that work in the fields frees the peasant from the nervous disorders so common in towns. Public opinion on this matter is founded on the ideas of J. J. Rousseau, and other intuitive hygienists, who pretend that, given. exercise, open air, and pure morals, no illness is possible. It is merely necessary to open our eyes to assure ourselves that these preconceived ideas are far from being in accordance with the facts.

In country-women especially we are able to study the phenomena of exhaustion. Like the men they work, perspire, sleep ill and feed badly. Further they have to care for and suckle their usually very numerous children. The life of a young mother of a family in a peasant household is a life of continual exhaustion. Hence women in towns are wrong in believing themselves to have a monopoly of nervous disorders. There are as many neuropathics in the country as in the town, but the neuropathics of the country have not such noisy manifestations. This moderation in the symptoms is due to the simple fact that these patients have not time to complain, and the persons around them have no time to sympathise with them. They do not suffer less, but they hide their suffering more, for fear lest their husbands should add to it by ill-treating them. But neuralgia, gastralgia, vertigo, and neuroses of all kinds are the chief illnesses of peasant-women exhausted by work. As regards hysteria, if its complete manifestations, in the form of seizures, are rarer than in the town, this is due to moral causes which we must point out in passing. For women of the world "to be nervous" is a mark of distinction, "to have crises" is always a means of awakening a lively interest in the persons around. In the country a nervous crisis" is synonymous with an attack of epilepsy.

The salutary fear of epilepsy which exists in the country is a powerful protection against the convulsive movements and the contortions of an hysterical fit, in which moral causes play so great a part.

CHAPTER X.

THE THEORY OF FATIGUE.

Fatigue is a Regulator of Work-Organic Conditions which hasten the onset of the Sensation of Fatigue; Weakness of the Organs; Excess of Reserve Materials-Order and connection of Phenomena of Fatigue-Local and General Fatigue; Immediate and Consecutive Fatigue-The different Processes of Fatigue: (1.) Traumatic Effects of Work on the Motor Organs. (2.) Auto-Intoxication by the Products of Dissimilation. (3.) Organic Exhaustion through Autophagy. (4.) Dynamic Exhaustion through Expenditure of all the Force at the Dis. posal of the Muscular and Nervous Elements. Insufficiency of existing Physiological ideas for explaining all the Phenomena of Fatigue.

We have reviewed the principal physiological phenomena which accompany work, and the changes in the organism which result from muscular activity. We can now briefly sum up and expound the conclusions to be drawn.

Taking a muscular action from its outset, the muscular contraction, and studying it to its termination, which is consecutive fatigue, or stiffness, and to its most serious pathological consequences, overwork and organic exhaustion, we can give a complete picture of the phenomena of fatigue, and we can formulate a rational theory.

Fatigue is the consequence of the material action exercised by work on the organs of movement and on the great organic systems which associate in exercise. The sensation experienced by the individual after ex

cessive muscular activity is a true regulator of work, which becomes the more sensitive the greater the danger which the exercise is causing the organism.

In a much enfeebled man the sensation of fatigue is very painful: this is because in a very feeble body the organs, having less resistance, undergo more easily the damages due to fatigue. In a man of inactive life, whose body is overcharged with reserve materials, very intense fatigue is produced by very little work. This is because violent exercise would, owing to the excessive quantity of reserve materials, very quickly induce stiffness and overwork.

If we examine together the phenomena of work and the phenomena of fatigue, it is easy to see that the one set is derived from the other, and it is easy to grasp the relations of cause and effect by which they are united.

When a muscle contracts forcibly, there occur in all the sensitive parts of the region performing the work shocks and frictions which cause pain. There occurs further in the muscle, by the very fact of work, a process of dissimilation leading to the formation of organic poisonous substances, and the presence of these products of combustion is the cause of the sensation of local powerlessness experienced in a muscle which has been at work.

But the whole organism associates in the work of a single muscle. By the very fact of muscular contraction the blood undergoes an acceleration which necessitates increased activity of the heart. The lungs receive more blood than usual and become congested, the respiratory movements are increased in frequency. Then a new cause of discomfort comes into play, the saturation of the blood by carbonic acid, resulting from the combustion of work. A general suffering in the system results from this transient intoxication, against which the lungs strive by their efforts to expel the noxious gas: breathlessness comes on.

To breathlessness are added the painful sensations due to the heating of the blood, and to the influence which this overheated blood has on the nerve-centres,

and thus is completed the picture of General Fatigue following exercise.

But as soon as the work is over, the functional disturbances of the heart and lungs diminish, through the slowing of the blood current. At the same time the production of carbonic acid diminishes, and the excess which had been formed is rapidly eliminated. The temperature of the blood falls through radiation, and through evaporation of the sweat with which the body is bathed.

All disorder should then cease, but if the exercise has been carried too far, the organism, notwithstanding the muscular repose, finds itself under the influence of a persistent suffering which is Consecutive Fatigue. The limbs which have been at work still suffer from some pain which is not entirely dissipated by repose, for the muscles have been subjected to actual mechanical lesions during the work: shocks, little lacerations of fibrillæ, frictions of surrounding sheaths and synovial membranes, contusions of joints.

But there are other troubles which are not to be explained by any mechanical cause: these are the fever, the general discomfort, the feeling of weakness and prostration, symptoms indicating that the organism is under the influence of a toxic agent. These disorders are due to the passage into the blood of the products of dissimilation with which the muscles are loaded, and which the blood gradually removes from the muscular fibres in order to carry them to the kidneys whose office it is to remove them from the system. The cleansing of the muscular machine by the blood lasts the longer the greater the amount of dross left by the exercise.

During the time which elapses between the formation of these waste products and their expulsion by the urine, the system is in a condition of real poisoning, whence arise the fever of stiffness and the sensation of general discomfort. The nitrogenous waste-products to which febrile stiffness is due, are slowly removed from the muscles and slowly eliminated by the kidneys. During the time preceding their elimination the

organism is under their influence and is struggling against them.

Thus is explained the slow onset of consecutive fatigue, and its persistence after the work is over.

Finally, if the waste-products are too abundant, or the resisting power of the organism insufficient, these noxious substances give rise, by a process of which we are ignorant, to other similar substances, which renew themselves in the blood during many days, and give rise to the severe fevers of overwork.

We are thus led to say that the starting point of all the general phenomena of fatigue is a poisoning of the organism by its own products of dissimilation. All the phases of general fatigue, from the simple discomfort which causes momentary muscular powerlessness, to extreme breathlessness to which animals succumb, and to the fever of overwork which simulates typhus, are due to these more or less active poisonous substances, retained a longer or a shorter time in the blood.

But all the disturbances of nutrition which follow work are not to be explained by an auto-intoxication of the body. In certain forms of overwork we see the processes of nutrition carried on by feeding on the tissues most essential to life. The reserve materials being exhausted, the tissues forming the woof of the organs are in turn attacked, and the body, instead of assimilating its own noxious materials, as in the other forms of overwork, robs itself on the contrary of the organic elements indispensable to the equilibrium of health. There is no longer, in this case, auto-intoxication, but autophagy and exhaustion

II.

Among the phenomena of fatigue there is a whole series of which the methodical classification seems at present impossible, because too little is known about them. They cannot be classed with the mechanical phenomena, such as the little lesions from which the muscle suffers, nor with the nutritive disturbances such