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supplement the immaterial reward of early dinner when he burst in upon conscious virtue with something more them. substantial.” The solicitor took a "I am back sooner than I intended," cheque-book from a drawer. “He he shouted, “and we all start for Deal thinks that £500 "
this afternoon. Ethel, we will stay at "It is wonderful,” muttered Bellamy; an hotel the whole time, and you shall “the very sum-"
have a real holiday from housekeepThe cheque was written and acknowl. ing." edged, and when he went into the “But can we afford it, James?" street Bellamy's hands were shaking. “Afford it!” he yelled. "Afford it! “My nerves are upset,” he whispered. Look at that!” And he cast the cheque "I want a change.”.
upon the table. Mr. Bellamy's family were at their
Bennet Copplestone. The Dornbid Magazine.
Fatigue is a phase of life to which search that has recently affected all few are strangers. That which the civilized peoples, and has extended word denotes is an experience only too even to the state that is now so promifamiliar to most persons, but in varied nent in the eyes of the world-Japan. character and degree. It is a feature Italy has grand traditions to inspire of perfect health, and yet is a link her; and the degree in which she exwith disease, since it is produced with celled in the study of life three cen. undue readiness in morbid states, and turies ago may have inspired the note in some it constitutes a conspicuous worthy work in physiology which her symptom. Not only is it varied in its sons have lately achieved. manifestation, but it has many-sided Contagion is not confined to disease; relations; and some of these involve it is manifested also in tendencies of considerable scientific interest. As a thought and work. The special study result of activity in the normal state, that has been given by Italians to the it is a part of physiology, the study subject of fatigue seems chiefly due of the living body in health; and as to the fact that one of their best known such it has been recently made the physiologists, Professor Mosso, has subject of much research, which has made it for many years a favorite subresulted in discoveries of considerable ject of investigation. He has published importance. It is a difficult subject the results of his work in many papers, for investigation, for reasons which and has condensed them in a small volwill presently be mentioned; and it is ume designed for popular consumption, curious that the study it has received which has been translated into Enghas been chiefly at the hands of Ital- lish. But fatigue is largely a feeling, ians. That nation has shared conspic- a fact of sensation; and our meagre uously the impulse to scientific re- knowledge of the processes which underlie its sensory phenomena was ad sensation for the most part eludes our mirably described by Sir Michael Foster grasp. The actual sensory functions in his Rede Lecture on “Weariness," of the nerves can be tested—the sengiven before the University of Cam. sitiveness of the skin to touch or pain, bridge. This lecture is a remarkable of the auditory nerve to hearing, of the example of the use of simple, apt lan- eye to light and color; but the multiguage to describe recondite scientific tudinous sensations of which the brain facts.
*1"Fatigue." By A. Mosso,' Professor of By Professor Sir Michael Foster, K.C.B., Physiology in the University of Turin. Trans. “Nineteenth century," September 1893. lated by Margaret Drummond, M.A., and W. 3 “Remarks on Replies by Teachers to QuesB. Drummond M.B., London: Swan Sonnens
tions respecting Mental Fatigue." By Francis chein, 1804.
Galton, F.R.8., “Journal of the Anthropo2“Weariness." The Rede Lecture, de- logical Institute," vol. XVIII, 1889. livered in the University of Cambridge, 1898.
may be conscious elude the methods of It is curious that a fact of life so scientific research even in its latest keenly and generally felt as is fatigue elaboration. They cannot be described should have received systematic study in words, for our feelings altogether only in recent years. The cause of its transcend the capacities of language; neglect becomes perceptible when we and only similes can be used, which discern how little even the latest re- mislead rather than inform. To this search can teach us of the nature of class of uncomprehended sensations be. weariness, how little science can add long those which are caused by overto that which every one knows by ex- exertion. The "feelings" of fatigue perience. We may find an inkling of constitute an obstacle to exertion often this in the words we use to designate insuperable, but their purely subjective the condition. The word, “fatigue" and nature makes their scientific investi. all its synonyms, "tiredness," "weari- gation almost impossible. That which Dess," "exhaustion," and the like, are is only felt cannot be recorded, and positive terms. They are designations eludes the precise observation that is of the definite sensation which attends necessary for accurate study. over-exertion. Yet, when we think of Hence the only aspect of fatigue fatigue and exhaustion, we think of which is open to research is its negathe inability for further exertion which tive nature, the diminished power accompanies the sensation quite as which results from over-exertion. The much as of the sensation itself. There fact that strength is lessened by conare thus two sides to our perception of tinued effort, even in moderate degree, fatigue-a positive side, the sensation is a matter of familiar observation, of weariness, and a negative side, the Animal life sometimes affords us strikdiminished power of exertion. Each ing examples; and one pertinent in. is prominent in our thoughts. When stance is the utter exhaustion of migrawe speak of being "tired," we mean, tory birds when they have had to fly generally, that we cannot go on with against an adverse wind. Birds vary the effort; yet only the definite sensa- much in their power of long flight; and tion finds expression in our words. the distance travelled by swallows and "Exhaustion” is the nearest approach swifts is less marvellous than that to a distinctly negative term we use, covered by birds such as quails, which but this is really positive. The fact seem to have no great strength of is, indeed, an illustration of the way wing, and yet are migratory. On in which all sensations dominate our reaching land they are often scarcely thoughts and the words which convey able to move; and many fail, simply them. Our feelings are the most defi- from exhaustion, to reach the shore. nite realities to our consciousness; they Carrier pigeons, which have flown long govern our language and often exert distances, present the same symptoms a strong influence on more than our of exhaustion; and the effect of overwords.
work has been found by Mosso to be Unfortunately for science, feeling or shown in them by increased temperas ture, and even by an altered color of beneath the writing points in a second, the muscles which move the wings. a difference in space of one tenth of
But such observations are not definite an inch will correspond to one 240th enough for modern science. The in- of a second, a period far too short to fluence of muscular exertion can be ob be discerned by the eye. Moreover, to served, measured, and recorded with aid the comparison of space and time, precision. The aid which mechanics the science of acoustics is called into have given to the study of life is re- service. Every tuning-fork vibrates a markable. It is not a jest, but a sober definite number of times in a second. fact, to say that the science of physiol. It may be made to record its vibrations ogy has been revolutionized by a re- on the cylinder while the observations volving cylinder. Moved by clockwork are made; and thus an absolute measat varying speeds, this simple apparatus ure of time is written simultaneously has opened up a range of precise ob- on the blackened surface, which indiservation which has almost trans- cates, with perfect certainty, the interformed the investigation of vital val of time to which a given space phenomena. To those who know any- corresponds. By this means facts have thing of physiological science, the use been ascertained regarding every proof such an apparatus is so familiar that cess of the animal body which can pro they have perhaps never thought of duce a movement. Even the rate of what physiology would be without it. the transmission of a nerve-impulse has But, if the knowledge gained by its been measured. Although a touch, and means could be eliminated, that which the feeling it produces, seem simulremains would be little more than was taneous to the most careful observer, perceived fifty years ago, except in the they are found to be separated by a domain of the chemistry of life. It is, large fraction of a second. indeed, strange how deep a debt By an ingenious contrivance, which physiology owes to simple mechanics. he calls the "ergograph,” Mosso has
For those who are not familiar with recorded the strength exerted by the practical physiology it may be said that muscles which bend one of the fingers. the cylinder is covered with paper If a weight is attached to the instrublackened by the soot of such a smoke ment, the exhaustion of the muscles as is given off by burning camphor on successive contractions can be asOn this black surface, as the cylinder certained and indicated by the height revolves, a white line is traced by a to which the weight is raised; and point attached to a lever; this lever this is recorded by the tracing of the magnifies, perhaps a dozen times, the lever. movement to be recorded. The cylin- The gradual diminution of the strength der, about two feet in circumference, which can be exerted, slow or quick, may be made to revolve once a minute according to the various conditions of or oftener, even once in a few seconds; the body, is presented in a large series and any process which can cause a of diagrams in Mosso's book. The movement can thus be made to record diminution occurs equally, whether the itself in the variation of a definite line. muscles are set in action by the will Two processes can be made to produce or are stimulated by an electrical a record at the same time; and thus the shock to the nerves. The features of interval which separates them is re- their exhaustion have been studied vealed, although it may be far smaller more completely by experiments on ani. than could be distinguished by the eye. mals, in which, indeed, Mosso was long If twenty-four inches of paper pass anticipated. The frog is a convenient agent for such observations, because it hinders the response and can be rewill go on living for a long time after moved by simple irrigation. being killed. The statement may seem This fact makes us consider more somewhat Hibernian; but the division closely what occurs in the muscle when of the spinal cord from the brain does it contracts. The manner in which not end life at once, as it would in a these wonderful fibres of the muscular higher animal. The heart continues substance shorten and widen under a to beat and the muscles to contract, al stimulus, is a marvel of which we though the brain cannot act on the understand but little. An impulse body, and no sensation can reach the comes to them through the nerves—an brain. This fact is extremely con- impulse which may be produced by the venient for physiologists. They can will or generated by an electrical study many of the facts of life, and stimulation of the nerve; and the fibres Fet know that they are causing no with one accord become broader and pain, and that the will of the subject shorter, drawing together the ends of does not influence the facts they ob- the muscle and thus moving whatever serve.
is mobile to which the muscle is at.
tached. By this simultaneous action, One of these facts is perhaps the united in the vast number of fibres that most important that has been ascer- compose a muscle, these microscopic tained regarding the exhaustion which bands exert a force that is marvellous. accompanies what we call fatigue. If The single fibres are far too small to the muscles of the leg of a frog, thus be visible to the naked eye, yet they deprived of conscious feeling, are are so disposed as to pass into synstimulated by electricity so as to cause chronous contraction, and furnish a contractions in quick succession, these striking example of the way in which steadily diminish in strength. The number replaces size. Indeed, multiheight to which the attached lever plicity is size. Yet it needs an effort rises diminishes rapidly, as is shown to comprehend that a collection of by the tracing which it records on the fibres, each comparable in dimension cylinder, The diminution goes on until to a gossamer thread, just visible as it the contraction no longer occurs. The floats in the sunbeams, should be capasame electrical current passed through ble of raising half a hundred-weight or. the nerve, which at first produced more. energetic movement, no longer causes Whence comes the energy thus contraction in the muscle. If, then, exerted? The question may be unthe artery of the limb is divided and necessary; the answer may be well distilled water is injected until it flows known. Yet upon it depends in part out freely from the veins, muscular our explanation of fatigue. That force contractions can again be obtained, which moves a weight cannot arise and they continue for a short time. de novo is now a matter of common The significance of this fact is clear. knowledge. It can only be produced Distilled water cannot renew the con- by being transformed, by undergoing tractile elements of the muscle. All a change in its relation to matter. that it can do is, so to speak, to wash Radium, indeed, gives a startling out the muscle. Hence it is certain shock to our conceptions, but we are that the cessation of the contractions, beginning to perceive that it does not under rapid stimulation, is due not really disarrange our old ideas, whatonly to exhaustion of the muscle, but ever it may add to them. We can still to the presence of something which trust our old conclusions as to the
source of muscular energy. Atoms call “combustion," and yet analogous. form closer combinations. In the But the process takes place in the livmuscle, before it contracts, they are ing tissue; and life shrouds with its held apart by interatomic motion, min veil of mystery all that occurs within nute in degree but vast in total amount, its domain. in the elaborate compounds of which T he hindering effect of the products muscle consists, and also in the oxygen of muscular action is peculiarly in. which comes in the blood to the mus- structive. We can understand that cles. When what we call a "stimulus" their removal, even by the agency of acts on tbe fibres, the atoms composing distilled water, may enable the muscle them suddenly form closer compounds again to respond to a stimulus which by means of the adjacent oxygen. This reaches it; and we can understand that, has a potent attraction for them, to if not removed, these products hinder, which they could not yield until the in all animals, the ability to maintain "stimulus," as it were shaking them, continuous effort. At the same time set them free. Their closer union it must be remembered that another liberates the force which kept them and perhaps the most potent factor in separate. The mystery of muscle is the decay of strength caused by overthat the released energy is so seized exertion is the exhaustion of the eleand united as to make the whole mus- ments of the muscles from which the cle shorten with a force proportioned energy is derived. Their renewal to its size. We do not know how this under the influence of life is speedy, combination of the energy released is ef- but it needs time. The quick repetifected; but we can see its analogy when tion of muscular exertion does not percoal-gås, mixed with air, is exploded mit the living tissues to appropriate, in the cylinder of a gas engine. The in adequate degree, the elements preatoms of coal-gas and of the oxygen sented to them; and thus exhaustion is of the air are kept apart by interatomic induced, which is the essential cause motion, “latent energy"; the spark is of the failure from fatigue, although here the stimulus which disturbs the its influence is accompanied, and to balance; closer combination releases the some extent anticipated, by the hinderenergy, and the piston is moved, while ing effect of the products of action. carbonic acid and water result from These facts enable us to understand the union of the atoms previously kept better the sensation of fatigue, al. apart.
though their application has hardly yet Between this process and that in the been fully recognized by the students muscle there is a wide and unbridged of the subject. They are of interest, gulf. Yet there is an analogy suffi. also, as an example of the relation ciently close to be instructive. The which one branch of science bears to carbonic acid formed in the gas engine another. Facts which seem isolated would extinguish any light placed in are found to be connected; one disit; through it no other spark could covery may lead to another quite difpass. The combination of atoms in the ferent in character. We all know that muscle which releases energy produces a prominent effect of over-exertion is substances that interfere with a repe- true muscular weariness, a sensation tition of the process. They are toxic experienced in the muscles themselves. to the muscle in so far as they hinder As a feeling, this eludes investigation, the process which causes contraction, as do all our pure sensations; but the They result from chemical union, less discoveries of histology, the branch of direct and less close than what we science which is concerned with the