diminishing toward their tendons, or extremi- ties, as the biceps, or two-headed muscles. What is the meaning of the word muscle ? What are the muscles ? What are the properties of the muscles? What are the forms of the muscles? What is a simple mnscle ? ACTION OF THE MUSCLES. 345 5. The penniform, or pen-shaped, which have their fibres arranged obliquely on each side of the tendon, as the rectus femoris, a muscle of the thigh. 6. The semi-penniform, which have their fibres ar- ranged on one side of the tendon, as the peron&us longus, a muscle of the outside of the leg. 7. The complicated, or compound, which have two, or more tendons, as the flexors of the fingers ; or a variety in the insertion of oblique fibres into the tendons, as the linguales, muscles of the tongue. III. Action of the Muscles. 1 . The voluntary, or those which are subject to the will, as those of the legs and arms, or those of locomo- tion. 2. The involuntary, or those which act independently of the will, as those of the heart. 3. The mixed, or those which act imperceptibly, but yet are subject, more or less, to the control of the will, as the muscles of respiration. CONTRACTIBILITY OF THE MUSCLES. — We have al- ready given a definition of this property of the muscles ; but, as the agent of motion in the animal system, and the principal characteristic of these organs, some illustrations of this property ought to be stated. Contractibility, constituting muscular action, consists in the movement of the middle portions of the fibres to- ward the two ends, where they are fixed. Thus, in the amputation of a limb, as soon as the muscles are divided, the two portions contract toward their fixed ends, leaving a gap at the point of division, which is more or less wide, according to the length and power of the muscle. Every movable point in the solid animal frame is situated be- tween two muscular powers, acting in opposition to each other ; thus are produced flexion and extension, elevation and depression, abduction and adduction, all by the dif- ferent ways in which muscular contraction is exerted." What is a radiated muscle ? What a ventricose ? What a penniform ? What a semi-penniform? What a complicated? What are the voluntary muscles? What the involuntary? What the mixed? What does con- tractibility consist in ? 346 APPENDIX. In whatever direction the limb is to be moved, the movable point must necessarily be in the opposite direc- tion ; the act of flexion requiring that it should be first extended, and so the contrary. But when the flexors and extensors are both in a state of tension, they mu- tually counteract each other, and the limb is fixed. Every muscle, when it contracts, not only acts upon the bone to which it is attached, but also on the antago- nist, or opposite muscle, so that no one can act inde- pendently of the other. Dr. Paley, in his Natural Theology, gives the follow- ing familiar illustration of the action of the muscles : " Every muscle is provided with an adversary. They act like two sawyers in a pit, by an opposite pull ; the nature of the muscular fibre being what it is, the pur- poses of the animal could be answered by no other. And not only the capacity for motion, but the aspect, and symmetry of the body, is preserved by the muscles being thus marshaled according to this order : for exam- ple, the mouth is holden in the middle of the face, and its angles kept in a state of exact correspondency, by several muscles drawn against, and balancing each other. In hemiplegia [paralysis of one side], when the mus- cles of one side of the face are weakened, the muscles on the other side draw the mouth awry." Contraction increases the Hardness of the Muscle. — In lifting a weight with the hand, the arm being extended, the brachial muscle, situated between the elbow and shoulder, acts with much force, and may be felt to in- crease in size and hardness. This is the case with all the muscles, when in a state of action, and those which are most constantly employed, are increased in size and firmness in consequence of such continued action. Thus, the muscles of the right arms of blacksmiths are always larger, and possess greater strength and density than those of other men, in consequence of the continual employment of this limb in their business. How is muscular contractihility shown by amputation ? What is said of antagonist muscles ? What is the effect when antagonist muscles contract at the same time? What is Dr. Paley's illustration of the action of the muscles ? MUSCLES OF THE HUMAN BODY. 347 Nervous Influence. — The contractility, as well as the irritability, of the muscles, depend on the nervous influ- ence. Thus, if the brain is compressed, so that the will is destroyed, all action in the voluntary muscles ceases. The involuntary muscles, as those of the heart, and res- piration, may continue for a time, under such circum- stances, but the person lies as if in the arms of death, so far as the movement of the limbs is concerned ; and if this condition continues, and the nervous power, which depends on the action of the brain, is obstructed for a certain time, the heart ceases to act, and the respiration slops. Of course, if this state be continued for more than a few minutes, death must be the consequence ; but if the pressure from the brain be removed within a certain period, all the muscles of the system regain their wonted activity, and the person, as it were, comes to life, in consequence of the renewed action of the nervous power. Irritability is also the consequence of nervous influ- ence, but is not dependent on the will. Hence some of the muscles are *till irritable after the animal ceases to live. Thus, the muscles of criminals, after execution, are again set in motion by a galvanic shock, and the heart of a frog will continue to beat, on touching it with the point of a pin, for hours after it is separated from the animal. Having already illustrated the subject of muscular ac- tion at page 227 and onward, we shall here proceed to exhibit, and name the first layer of muscles of the hu- man frame, or those immediately under the skin. The total number of muscles is 527, of which 257 are in pairs, and lie on opposite sides of the body. Anterior View of the Muscles of the Human Body, Fig. 6. Observation. — Some of. the muscles extend from the anterior to the posterior portions of the body, so that, in the two positions here exhibited, a few of them have the same name. It is unnecessary to describe the situation of each muscle, as this will be seen on reference to the figures. 346 k MUSCLES OF THE HUMAN BODY. MUSCLES OF THE HUMAN BODY. 349 Anterior View of the Muscles of the Human Body, Fig. 6. a, The occipito-frontalis. &, The massater. c, The orbicularis oris. d, The depressor labii in- ferioris. e, The orbicularis palpe- brarum. /, The levator labii superi- oris. g, The zygomaticus major. h, The zygomaticus minor. i, The platisma myoides. j, The deltoid muscle. k, The pectoralis major. I, The latissimus dorsi. m, The biceps flexor cubiti. n, The triceps extensor cu- biti. p, The seratus major anti- cus. q, The obliquus abdominis externus. r, Transversalis abdominis. s, w, The pronator radii te- res. •t, x, The supinator radii longus. w, The tensor vaginae femo- ris. v, The extensor ossis met- acarpi-pollicis llfcinus. y, The psoas magnus. z, The sartorius, or tailor's muscle. #', The extensor carpi radi- alis longi or. b', f, The annular liga- ment. c', The palmaris brevis. d', The rectus femoris. e', The vastus externus. y, The vastus internus. g/, The extensor carpi radi- alis brevior. h^ The tendon patella. I', The gastrocnemius in- ternus. i', The triceps extensor crucis. mf, The tibialis anticus. The flexor pedis. digitorum What is the consequence of the continued action of the voluntary muscles ? On what does muscular action depend ? What is the effect of pressure on the brain ? 30 350 APPENDIX. Fig. 7. ft, MUSCLES OF THE HUMAN BODY. NERVOUS SYSTEM. 351 Posterior View of the Muscles, Fig.7. a, The occipito-frontalis. b, The massater. c, The complexus. d, The sterno-cleido-mas- toideus. e, The attolens auris. fj The attrahens auris. g, The trapezius. h, The deltoid muscle. i, The infra-spinat.us. j, The triceps extensor. k, o, The triceps extensor cubiti. I, The teres minor. m, The teres major. n, Portion of the triceps. p, The supinator radii lon- gus. q, The extensor carpi ulna- ris. r, s, The extensor commu- nis. t, The olecranon. u, The pronator radii teres. v, The extensor communis digitorum. w, The extensor ossis met- acarpi. x, The extensor communis digitorum. y The latissimus dorsi. z, The obliquus externus.