column is soon associated in various evolutions which no longer allow it to play a merely passive part.

On the trapeze, the rings, the horizontal bar, the period of suspension of the body by the arms is merely a sort of short preface to the exercise. Climbing a ladder or a rope by the hands alone, allow, on the contrary, a man to leave throughout the whole exercise his trunk inert and supple, while the arms alone are at work.

On the parallel bars the body is supported by the arms, and remains inert during the movements of horizontal progression brought about by the regular movements of the hands. A great number of the movements performed on the parallel bars allow the spinal column to benefit by the action of the weight which tends to lessen its curves.

From an orthopaedic standpoint, the mechanism of the exercises of which we have just been speaking, has been made use of in the correction of deviations of figure. Most of the cures of the "Swedish" gymnastics are based upon the method of suspending the patient by the hands or supporting him by the arms, the body being abandoned to the weight which tends to straighten the crooked spine.

The compass of this volume will not allow us to study in detail the different exercises, and to analyse and explain their mechanism, that is the manner in which they bring into play the different bony levers of which the animal machine is made up. We have merely been able broadly to delineate the mode of action of each part of the body in muscular work, and to indicate the part played by the limbs, the pelvis, the vertebral column, and the ribs in the more common movements.

This rapid sketch has for its special object to make the changes comprehensible which each exercise can produce in the different regions of the body, whether by chiefly developing certain muscular groups which act more than the others, or by modifying the direction of certain bones or bony systems, which support directly or indirectly pressures and shocks, or are placed in vicious attitudes.

PART V.

THE RESULTS OF EXERCISE.

DEVELOP

GENERAL EFFECTS OF EXERCISE-EXERCISES WHICH THE CHEST-LOCAL EFFECTS OF EXERCISE EXERCISES WHICH PRODUCE DEFORMITY-EXERCISES WHICH DO NOT PRODUCE

DEFORMITY.

CHAPTER I.

GENERAL EFFECTS OF EXERCISE.

Varying Nature of the Effects of Exercise-Its two Chief Results, the Losses and the Gains-Increased Activity of Combustions, Resulting in the Using-up of the Reserve Materials-Why is Nutrition more Active? Part Played by Oxygen-The "Need for Exercise"; to What it is Due-Accumulation of Reserve Materials-Sluggish Nutrition-Why an Inactive Man Fears Fatigue" - Insufficient Exercise - Unwholesome Effects on Nutrition-Slackening of the Process of Dissimilation-Obesity -Deficient Oxygen and Excess of Reserve Materials-Incomplete Oxidations-Gout-Necessity for Exercise-Effects Common to all Forms of Muscular Work-Special Effects according to the Quality of the Work-Observation on Horses -Trotting and Walking.

I.

If we go into a gymnasium and examine a group of men who are doing exercise by the doctor's orders, we can hardly believe that the same medicament can be suitable for such different temperaments, for such widely opposed disturbances of health. We ask how the same method of treatment can be advantageously applied to men of a stout build, with red faces and exuberant flesh, and to men who are thin, pale, and emaciated.

It will surprise us, however, after a few weeks, when we come to study afresh these different types, to find how much less contrast they now exhibit in structure and physiognomy. The heavy man has lost weight, while the man who was too light has gained it; the former has no longer the violet tint which announced vascular plethora; the latter, on the contrary, has a brighter colouring: the blood flows to his formerly discoloured cheeks, and his whole appearance announces a more intense life.

The practice of exercise tends to impress an identical seal on the most various temperaments, and to reduce to the same type the most opposite constitutions.

This is because exercise produces in the system two absolutely different effects; it increases the process of assimilation, thanks to which the body gains new tissues, and it accelerates the process of dissimilation, which leads to the destruction of certain materials.

The process of dissimilation is more active, owing to the greater intensity of the vital combustions. A muscle which works is a muscle which becomes heated, and this cannot occur without the burning of a certain quantity of tissue. The excessive production of heat which accompanies work, the rapid combustion of certain materials of the body, and their elimination from the system as waste-products of combustion, these are the causes of loss of weight in exercise.

It is not so easy to explain increase in body-weight, under the influence of methodical work.

"Under the influence of gymnastic exercise," says Dujardin-Baumetz, "the activity of the cellular functions increases and becomes more regular, the intracellular combustions become more active; the leucomaïnes, these toxic materials which the organic cell is constantly manufacturing, are more actively eliminated, and the general effect is that the fats are burned up, the cellular functions regulated, there is established an equilibrium between the cells of the spinal cord and those of the brain, in a word, general nutrition becomes more active."

With due deference to the eminent professor, we cannot help thinking that the explanation he gives of the effects of exercise is insufficient. It simply states a fact : nutrition becomes more active. We can well understand how increased activity of nutrition implies the idea of more active absorption of materials derived from the food, and the more regular deposit of these materials in the living organs and tissues. But why does nutrition

• Bulletin de thérapeutique, May 15, 1887.