There are sounds which are musical, and others that are raucous and mere noise. The difference lies in the fact that harsh sounds are compounded of irregular vibrations, while the essence of Music is that its waves are rhythmic and follow each other in ordered swing. Rhythm is thus the primary manifestation of Music: but equally so it is the basic characteristic of everything in life. We learn that in Nature there is nothing still and inert, but that everything is in incessant motion. There is no such thing as solid matter. The man of Science resolved matter into atoms, and now these atoms themselves are found to be as miniature universes. Round a central sun, termed a Proton, whirl a number of electrons in rhythmic motion and incessant swing. And these electrons and protons--what are they? Something in the nature of charges of electricity, positive and negative. So where is now our seeming-solid matter? When this knowledge informs our outlook we see that all that lives, moves: and even that which never seems to move, lives also in continual rhythm and response. The eternal hills are vibrant to the eye of science, and the very stones are pulsing with the joy of life. The countryside sings, and there is the beat of rhythm not merely in our hearts but in every particle of our body. Stillness is a delusion, and immobility a fiction of the senses. Life is movement and activity, and rigidity and stiffness come more near to what we understand as death. Yet even in death there is no stillness, there is but a change in the form of activity. The body is no longer alive as an organised community, but in its individual cells: the activity is the liveliness of decomposition. Thus all the world expresses life, and expresses it in a rhythm in which law and order reign supreme, and in which a sweet and sane regularity is the ordinance. Regular rhythm involves accent. Whether or no there be any such emphasis as a thing in itself, the listening ear supplies it to meet a need. When we attend to a clock ticking, the tick-tock, tick-tock, however even it may sound at first, soon resolves itself into a rhythm with the accent on either the tick or the tock. So does the beat of an engine, or the hum of a railway train, merge itself into some definite sound picture, with the accent for relief that the ear demands. Thus out of rhythm grows very naturally an accentuation which gives balance, structure, and form. We start with the little units--the ticks and the tocks--and we build something bigger by grouping these together. This is a principle which we may see running through the activities of life in a thousand forms.