The under arm alternates with the upper, recovering as it comes down, pull ing as it recovers. This fortunately is in stinctive, and does not have to be learned. For the under arm also there are two forms of the stroke. The arm may come down in front of the body and parallel with the surface of the water, exactly like the upper arm ; or it may be carried out at the side and at right angles with the surface. The former method is reputed to be slightly faster; the latter is some what the better gymnastics, and is proba bly at least as good for swimming dis tance. The recovery is exactly like that of the upper arm.
The separate details of the side-stroke are, then, simple enough, and consid erably easier than the corresponding movements of the breast-stroke. The only difficulty is in getting them to work together. Here, therefore, comes in the special advantage of practice in the air.
To time the side-stroke, lie in the slide position. Carry the upper arm forward ; sweep it back in its usual stroke. As it comes down, and just before it reaches the level of the face, take in the breath through the mouth. Rest until it is time for another breath, exhale quietly through the nose and repeat.
This matter of breathing is most im portant. One cannot swim, or do anything else, unless one breathes comfortably. There should, therefore, be no haphazard breathing. Every stroke should have its time for breath arranged for, like any other motion. Persons who try for years to learn to swim, and make no progress, usually suffer from a nervous spasm or an old habit which makes them hold the breath during their struggles.
The reason for inhaling through the mouth instead of the nose is obvious. One can never be quite sure, especially in rough water, which fluid he is going to suck in with his next breath. A mouth ful of water can be spewed out again, or even swallowed on a pinch; for most of us are quite accustomed to having water in our mouths. But a noseful of water is another matter. The victim gasps and chokes. Not always does he escape with his life; for many cases of drowning at tributed to cramp are probably in reality cases of strangling by water taken in through the nose. By all means, there fore, the beginner should start right. ' The breath, then, is taken in as the up per arm comes down. At the same time the legs open slowly for their stroke. They snap togetherwhen the upper hand reaches the thigh. The arms rest during the closing of the legs, and remain motion less, the upper arm at the side, the lower stretched out at full reach, until the mo mentum of the kick begins to die away.
Then the under arm comes down and the upper arm recovers. In these prelimi nary exercises, however, the movements of the under arm must be omitted.
For this and other reasons, the time of the stroke is most conveniently taken from th e upper arm. As this makes its pull, the breath comes in and the legs open. As it finishes at the thigh, the legs fall in. There is a moment's rest while the body slides, after which the upper arm goes for ward again. The timing of the under arm and time for exhaling the breath will take care of themselves involuntarily.
Thus far nothing has been said con cerning the side on which one shall swim. For this one must consult his own feel ing as to which of the two seems the more natural. In case of doubt, one is usually advised to keep the left side up, for the sake of the slightly lessened pressure on the heart; though it is pretty difficult to see how this can really make the slightest difference. The best side is, however, both sides. If one starts from the begin ning practicing equally on each side, it is about as easy to learn on both sides as on one. There is a considerable advan tage in this. The side-stroke is unsym metrical, and is therefore vastly better gymnastics when swum equally on each side. Moreover, it is always pleasant, and often convenient, to be able to face either way. The change, too, is restful. This is an additional reason for making the two arm-movements unlike, and bringing down the lower at right angles with the surface.
Here is the place where the beginner makes most haste by going slowly. He will do well to practice these preliminary exercises for some weeks in the spring be fore he goes into the water, and to repeat them from time to time during the early stages of his progress, to make sure that he is not getting into bad habits. A child may with profit practice them in a bath tub.
When one finally gets into the water, a convenient procedure is this : Select a beach or other flat surface which slopes somewhat steeply ; lie with the head toward shore, half in the water, half out, and practice the scissor-kick alone, until it is thoroughly learned. Gradually work offshore a foot or two, supporting one's self on the hands, and drive the body ashore again with one vigorous stroke of the legs. After this, try several kicks in succession, in water waist-deep, using only the lower hand for support.