Let us turn to Science, and see how far similar doors are opening there for the science of our day. You may remember that I pointed out to you that science was now rather at its wits’ end as regards observation. It seems to have reached the limit of the delicacy of its outer apparatus. How shall it continue to observe? By means of those same senses that I have been speaking of in relation to the verification of religious teachings, but in science you can begin a little lower down. In the physical world of matter, our own world, science is now recognising not only solid, liquid, gas, but also ether, and beyond ether, possible finenesses arising, so that there may be many ethers, as indeed was suggested in that famous classification of vibrations which Sir William Crookes gave in one of his addresses a few years ago. Let it stand for the moment as a matter of observation of higher sight that there are more ethers than one that science will gradually conquer. But science is not yet able to see even the chemical atom, and that is only on the plane of the gas, the third fineness of matter. The atom escapes by its subtlety, by its minuteness, and yet it would not be a very difficult thing for most of you to develop in yourselves the power of seeing as far as that, for it is only physical matter. It is not now the seeing of another kind of matter altogether, like that of the astral world; it is only the making a little keener of your present physical sight. Now I wonder how many of you, if you were on board ship, quiet, with the air very pure, if you looked into the atmosphere around you, would see dancing in that atmosphere a number of tiny brilliant sparks. Probably a large number of you. Try it next time you happen to be out on the sea. Sit with your back to the sun, otherwise your eyes will become dazzled; fix your gaze at the distance at which you can see an object clearly, so as not to strain the eyes; focus your eyes, say at a distance of four or five yards away, not near enough to cause any strain by the crossing of the eyes; you must not cross the axes of the eyes, that is, you must not squint; that, prolonged, will injure the eyes. Let them look quite easily out a few yards away from you into the empty air, and stay quite quietly looking at that point. Probably most of you presently would begin to see a number of brilliant little sparks dancing like motes in a sunbeam. One word of warning I must give you: if, in fixing your attention on one of those, it slowly glides away out of sight, round the corner as it were, then it is only something in the retina, and the humour of the eyes carries that gradually away; anything that gradually slides out of sight belongs to the physical retina of the eye, and is not outside yourself. But if they dance up and down in every direction, exactly as the dust in a ray of light coming through a shutter, then you may be sure that you are seeing something in the air beyond your ordinary vision.