The exercises in realization lead us on to the use of the rhythmic breath and should be reasonably well mastered before going on to it. Rhythmical breathing will be found to improve the powers of relaxation already gained. It also stills and concentrates the mind as a basis for later visualization work apart from making available an increase of psychic energy and etheric vitality — to say nothing of the beneficial physical effects, as most of us use our lungs inefficiently most of the time.
The important thing to watch for here is not to strain, nor to hold the breath, in or out, by an inhibitory effect of will. There must be no forced effect. The air should be taken in to the bottom of the lungs first by the simple method of pushing the abdomen out (i.e. the diaphragm down) and thus causing the air to be sucked naturally into the lungs until they are filled to the top.
Again, there should be no forced retention of the breath with consequent strain on the lung tissue, but the air should be retained for the requisite time by holding the diaphragm down and the chest wall out. If the chest is tapped sharply it should cause part of the air to be expelled, thus proving that there is no barrier in the throat or mouth.
To breathe out, suck the abdomen in (i.e. the diaphragm up) so that the air is expelled naturally and is felt to leave the top of the lungs last of all. Keep the breath held out by use of the diaphragm and trunk muscles.
For general purpose we use the technique known as the fourfold breath. Inhale slowly to a count of eight; retain the breath to a count of four; exhale at the same speed to a count or eight; hold the lungs empty to a count of four.
Alternatively, one can count four and two, or six and three, or whatever seems most comfortable according to ones individual constitution, speed of counting and breathing, and lung capacity. The important thing is avoidance of strain or “over breathing”, giving symptoms of dizziness.