The principles of medicine

Front matter

Id t H.

DEPOSITED IN THE

BC:^jJliiDICALLlBIlAKX

Preface

Medical teaching has been very crude and imperfect, in practical medicine, from the want of a proper systemization of facts, and the development from these of pathological and therapeutic laws. In place of this we have been presented with the theories of closet practitioners, and the vagaries of dreamers, who were always more persistent in making known their views than the modest toiler by the bedside of the sick, in the dea'-room, or in the laboratory. There has, however, been a great change in this regard within the last quarter of a century; and men now value the facts of observation more than the conclusions arrived at by reasoning from imperfect data. Thus, the practice of medicine has attained such development that it may be regarded as a science.

Webster defines science to be "a collection of the general principles or leading truths relating to any subject, arranged in a systematic manner." In order, therefore, that the practice of medicine should be termed scientific, it is necessary that there be certain well-defined truths, and that these be so grouped together as to establish fixed principles.

Many deny that there is any science in the practice of medicine, and only admit it in chemistry and anatomy, out of the seven branches taught in our colleges. Others, and among these our best writers, while claiming that medicine is a science, almost entirely ignore it in practice, and in writing, results are given as almost entirely or quite empirical. That practical medicine is an art to be studied, and perfected by continued practice, must be admitted, but I claim that there is an underlying scientific basis that needs to be known to give the greatest success. The empiric may have success, but it is only after he has generalized his observations, and formed in his own mind, certain definite principles. The man who has this power in a great degree, has great success, while the vi Preface.

man who has it not, will not succeed. Any physician may prove the truth of these propositions hy looking into his own mind and tracing the process of reasoning by which his practice is governed.

If these are facts, and no person who looks at them dispassionately can doubt them, we can easily see the importance of the teaching of those generalizations of truths which form laws in practical medicine. Having mastered this, the student commences his practice with definite principles, and his observations being properly directed, his experience is more valuable. He commences, in fact, so far as regards this, at the point where the empiric would leave off after ten or twenty years practice. It is true that it is very difficult to get that thorough study from the medical student that will enable him to master the subject, and yet if presented in its simplest form, he will see a beauty in it that will excite to deeper study.

While I would ask the indulgence of the reader for many imperfections and short-comings in this volume, I am certain that he will find the facts correctly stated, and the conclusions legitimate; neither distorting the first from prejudice, or wresting the second to prove a favorite theory. The object has been to so generalize the facts of physiology and pathology, as to give a sound basis for a rational practice of medicine. If it serves this purpose, and gives efficient aid to the student in this difficult department of study, the author will be fully recompensed for his labor.

Table Of Contents

Page.

INTRODUCTION - 17-21

Definition of disease. Expressions of life in health. Symptoms. Study of disease. Excess, defect, and perversion. Anatysis of disease. Advantages of studying disease in this way. Author's classification. Classification of Dr. Williams.

Chapter I

Different opinions in regard to, 1. Dr. Draper on, 3. Organic life, 4. Swedenborg on vital force, 5. Stevens on life, 6. Carpenter on vital force, 7. Liebig on vital force, 8. Chambers on death and life, 9. Quotation from author, 10.

FORMATIVE FORCE - 32-38

Propositions in regard to, 11. Localization of, 13. Force an active condition, 14. Association with other forces, 15. This force not possessed by all persons in equal degree, 16. Conditions favoring formative force, 18. Means of determining its amount in an individual, 19, 20. That this force is not a fixed quantity with any individual, but may be increased and diminished, 21. Any agency that violently changes or affects any natural function impairs this force, 22. Agents that look to a better performance of the principal functions increase it, 23. Classification of such agents, 24. Comparison of the old and new practice, 25. Statistics, 25.

viii Contents.

Pago.

OF THE OTHER FORCES THAT GO TO MAKE UP THE SUM OF

VITAL POWER 39-46

Formative force but a part, 28. Heat, 29. Amount of combustible material, 30. Means of increasing heat, 33, 34, 35. Heat necessary to tissue formation, 36. A want of heat an clement of some chronic diseases, 37. Increase of temperature, 39. The function of the skin in removing heat, 41. Means of controlling the production of heat, 42, 43. Electricity — its production in the body, 44. Youmans on, 46. Carpenter on, 47. As a cause of disease, 48, 49. Remedial means, 50, 51. Od force, 52.

Chapter II

Virchow on, 55. The ultimate organic form, 56. Functions of cells, 57-60. Every function has its origin in cells, 61. Laws of cell-growth life and activity, 63. What is true of a part is true of the whole, 64. Illustration, 65. Early deviations from the normal type of development, 66. Conditions necessary to the development and growth of the entire organism, 69-71. Division of cells, 72. Formative, 73. Secreting, 74. Necrological, 75.

Chapter III

Food — histogenetic and calorifacient, 77. Deficiency of, 78. Standard of heat must be maintained, 79. Perversion of food, 80, 81. Selection of food, 82. Physiological table, 83. Difference between histogenetic and calorifacient food, 84. Food is valuable as it is easy of appropriation, 85. Quotation from Carpenter, 86.

A simple process, 87. To break up the organization of food, 88. Buccal, 91. Gastric, 92. Conditions of the stomach indicated by the tongue, 93. Intestinal digestion, 95. Observations of Prof. Busch.

Circulation with reference to nutrition, 97.

Innervation with reference to nutrition, 99.

Contents. ix

Pago.

HYPERTROPHY - 65-68

Conditions of, 100. Development dependent upon exercise, 101. The application of this law in practice, 102-104. Dr. Williams on Hypertrophy, 105.

ATROPHY 69-70

Causes of, 106. General, 107. Treatment of, 110. Partial, 111. Therapeutics of, 113.

PERVERTED NUTRITION 71-77

Degeneration — Definition of, 114. Causes of, 115. Fibrous degeneration, 118. Examples of, 119. Granular degeneration, 120. Virchow on, 121. Fatty degeneration, 122. Virchow on. Amyloid degeneration, 123. Osseous degeneration,. 124. Examples of, 125. Softening, 126. Diagnosis of degeneration, 128. Treatment, 129.

Classification of.

REPAIR OF INJURIES - - ------

Classification of, 132. Union by adhesion, or first intention, 133. Dr. Richardson on, 136. Union by cicatrization, 139. Reasons why new tissue is always fibrous, 140. Process of organization, 141. Formation of pus, 142. Tardy healing, 143. Origin of pus-cells, 144. Circumstances favoring the healing process, 146. Is inflammation necessary ? 148.

EUPLASTIC DEPOSITS ----_,--- 85-86 Definition of, 149. Fibroid organization in tissue, 150. Induration, 151. Contraction of such tissue, 152.

CACOPLASTIC DEPOSITS - 86-88

A lower organization, 153. Causes of, 154. Examples of, 155. Relation to tubercle, 158. Treatment, 160.

Definition of, 162. Causes of, 163. From want of vitality, 164. Hereditary, 165. Deposit depends upon local causes, 167. Analogy between scrofula and tuberculosis, 168. Characteristics of tubercular matter, 169. Treatment, 172.

x Contents.

Page.

MORBID GROWTHS 96-110

Definition of, 175. Analogous heterologous, 176. Non-malignant, 177 '. Note from Virchow. Size and development, 178. Injury to tissue by, 179. Treatment of, 180. Malignant growths, 182. Cells of, 184. Note by Virchow. Why so destructive, 185. Epithelial cancer, 187. A local disease at first, 188. Character of growth, 190. Scirrhus, 191. Structure of, 192. Employs the original tissues, 193. Constitutional vice, 195. Medullary cancer, 196. Structure of, 197. Ulceration of, 199. Constitutional infection, 200. How it takes place, 202. What is it? 204. Treatment, 205. Curable in their earlier stages, 206. General treatment necessary, 207. Local remedies, 209. Complete destruction of the growth necessary, 210.

Chapter IV

Apparatus for secretion, 212. Secreting cells, 213. Note from Virchow. Secretion a vital process, 214.

RECREMENTITIOUS SECRETIONS 114-116

Examples of, 218. Excess of, 219. Defective, 220. Perversion of, 221. Treatment, 222.

EXCREMENTITIOUS SECRETIONS 116-127

Four principal, 223. Excretion by the lungs, 224. Importance of oxygenation, 225. Means for promoting, 226. Carbon excreted, 228. Excretion by the skin, 230. Character of, 230. Observations of Dr. Fourcault on, 231. Increase of, 232. Defect of, 233. Perversion of, 234. Treatment, 235. Excretion by the kidneys, 238. Circumstances influencing, 239. Physical properties, 240. Its solids poisonous, 241. Increased secretion, 243. Defect of, 244. Perversion of, 245. Examination of urine, 246. Treatment, 247. Excretion by the bowels, 251. Office of the liver in, 252. Character of excretion, 253. Increase of, 254. Defect of, 255. Perversion of, 256. Treatment, 257.

Chapter V

Death and life associated together. Constant death of structure. Objection to theories. The body likened to a mansion. Continually , undergoing repairs. Decay of the dead body. Of the living body.

Contents. xi

Tage.

Occupy about the same period of time. A man has no right of property in his body. Living matter no defensive virtue, no excess of vital action. Tissue degeneration. Examples of molecular death. It is this death that causes the symptoms of disease. Arrest of development. Nosology. Application of remedies.

Chapter VI

A complex fluid, 283. Has a distinct, vitality, 264. Susceptibility to change, 265. Classification, 266. Blood-making function, 267. Circumstances that favor it, 268. Good digestion necessary, 270. Removal of waste necessary, 272. As a depot of supply, 273. As a vehicle for the convej^ance of oxygen, 275. As a vehicle for the removal of waste; as a vital stimulant, 278.

OF THE CONSTITUENTS OF THE BLOOD - 153-162

Analysis of the blood, 279. Red Corpuscles — Form of, 281. Relation to other cells. Note from Virchow, 282. Development of blood-corpuscles, 283. Note from Virchow. Origin from the lymphatic glands, 284. Have a determinate life, 285. Carriers of oxygen, 286. Excess, 287. Defect, 288. Relation to the lymphatic system, 289. Perversion, 290. Alterations of, 291.

COLORLESS CORPUSCLES 162-163

Form and relation, 292. Leucocythemia, 293.

The histogenetic material, 294. Its use, 295. Excess, 296. Deficiency, 297. Perversion, 299. Imperfect on account of deficient vitality, 300. Bad blood, 301.

One of the smallest constituents, 302. As an evidence of inflammation, 303.

Combustible material, 305. For the nutrition of the brain, 306. Calorifacient food, 307. Excess, 308. Defect, 309.

xii Contents.

Page.

SALINE MATTERS 168-170

Note from Dr. Stevens. Amount of, in the blood, 310. Soda gives the blood its fluidity, 311. Potash used by the muscular tissues, 312. Demand of the system for, 313. Excess of, 314. Remedies for, 315. Defect of, 319. Symptoms, 320. In chronic disease, 321. Remedies, 322. For septic tendency, 324.

PHOSPHORUS 177

Its combinations, 325. Necessary to nerve tissue, 326. Restoratives, 327.

Removed as soon as formed, 328. Active disintegration, 329. Liebig on, 330. Impairment of the blood from retained secretions, 333. Action of cold, 334. Inflammation from cold, 335. Fever from, 337. Influence on other animal matter, 338. Remedies for, 339.

IMPAIRMENT OF THE BLOOD FROM THE INTRODUCTION OF DE- COMPOSING MATTER FROM WITHOUT - - - 185-194 Note from Chambers. The putrefactive process, 341. Vegetable and animal malaria, 342. Influence upon the system, 343. Producing fever, 345. Duration of fever, 347. Explanation of, 348. Is it good policy to arrest a fever? 349. Treatment of fever, 350.

INFLUENCE OF VEGETABLE MALARIA ON THE BLOOD - 194-199 Cause of periodic diseases, 352. Objections to, 354. The poison cognizable to the senses, 355- Influence on the system, 356. Intermittent fever, 357. This cause of disease may be avoided, 358. Dr. Salisbury's observations, 359. The evidences of a lesion of the blood, 360. Treatment, 363.

INFLUENCE OF ANIMAL MALARIA ON THE BLOOD - - 199-205 Diseases produced, 365. Endemic, epidemic, and infectious, 366. Contagion of cholera, 368. Prophylaxis, 369. Enfeeblement of vital power as a predisposing cause, 370. Treatment, 371.

Chapter VII

Motive power, 377. Lymphatic glands, 378. The lymph, 379. Origin of red and white corpuscles, 380. The basis of the blood, 381. Re-

Contents. xiii

Tago. lation to disease, 382. Syphilis, 383. Scrofula, 385. Quotations

from Drs. Bennett and Paget, 380. Bad blood, 389. Therapeutics,

Chapter VIII

LESIONS OF THE CIRCULATION OF THE BLOOD - - - 214-223 A regular and uniform circulation indispensable to health, 392. The healthy circulation, 393. Capillaries, 395. Classification, 397. General hyperczmia — Active, 400. Causes, 401. Usually excitation of the nervous system, 404. Treatment, 405. Action of special sedatives, 407. Increasing the power of the heart, 408. Removing capillary obstruction, 409. Passive, 411. Capillary congestion, 413. Loss of functional activity, 414. Treatment, 415.

LOCAL HYPEREMIA 223-230

Determination of blood, 419. As observed in the web of a frog's foot, 420. Change of function, 421. Results, 423. Hemorrhage from, 424. Treatment, 425. Congestion, 428. Microscopic appearance, 430. Fluxes, 431. Hemorrhage, 432. Dropsy, 433. Treatment, 435.

Chapter IX

Definition, 440. Note from Virchow. Idiopathic, 442. Causes, 445. Phenomena, 447. As viewed with the microscope, 448. Symptoms, 453. General symptoms, 555. Influence on the blood, 458. Terminations. 460. Exudation, 461. Effusion of blood, 462. Plastic lymph, 463. Mucus, 464. Quotation from Paget, 466. The exudation resembles the blood from which it is drawn, 468. Resolution, 469. Death of a part, 472. Results of Inftavimation, 475. Metastasis, 476. Theory of counter-irritation, 477. Suppuration, 478. Pus, 482. Its composition, 483. Pus globules, 484. Quotation from "Virchow, 485. From Chambers, 486. Formation of pus a vital process, 489. Laudable pus, 490. Scrofulous, 491. Ulceration, 493. Restoration of a part after suppuration, 494. Adhesion, 496. Organization of tymph on free surfaces, 497. Induration, 498. Is inflammation a disease? 500. The process destructive, 503. Not necessary to repair, 504. Treatment, 507.

xiv Contents.

CHAPTER X. Classification, 531

THE BRAIN 270-280

Functions of, 533. Reason, 538. Excess, 539. Defect, 541. Influenced by the general health, 542. Inactive thought, 543. Treatment, 544. Pei version, or Insanity, 546. Delirium, 548. Causes of, 549. Determination of blood, 550. Delirium tremens, 552. Enfeebled circulation, 554. Puerperal mania, 556. Hydrophobia, 560.

THE EMOTIONS --' 281-284

Definition, 562. Classification, 563. They influence the vegetative functions, 564. Excess, 566. Treatment, 567. Defect, 568. Treatment, 569. Perversion, 570. Treatment, 571.

VOLITION 284-289

Definition, 572. Influence on life, 573. Influence in disease, 574. Capable of cultivation, 575. Excess, 576. Treatment, 577. Defect, 578. Treatment, 580. Voluntary motion, 581. Excess, 582. Defect, 583.

SENSATION 289-297

Its location, 584. Man's conscious existence in the brain, 587. Excessive general sensibility, 589. From determination of blood to the brain, 590. From morbid material in the blood, 592. From an enfeebled condition of the brain, 592. Defective general sensibility, 594. From atony, 595. From impaired nutrition, 596. Paralysis, 597. Perverted general sensibility, 599. Excessive local sensibility, 600. Two causes, 602. Defective local sensibility, 603. Perverted local sensibility, 604. Treatment, 605.

Its principal functions, 615. Association with the sympathetic, 616. Co-ordination of movement, 617. Reflex action, 618. Excess, 620. Defect, 621. Perversion, 624. Causes are centric or excentric, 626. Epilepsy, 628. Treatment, 629.

ASSOCIATION OF THE SPINAL WITH THE SYMPATHETIC SYSTEM 304-306 Anatomical connection, 635. In pathological conditions, 636. Examples, 637. Treatment, 639.

Contents — Appendix, the sympathetic system

Its function, 642. Distribution, 643. Draper's theory, 645. Dalton's theory, 646. The real function, 648. Sympathy, 649. Excess, 651. Defect, 654. Perversion, 655.

Page.

306-311

IRRITABILITY

Definition, 657. Conditions necessary, 658. Defect, 660.

312-314

Definition, 663. Mistakes, 664. What it really is, 665. Remedies for defect, 666.

Appendix

Page.

Rational Medicine ............. 318

Natura Sanat, Medicus Curat Morbus 322

Post Hoc, Ergo Propter Hoc 325

Contraria Contrariis vs. Similia Similibus 328

Medicinal Action of Remedies 332

Combination of Remedies 336

The Dose of Medicine 338

Sedatives and Narcotics 339

Remedial Agents — Their True Value 341

On the Use of Bitter Tonics 343

Some Causes of Want of Success in the Use of Tonics 346

Theory vs. Practice 348

On the Best Form for Dispensing Remedies 351

New Treatment 354

Nervous Force 356

Nosology 357

Food for the Sick 360

THE PRINCIPLES OF MEDICINE.

Introduction

Any variation from the standard of healthy function or structure is disease. Human Physiology is the study of the state and activities of the body in health ; Pathology is the study of the state and activities of the body in disease. To study Pathology to advantage, therefore, it is necessary that the student be conversant with the facts and principles of Physiology, and to make a practical application of this knowledge, that he shall have verified those which are cognizable to our senses by personal observation. In this manner he establishes in his own mind a standard of comparison, and is enabled to determine variations from this.

The various phenomena of life in health have certain uniform expressions through the nervous and motor systems, which thus give evidence of the state of the individual, while the physical properties of the various tissues have a uniform standard, representing health. In the same manner, the phenomena of life in disease has certain expressions, which are termed symptoms, which give evidence of the pathological state of the entire body, or of its parts. And the change in the physical properties of parts determines structural lesions.

xviii Introduction.

In studying disease, we estimate separately each change of function with reference to the part producing it, and with reference to the body at large, and each change of structure with reference to its own function and to its influence upon the body at large. In this way we get a correct appreciation of each element of diseased action, as well as its sum, to which we give special names — as fever, inflammation, etc.

Indeed, this is the only method by which disease can be studied to advantage, especially as all rational therapeutic means must be based upon such elemental knowledge. Every known remedy acts upon some special part or function, and its general influence is wholly dependent upon this. I do not speak of medicines, for many of them are given at random, and do not act as remedies, but of those drugs or influences which do resist diseased action and favor healthy nutrition and repair of structure.

We estimate all change of function and structure by the measure of excess, defect, and perversion, which is simple, explicit, and always applicable. Making an analysis of any given case of disease, we »vill find that each of its parts can be measured by this rule, the healthy function and structure being the standard. Each variation must necessarily be an excess, or above this ; a defect, or below this ; or a perversion, a change from this.

Let us, for example, analyze a simple fever by this method. There is an excess in the circulation of the blood, an excess in the amount of heat, and frequently an excess in innervation ; there is a defect in excretion, a defect in digestion and blood-making, and a defect in nutrition ; while there is, to a greater or less extent, a perversion of the blood, in the retention of effete material from deficient secretion, or the presence of an animal or vegetable miasm.

Analyzing a disease in this manner, the treatment becomes

Introduction. xix

very plaiu, simple, and direct, if not specific. For the excess of circulation we use direct or indirect sedatives, which diminish the frequency of the pulse and give a uniform circulation. By the use of baths we diminish the heat. If necessary, there are means which lessen the excitement of the uervous system. The defect of excretion is remedied by diaphoretics, diuretics, and cathartics, which increase the functions of the principal emunctories. And the defect of digestion and nutrition is remedied by the use of bitter tonics, restoratives, and nutritious food, which increase these functions. And lastly, the perversion of the blood is remedied by the use of quinia for the malarial miasm, or the use of sulphites, chlorates, or some mineral acids, when it is an animal miasm or effete matter.

There are two special advantages in studying disease in this way. First — We obtain a correct estimate of the extent and kind of diseased action, and the particular parts affected, and are not so liable to be led astray by the meaningless names of the old Nosology. Second — A rational therapeutics is at once suggested, as the disease is analyzed by the rule of excess, defect, and perversion.

The principal difficulty we meet with in our study of Pathology is the uncertainty of the physiological standard ; not that there is not a well-developed system of Physiology, but that most authors are influenced to some extent by the crude theories of past centuries, to which they endeavor to make facts conform. I prefer Carpenter's Human Physiology, aided by the investigations of Bennett and Chambers, and would suggest the study of these to the reader.

A proper classification of subjects is always of advantage in study, especially when it can be made to lead naturally from first principles to a full development of the subject. I do not know whether such classification is possible in the present state of the science, and feel confident that I have not attained it.

XX

Introduction.

The method I have adopted considers the subjects in the following, order :

Forces operative inf Formative or vital, animal life.

( Electricity.

(Formative.

Secreting.

Necrological.

(Food.

Digestion.

Cell-growth.

j Recrementitious. \ Excrementitious.

Red and white corpuscles.

Albumen.

Fibrin.

-I Fats.

Salts.

Excreta. _ Water.

The influence of morbid material and miasms on the blood.

The lymph and its circulation.

Circulation of the f General. blood. \ Local.

Animal cells.

Nutrition.

Secretion.

The blood.

Inflammation.

Innervation.

' Brain.

(Reason.

Emotions.

Volition.

Sensation. f Automatic movement.

Spinal cord. -< a >i

r (. Sympathy.

Sympathetic Control of vegetative funcganglia. tions.

Contractile fiber. J Irritability.

\ Tonicity.

If we make ourselves masters of the physiology of these functions, so as to know the structure of the animal mechanism, its mode of action, the causes that influence it, and the results attained, we have the theoretical knowledge necessary to the study of Pathology ; and if we are enabled, by previous observations, to determine each of these in the living body, we will be enabled to make a practical use of Pathology, in diagnosis and therapeutics.

Introduction.

xxi

As I will make frequent reference to the classification of Dr. Williams in the progress of the work, I append it here. It will be found in this, that the lesions of excess, defect, and perversion are noted and the results named. In this classification the elements of disease are considered in two classes, primary or ultimate elements, and secondary or proximate elements:

PRIMARY ELEMENTS OF DISEASE.

STRUCTURAL CONSTITUENT.

Contractile fiber.

Nervous structure.

Tubular (the "]

ITS FUNCTION.

S Irritability.

Tonicity.

DISEASE.

STRUCTURAL DISEASE.

Secretion.

conductor of nerve force.) Vesicular (the generator and combiner of nerve

[force.) Secreting structure.

[ Red corpuscles.

White corpuscles.

Fibrin.

Albumen.

Oil, and combus-

tive matters.

Inorganic ingredients

(saline and mineral) Water.

r By respiration.

J By secretion.

Sensation.

Voluntary motion.

Involuntary motion, (excited motor action.)

Sympathetic action.

Elementary components of blood.

Element ary changes -<

/,, 111 By nutrition.

in the blood -„ J „

I by foreign matter.

' Excessive — Hypertrophy.

-{ Deficient — Atrophy.

Perverted — Degeneration

PROXIMATE ELEMENTS OF DISEASE.

Deficient in quantity j Gene Anreinia. \ Parti

General, al.

' General — Plethora.

Excessive in quantity — Hyperteinia.

Perverted in quantity [ — Cachasmia.

Partial — Local hy persemia.

Nutrition of textures.

' Deficient — Atrophy.

Excessive — Hypertrophy.

Degenerations of tissues.

Perverted— -! Morbid deposits.

Morbid growths.

•f £ Increased — Sthenic.

> a Dimin'ed — Asthenic.

f c Increased — Determi- ^ ^| nation of blood. •- "3 Dimin'ed — Congest'n. ^ #S Partly inc. j Inflames Partly dim* \ mat'n.

[Principles of Medicine, pp. 96, 97.

Chapter I. Life

1. In our endeavors to elucidate those principles which should underlie a rational practice of medicine, it is necessary that we examine, so far as we can, that that is called life. It will readily be seen that this should take precedence of function, which is only a manifestation of life.

2. But we are met at the threshold of our inquiry by two classes who ridicule such investigation, and by this means have retarded the development of correct doctrine. The one claim that the chemical and physical forces observed in nature are sufficient to account for all the processes and phenomena of life ; consequently that in a true physiology the whole series of vital operations is to be explained upon chemical principles. Not only so, but that the laws of disease and of therapeutics are to be evolved in the same manner.

3. The second claim that, life being beyond our knowledge, intangible to our senses, and not, therefore, susceptible of reason, it is useless to speculate upon it. With these there are various shades of opinion — some leaning to the chemical theory, others to the supernatural, or the source of all power. Dr. Draper, in bis Human Physiology, attributes life to the soul — " a self-conscious and immortal principle which animates this machine."

He says further, that the physiologist " can not but recall with regret the existing use of many terms, such as mind, intellect, vital principle, spirit, which, though they were at first,

24 Life.

doubtless, employed as expressions of the functions or qualities of the soul, have, in the course of time, gathered other meanings and confused the popular ideas." . . . . " On one of these terms, the vital principle, I may make a few remarks, since, from being a mere expression of convenience, it has by degrees risen among physiologists and physicians to the rank of designating an existing agent, by some regarded as of the same kind as light, heat, electricity, or gravitation — nay, even superior to these, since it is its peculiar attribute to hold them all in check. Animated by this extraordinary power, organic substances are supposed to withstand every external influence, and to submit to physical agents only after this principle has left them. Such a preposterous doctrine will not bear the touch of exact science for a moment. It is only a relic of the old metaphysical system of philosophizing, which accepted a name in lieu of an explanation, which preferred the dogma of the horror of a vacuum to the more simple view of the pressure of the air."

4. It is true, however, that there is organic life, and every one has the evidence of this in his owu person, and as he is brought in contact with it throughout his existence. Whatever it may be, and whatever relations it may bear to other forces in nature, it stands at the threshold of our inquiries, and we can not pass it by without examination. Before giving my own views, I will briefly present those of other writers which have claim to our consideration, and which will pave the wTay for certain definite axioms.

5. Going back to the year 1744, we find Swedenborg, one of the most accurate observers and correct reasoners of the sixteenth century, presenting the matter in this form : " There is a certain formative substance or force that draws the thread from the first living point and afterward continues it to the last point of life. With respect to this formative substance or force, such is the defect of terms that we can predict scarcely anything of it, except that it is the first, the most perfect, the most universal, and the most simple of all the substances and

Stevens on Life. 25

forces of its kingdom ; and that it has assigned to it, within its own little corporeal world, a certain species of omnipresence, power, knowledge, and providence. The first ends, as well as the middle and ultimate ends, according to which causes follow in provisive and given order till they arrive at the ultimate effect, appear to be present to it, and inherent within it, simultaneously and instantly. Consequently, this substance or force represents to itself the state about to be formed, just as if it were a state already formed; and, indeed, the state already formed as a state about to be formed. Moreover, the series of all the contingents, in the order in which the}7 successively appear for the purpose of completing the work of formation, is instantly present to it, and, as it were, involved within it. — Economy of the Animal Kingdom, p. 221.

6. Stevens on Life. — " It is difficult to define life, for we know not what it is; and this is the secret, of all others, that nature will be most likely to keep to herself. We may give it a name, however, and call it what we will ; but the very existence of this mysterious essence, like the cause of heat, is known only by its obvious effects. But these effects are evident to all; we know, for example, that this is the cause which constitutes the difference betwixt the living and the dead body, and the loss of which is the cause of death. We know that, for a time, it endows matter with certain properties — such, for example, as the power of self-preservation. It enables all living animals to resist, within a certain range, the effects of noxious agents, as well as those chemical and other changes that would be injurious to life. It enables them not only to provide for, but to regulate, their own temperature. But, even independent of the property of evolving heat, it enables a living animal, in a certain degree, to resist the effects of extreme cold. It is this which enables the blood, when it forms the new solids in the living body, to organize itself; it is this, also, which endows the whole of the animal creation with the power of communicating vitality to their offspring, and each in return