This third stage is as follows. To the respiratory distress succeeds a sensation of anguish generalised throughout the organism. The head feels as if bound by an iron band. Vertigo is very distressing. All sensations become more vague; the brain is overcome by a kind of drunkenness. The subject begins to become unconscious of what is passing, his muscles continue to work mechanically for a time, then they stop, and the man falls in a faint.

At this time respiration is of a different type to that of the last stage; the two periods are both short, jerky, occasionally interrupted; with them are mingled swallowing movements and hiccough. The heart-beat is feeble and intermittent. The pulse is small, irregular, and imperceptible. When exercise is continued to these extreme limits it is almost always stopped by grave syncope, and unless prompt help be given the syncope may be fatal.

II.

The description of breathlessness which we have given is no picture of the imagination. We have studied some of the phenomena on our own person and on that of a friend who has willingly helped us in our researches.*

As to the more serious phenomena, they are often observed in England, the country of sport. It is by no means rare to see a severe fainting fit interrupt a runner in his course. Often a match between two pedestrians ends before either has reached the goal. One of the champions, breathless to the last degree, falls unconscious, and is only restored to life by the cordials and rubbings of his attendants. Often the unfortunate breathless man comes to himself, and after eliminating some puffs of the carbonic acid which is stifling him, wishes to continue the contest, but his muscles are impregnated with this gas, a poison which deprives them of all energy. The heart itself, bathed in blood overcharged with this poisonous product, loses power the heart-muscle is paralysed and the circulation

This friend was M. A. du Mazaubrun of Limoges; we take this opportunity of thanking him for his intelligent assistance.

stopped. The case is then unusually grave, and the most energetic measures have sometimes to be employed to restore to life the man who has overstepped the limits of prudence.

One of our friends who was somewhat enfeebled by excessive intellectual labours wished to resume bodily exercises which he had long discontinued, and returned to the fencing-school. He was an excellent fencer, and when he had the foil in his hand he forgot his exhaustion and only thought of regaining his quickness of attack, and his energy of thrust. After ten minutes he became very breathless, but he would not stop. All at once he fell down insensible, his face pale, his forehead covered with a cold sweat; his breathing and pulse had stopped. We at once went to his assistance, and thanks to the horizontal position in which we kept him, and to vigorous flicking of the chest and temples with a wet towel, his heart began to beat again and consciousness returned.

It was a syncope produced by breathlessness, the occurrence of which was favoured by the feebleness of the patient.

Syncope is a frequent termination of breathlessness, just as of asphyxia, of which breathlessness is in reality only a peculiar form.

Such are the symptoms and course of respiratory fatigue, and such are the dangers to which a person fighting against breathlessness is exposed.

Breathlessness is a ne plus ultra imposed upon us by the instinct of self-preservation. The severe suffering which accompanies it is a true cry of distress on the part of the organism to which the consciousness cannot shut its ears with impunity.

Animals which are overdriven usually succumb to breathlessness. The horse, which as Buffon said, "dies for better obedience," gives us the most frequent opportunity of studying the mode of death of which we are speaking. It is common enough to see a horse fall dead beneath its rider. When respiration is failing, and it wishes to pause to recover breath, it is answered with

whip and spur, and continues to gallop. But the moment comes when the dose of carbonic acid which has accumulated in the organism, owing to the insensate speed demanded of it, becomes fatal, and the animal drops down dead from asphyxia.

Most of the animals which die suddenly during too violent work succumb to breathlessness. It is a common accident with all animals from which great swiftness is demanded, and the very birds, so well made for speed, may become its victims.

We saw a curious instance of death from breathlessness in a carrier-pigeon.

Carrier-pigeons undergo a special training, which consists in setting them free at points continually more and more remote from their home. The bird is driven by its instinct to return to its usual home, and whether it be from haste to reach the pigeon-house, or whether it be from a spirit of emulation, it seems to fly home as swiftly as it possibly can.

A friend of ours had a pigeon, which was the swiftest in the district, and which had never been beaten in a race. One day its master, who lived at Limoges, had sent it to Bayonne, where it was to be set free, and we were awaiting its return, well knowing that it would soon traverse the 375 miles. This time its speed exceeded our expectation, and seven hours after the time at which it was set free the valiant little bird appeared; we gave a cry of admiration, but the poor pigeon paid for its glorious prowess with its life. Just when it was about to settle on the pigeon-house we saw it flap its wings, turn, and fall helpless on the roof, where it was dashed to pieces. The poor pigeon had exceeded the measure of its strength it died of breathlessness from having flown too quickly.*

* We sometimes see fatigued quails fall on ships. We have even seen them fall on houses or in the streets. In these cases the bird is suffering from muscular fatigue, which is a much less serious condition than breathlessness. Quails which are thus caught, owing to their inability to fly, do not die, and may be kept alive for years.

We must remark that not every animal which dies from fatigue dies of breathlessness. Hunted animals usually die in quite another manner, which we shall study under the name of overwork. However, in hunting it sometimes happens that an animal is forced to run without stopping until it dies. This is the case with an animal which breaks cover, and trusts to its speed to elude the hounds. If the beast is too young, it may be taken before it has gained the wood in which it hoped to find new shelter. Then it is breathlessness which gives it up to the hunter. But it is rare for this to happen, and more commonly the hunted animal stops from time to time, to double if it be a deer or a hare, or to stand at bay if it be a wild boar.

Even these very short rests are enough for the animal to render its respiration regular, and to eliminate the excess of carbonic acid with which it is being poisoned. After a minute or two it is ready to start afresh, and the chase may in this manner last a whole day. In this case, if the animal is in the end hunted to death, death is not due simply to insufficiency of respiration; it results from a profound decomposition of the tissues, which we shall study in the chapter on Overwork

CHAPTER V.

STIFFNESS.

Return to the Gymnasium; A Sleepless Night-Febrile Stiffness -Three Degrees of Stiffness of Fatigue-Causes of Stiffness; Immunity due to Habituation-Explanation of SymptomsImperfection of Theories Local Symptoms; They are due to Trauma - General Symptoms; They are due to AutoIntoxication Influence of Muscular Deposit of Urates Exercise on their Formation; Diversity of opinion of Authors -Personal Observations-Conditions which cause Variations in the Formation of Deposits after Work-Slow appearance of the Deposits after Exercise-Influence of the Intensity of the Work on their Formation — Hitherto misunderstood influence of Training-Constant Correlation observed between the Production of Stiffness and the Formation of Deposits-This Correlation is found in all circumstances which render the Individual more liable to Fatigue-Influence of Moral Causes on Consecutive Fatigue and on the Deposits.

If a person has for some months taken no active exercise, and then returns to the gymnasium, he usually finds at the outset that he retains all his old vigour. He performs all the most difficult movements with as much ease as when they were assiduously practised. He gives himself up to the pleasure of long-discontinued performances, he is prodigal with the work of his muscles, and finally, after a long practice, he goes away astonished at feeling no fatigue after an hour so well spent.

In the evening, however, a little weariness and sleepiness make him think that the violent exercise he has taken makes him need more sleep than usual, and he hastens to seek in sleep the reparation of the force he has expended.

But sleep does not come.

It is made impossible by