To arrive at full possession of the powers of the dream-state, it is necessary first to exclude the attack ofthe sights, sounds, etc. of the outer world upon the physical organs. It is quite possible indeed to be aware in the dream-trance of the outer physical world through the subtle senses which belong to the subtle body; one may be aware of them just so far as one chooses and on a much wider scale than in the waking condition: for the subtle senses have a far more powerful range than the gross physical organs, a range which may be made practically unlimited. But this awareness of the physical world through the subtle senses is something quite different from our normal awareness of it through the physical organs; the latter is incompatible with the settled state of trance, for the pressure of the physical senses breaks the Samadhi and calls back the mind to live in their normal field where alone they have power. But the subtle senses have power both upon their own planes and upon the physical world, though this is to them more remote than their own world of being. In Yoga various devices are used to seal up the doors of the physical sense, some of them physical devices; but the one all-sufficient means is a force of concentration by which the mind is drawn inward to depths where the call of physical things can no longer easily attain to it. A second necessity is to get rid of the intervention of physical sleep. The ordinary habit of the mind when it goes in away from contact with physical things is to fall into the torpor of sleep or its dreams, and therefore when called in for the purposes of Samadhi, it gives or tends to give, at the first chance, by sheer force of habit, not the response demanded, but its usual response of physical slumber. This habit of the mind has to be got rid of; the mind has to learn to be awake in the dream state, in possession of itself, not with the outgoing, but with an ingathered wakefulness in which, though immersed in itself, it exercises all its powers.

Still like a statue on its pedestal,
Lone in the silence and to vastness bared,
Against midnight's dumb abysses piled in front
A columned shaft of fire and light she rose.