FEW words are needed in sending this little book out into the world. It is the seventh of a series of Manuals designed to meet the public demand for a simple exposition of theosophical teaching. Some have complained that our literature is ,at once too abstruse, too technical, and too expensive for the ordinary reader, and it is our hope that the present series may succeed in supplying what is a very real want. Theosophy is not only for the learned; it is for all. It may be that among those who in these little books catch their first glimpse of its teachings, there may be a few who will be led by them to penetrate more deeply into its philosophy, its science, and its religion, facing its abstruser problems with the student's zeal and the neophyte's ardour. But these manuals are not written for the eager student, whom no initial difficulties can daunt; they are written for the busy men and women of the work-a-day world, and seek to make plain some of the great truths that render life easier to bear and death easier to face. Written by servants of the Masters who are the Elder Brothers of our race, they can have no other object than to serve our fellow-men.
So much confusion exists as to consciousness and its vehicles, the man and the garments that he wears, that it seems expedient to place before Theosophical students a plain statement of the facts so far as they are known to us. We have reached a point in our studies at which much that was at first obscure has become clear, much that was vague has become definite, much that was accepted as theory has become matter of first-hand knowledge. It is therefore possible to arrange ascertained facts in a definite sequence, facts which can be observed again and again as successive students develop the power of observation, and to speak on them with the same certainty as is felt by the physicist who deals with other observed and tabulated phenomena. But just as the physicist may err so may the metaphysicist, and as knowledge widens new lights are thrown on old facts, their relations are more clearly seen, and their appearance changes - often because the further light shows  that the fact which seemed a whole was only a fragment. No authority is claimed for the views here presented; they are offered only as from a student to students, as an effort to reproduce what has been taught but has doubtless been very imperfectly apprehended, together with such results of the observations of pupils as their limited powers enable them to make.
At the outset of our study it is necessary that the Western reader should change the attitude in which he has been accustomed to regard himself, and that he should clearly distinguish between the man and the bodies in which the man dwells. We are too much in the habit of identifying ourselves with the outer garments that we wear, too apt to think of ourselves as though we were our bodies; and it is necessary, if we are to grasp a true conception of our subject, that we shall leave this point of view and shall cease to identify ourselves with casings that we put on for a time and again cast off, to put on fresh ones when we are again in need of such vestures. To identify ourselves with these bodies that have only a passing existence is really as foolish and as unreasonable as it would be to identify ourselves with our clothes; we are not dependent on them - their value is in proportion to their utility. The blunder so constantly made of identifying the consciousness, which is our Self, with the vehicles in which that consciousness is for the moment functioning, can only be excused by  the fact that the waking consciousness, and to some extent the dream consciousness also, do live and work in the body and are not known apart from it to the ordinary man; yet an intellectual understanding of the real conditions may be gained, and we may train ourselves to regard our Self as the owner of his vehicle and after a time this will by experience become for a definite fact, when we learn to separate our Self from his bodies, to step out of the vehicle, and to know that we exist in a far fuller consciousness outside it then within it, and that we are in no sense dependent upon it; when that is once achieved, any further identification of our Self with our bodies is of course impossible, and we can never again make the blunder of supposing we are what we wear. The clear intellectual understanding at least is within the grasp of all of us, and we may train ourselves in the habitual distinguishment between the Self - the man - and his bodies; even to do this is to step out of the illusion in which the majority are wrapped, and changes our whole attitude towards life and towards the world, lifting us into a serener region above "the changes and chances of this mortal life," placing us above the daily petty troubles which loom so largely to embodied consciousness, showing us the true proportion between the ever-changing and the relatively permanent, and making us feel the difference between the drowning man tossed and buffeted by the  waves that smother him, and the man whose feet are on a rock while the surges break harmlessly at its base.
By man I mean the living, conscious, thinking Self, the individual; by bodies, the various casings in which this Self is enclosed, each casing enabling the Self to function in some definite region of the universe. As a man might use a carriage on the land, a ship on the water, an aeroplane in the air, to travel from one place to another, and yet in all places remain himself, so does the Self, the real man, remain himself no matter in what body he is functioning; and as carriage, ship and aeroplane vary in materials and arrangement according to the element in which each is destined to move, so does each body vary according to the environment in which it is to act. One is grosser than another, one shorter-lived than another, one has fewer capacities than another; but all have this in common - that relatively to the man they are transient, his instruments, his servants, wearing out and renewed according to their nature, and adapted to his varying needs, his growing powers. We will study them one by one, beginning with the lowest, and then take the man himself, the actor in all the bodies. 
THE PHYSICAL BODY
Under the term physical body must be included the two lower principles of man - called in our old terminology the Sthūla Sharīra and Linga Sharīra - since they both function on the physical plane, are composed of physical matter, are formed for the period of one physical life, are cast off by the man at death, and disintegrate together in the physical world when he passes on into the astral.
Another reason for classing these two principles as our physical body or physical vehicle is that so long as we cannot pass out of the physical world - or plane, we are accustomed to call it - we are using one or other or both of these physical vestures; they both belong to the physical plane by their materials, and cannot pass outside it; consciousness working in them is bound within their physical limitations, and is subject to the ordinary laws of space and time. Although partially separable, they are rarely separated during earthly life and such separation is inadvisable and is always a sign of disease or of ill-balanced constitution.
They are distinguishable by the materials of which they are composed into the gross body and the etheric  double, the latter being the exact duplicate of the visible body, particle for particle, and the medium through which play all the electrical and vital currents on which the activity of the body depends. This etheric double has hitherto been called the Linga Sharīra, but it seems advisable, for several reasons, to put an end to the use of the name in this relation. "Linga Sharīra" has from time immemorial been used in Hindu books in another sense, and much confusion arises among students of Eastern literature, whether Easterns or Westerns, in consequence of its arbitrary wresting from its recognized meaning; for this reason, if for no other, it would be well to surrender its improper use. Further, it is better to have English names for the subdivisions of the human constitution, and thus remove from our elementary literature the stumbling block to beginners of a Sanskrit terminology. Also, the name etheric double exactly expresses the nature and constitution of the subtler portion of the physical body, and is thus significant and therefore easy to remember, as every name should be; it is "etheric" because made of ether, "double" because an exact duplicate of the gross body - its shadow, as it were.
Now physical matter has seven subdivisions, distinguishable from each other, and each showing a vast variety of combinations within its own limits. The subdivisions are: solid, liquid, gas, ether, the latter  having four conditions as distinct from each other as liquids are distinct from solids and gases. These are the seven states of physical matter, and any portion of such matter is capable of passing into any one of these states, although under what we call normal temperature and pressure it will assume one or other of these as its relatively permanent condition, as gold is ordinarily solid, water is ordinarily liquid, chlorine is ordinarily gaseous. The physical body of man is composed of matter in these seven states - the gross body consisting of solids, liquids and gases; and the etheric double of the four subdivisions of ether, known respectively as Ether I, Ether II, Ether III, and Ether IV.
When the higher Theosophical truths are put before people, we find them constantly complaining that they are too much in the clouds, and asking: "Where ought we to begin? If we want to learn for ourselves and prove the truth of the assertions made, how are we to start? What are the first steps that we should take? What, in fact, is the alphabet of this language in which Theosophists discourse so glibly? What ought we to do, we men and women living in the world, in order to understand and verify these matters, instead of merely taking them on trust from others who say they know?" I am going to try to answer that question in the following pages, so that those who are really in earnest may see the earlier practical steps they ought to take - it  being always understood that these steps must belong to a life, the moral, intellectual and spiritual parts of which are also under training. Nothing that a man can do to the physical body alone will turn him into a seer or a saint; but it is also true that inasmuch as the body is an instrument that we have to use, certain treatment of the body is necessary in order that we may turn our footsteps in the direction of the Path; while dealing with the body only will never take us to the heights to which we aspire, still to let the body alone will make it impossible for us to scale those heights at all. The bodies in which he has to live and work are the instruments of the man, and the very first thing we have to realize is this: that the body exists for us, not we for the body; the body is ours to use - we do not belong to it to be used by it. The body is an instrument which is to be refined, to be improved, to be trained, to be moulded into such a form and made of such constituents as may best fit it to be the instrument on the physical plane for the highest purposes of the man. Everything which tends in that direction is to be encouraged and cultivated; everything which goes contrary to it is to be avoided. It does not matter what wishes the body may have, what habits it may have contracted in the past, the body is ours, our servant, to be employed as we desire, and the moment it takes the reins into its own hands and claims to guide the man instead of being  guided by the man, at that moment the whole purpose of life is subverted, and any kind of progress is rendered utterly impossible. Here is the point from which any person who is in earnest must start. The very nature of the physical body makes it a thing which can be turned fairly easily into a servant or an instrument. It has certain peculiarities which help us in training it and make it comparatively easy to guide and mould, and one of these peculiarities is that when once it has been accustomed to work along particular lines it will very readily continue to follow those lines of its own accord, and will be quite as happy in doing so as it was previously in going along others. If a bad habit has been acquired, the body will make considerable resistance to any change in that habit; but if it be compelled to alter, if the obstacle it places in the way be overcome, and if it be forced to act as the man desires, then after a short time the body will of its own accord repeat the new habit that the man has imposed on it, and will as contentedly pursue the new method as it pursued the old one to which the man found reason to object.
Let us now turn to the consideration of the dense body that we may roughly call the visible part of the physical body, though the gaseous constituents are not visible to the untrained physical eye. This is the most outward garment of the man, his lowest  manifestation, his most limited and imperfect expression of himself.
The Dense Body. — We must delay sufficiently long on the constitution of the body to enable us to understand how it is that we can take this body, purify it, and train it; we must glance at a set of activities which are for the most part outside the control of the will, and then at those which are under that control. Both of these work by means of nervous systems, but by nervous systems of different kinds. One carries on all the activities of the body which maintain its ordinary life, by which the lungs contract, by which the heart pulsates, by which the movements of the digestive system are directed. This is composed of the involuntary nerves, commonly called the "sympathetic system." At one time during the long past of physical evolution during which our bodies were built, this system was under the control of the animal possessing it, but gradually it began to work automatically - it passed away from the control of the will, took on its own quasi-independence and carried on all the normal vital activities of the body. While a person is in health, he does not notice these activities; he knows that he breathes when the breathing is oppressed or checked, he knows that his heart beats when the beating is violent or irregular, but when all is in order these processes go on unnoticed. It is, however, possible to bring the  sympathetic nervous system under the control of the will by long and painful practice, and a class of Yogi in India - Hatha Yogis they are called - develop this power to an extraordinary degree, with the object of stimulating the lower psychic faculties. It is possible to evolve these (without any regard to spiritual, moral or intellectual growth) by direct action on the physical body. The Hatha Yogi learns to control his breathing even to the point of suspension for a considerable period to control the beating of his heart, quickening or retarding the circulation at will, and by these means to throw the physical body into a trance and set free the astral body. The method is not one to be emulated; but still it is instructive for Western nations (who are apt to regard the body as of such imperative nature) to know how thoroughly a man can bring under his control these normally automatic physical processes, and to realize that thousands of men impose on themselves a long and exquisitely painful discipline in order to see themselves free from the prison-house of the physical body, and to know that they live when the animation of the body is suspended. They are at least in earnest, and are no longer the mere slaves of the senses.
Passing from this we have the voluntary nervous system, one far more important for our mental purposes. This is the great system which is our instrument of thought, by which we feel and move on the physical  plane. It consists of the cerebro-spinal axis - the brain and spinal cord - whence go to every part of the body filaments of nervous matter, the sensory and motor nerves - the nerves by which we feel running from the periphery to the axis, and the nerves by which we move running from the axis to the periphery. From every part of the body the nerve-threads run, associating with each other to make bundles, these proceeding to join the spinal cord, forming its external fibrous substance, and passing upwards to spread out and ramify in the brain, the centre of all feeling and all ...