grow downwards, is twofold: to affect, and to be affected. In its active and positive condition it affects the whole of the vital and muscular processes in the body, finding expression in vital action. In its passive and negative state it is affected by impressions coming to it in different ways through the sense organs, resulting in nervous and mental action. These two functions are interdependent. It is the latter or afferent function with which we are now concerned. The range of our sense-perceptions puts us momentarily in relations with the material world, or rather, with a certain portion of it. For we by no means sense all that is sensible, and, as I have already indicated, our sense impressions are often delusive. The gamut of our senses is very limited, and also very imperfect both as to extent and quality. Science is continually bringing new instruments into our service, some to aid the senses, others to correct them. The microscope, the microphone, the refracting lens are instances. It used to be said with great certainty that you cannot see through a brick wall, but by means of X-rays and a fluorescent screen it is now possible to do so. I have seen my own heart beating as its image was thrown on the screen by the Rontgen rays. Many insects, birds and animals have keener perceptions in some respects than man. Animalculae and microbic life, themselves microscopic, have their own order of sense-organs related to a world of life beyond our ken. These observations serve to emphasise the great limitation of our senses, and also to enforce the fact that Nature does not cease to exist where we cease to perceive her. The recognition of this fact has been so thoroughly appreciated by thoughtful people as to have opened up the question as to what these human limitations may mean and to what degree they may extend.

We know what they mean well enough: the history of human development is the sequel to natural evolution, and this development could never have had place apart from the hunger of the mind and the consequent breaking down of sense limitations by human invention. As to the extent of our limitations it has been suggested that just as there are states of matter so fine as to be beyond the range of vision, so there may be others so coarse as to be below the sense of touch. We cannot, however, assert anything with certainty, seeing that proof must always require that a thing must be brought within our range of perception before we can admit it as fact. The future has many more wonderful revelations in store for us, no doubt. But there is really nothing more wonderful than human faculty which discovers these things in Nature, things that have always been in existence but until now have been outside our range of perception. The ultra-solid world may exist.

The relations of our sense-organs to the various degrees of matter, to solids, fluids, gases, atmosphere and ether, vary in different individuals to such a wide extent as to create the greatest diversity of normal faculty. The average wool-sorter will outvie an artist in his perception of colour shades. An odour that is distinctly recognizable by one person will not be perceptible to others. In the matter of sound also the same differences of perception will be noted. On a very still night one can hear the sugar canes growing. Most people find the cry of a bat to be beyond their range. The eye cannot discern intervals of less than one-fiftieth of a second. Atmospheric vibration does not become sound until a considerable frequency is attained. Every movement we make displaces air but our sense of touch does not inform us of it, but if we stand in a sunbeam the dust particles will show that it is so. Our sense of feeling will not register above certain degrees of heat or below certain degrees of cold. Sensation, moreover, is not indefinitely sustained, as anyone may learn who will follow the ticking of a watch for five minutes continuously.

But quite apart from the sense and range of our perceptions, the equality of a sense-impression is found to vary with different persons, affecting them each in a different way. We find that people have "tastes" in regard to form, colour, flavour, scent, sound, fabric and texture. The experience is too general to need illustration, but we may gather thence that, in relation to the nervous system of man, every material body and state of matter has a variable effect. These remarks will clear the ground for a statement of my views upon the probable effect a crystal may have upon a sensitive person.

CHAPTER II.

MATERIALS AND CONDITIONS

The crystal is a clear pellucid piece of quartz or beryl, sometimes oval in shape but more generally spherical. It is accredited by Reichenbach and other researchers with highly magnetic qualities, capable of producing in a suitable subject a state analogous to the ordinary "waking trance" of the hypnotists. It is believed that all bodies convey, or are the vehicles of certain universal property called od or odyle (od-hyle), which is not regarded as a force but as an inert and passive substance underlying the more active forces familiar to us in kinetic, calorific and electrical phenomena. In this respect it holds a position analogous to the argon of the atmosphere, and is capable of taking up the vibrations of those bodies to which it is related and which it invests. It would perhaps not be amiss to regard it as static ether. Of itself it has no active properties, but in its still, well-like depths, it holds the potentiality of all magnetic forces.

This odyle is particularly potent in certain bodies and one of these is the beryl or quartz. It produces and retains more readily in the beryl than in most other bodies the images communicated to it by the subconscious activity of the seer. It is in the nature of a sensitized film which is capable of recording thought forms and mental images as the photographic film records objective things. The occultist will probably recognize in it many of the properties of the "astral light," which is often spoken of in this connection. Readers of my Manual of Occultism will already be informed concerning the nature of subconscious activity. The mind or soul of man has two aspects: the attentive or waking consciousness, directed to the things of the external world; and the subconscious, which is concerned with the things of the interior world. Each of these spheres of the mind has its voluntary and automatic phases, a fact which is usually lost sight of, inasmuch as the automatism of the mind is frequently confounded with the subconscious. All purposive action tends to become automatic, whether it be physical or mental, sensory or psychic.

The soul in this connection is to be regarded as the repository of all that complex of emotions, thoughts, aspirations, impressions, perceptions, feelings, etc., which constitute the inner life of man. The soul is none the less a fact because there are those who bandy words about its origin and nature.

Reichenbach has shown by a series of experiments upon sensitive and hypnotized subjects, that metals and other materials produce very marked effects in contact with the human body. The experiments further showed that the same substance affected different patients in diverse manners.

The hypnotic experiments of the late Dr. Charcot, the well-known French biologist, also demonstrate the rapport existing between the sensitive subject and foreign bodies in proximity. A bottle containing a poison is taken at random from a number of others of similar appearance and is applied to the back of the patient's neck. The hypnotic subject at once begins to develop all the symptoms of arsenical, strychnine or prussic acid poisoning; it being afterwards found that the bottle contains the toxine whose effects have been portrayed by the subject. But not all hypnotic subjects are capable of the same degree of sensibility.

Community of sensation is as common a phenomenon as community of thought between a hypnotizer and his subject, and what are called