58 



SYDNEY T. KLEIN ON THE INVISIBLE IS THE REAL, 



this is formed by thirty-two vibrations, and the next octave by 

 sixty-four vibrations, namely, by doubling the number for each 

 octave, and so on until we reach about the tenth octave, where 

 the pulsations are close on twenty thousand in a second, when 

 the sound^passes beyond the range of human audition, although 

 we can show that the air is still vibrating- and we can count 

 the number of beats and thence ascertain the pitch for another 

 three octaves. 



We now have to traverse numerically only about thirty-one 

 octaves, which contain all the pulsations"^ in the aether which we 

 use in wireless telegraphy and also those we appreciate as radiant 

 heat, and we then arrive at the rate of frequencies which, when 

 they strike the eye, gives us the impression of light. The lowest 

 rate gives us the colour red, followed by orange, yellow, green, 

 blue, indigo and violet. Colour in light is identical with pitch 

 in music, they both depend upon the rate of pulsation that 

 strike our organs of sight and hearing. 



If I had time I could have shown by means of the photo- 

 chromoscope that the colours red, green and violet are produced 

 by three rates of frequencies which are in exactly the same ratio 

 to each other as those of the first, third and fifth which compose 

 the major triad in music; and that those three colours when 

 combined produce pure white light. The whole range of sight 

 therefore only covers a little over half an octave, and above and 

 below this there is darkness for us ; and yet it is by means of 

 this about half an octave that we have to see all our surroundings. 

 AViiat a world of knowledge is therefore lost to us by the 

 narrowness of the slit through which we are able to look. We 

 can pej'haps understand our limitation in sight better if we think 

 what a world of sound would be lost to us if our range of hearing 

 only covered half an octave. It is true that we have invented 

 instruments which enable us to examine pulsations extending 

 slightly beyond visible light, and have indeed lately made a stride 

 by the discovery of the Eontgen Eays which are situated twelve 

 octaves above the violet light rays, but taking^ the total range of 

 our perception, we find that after all v/e are limited to what may 

 be called a few inches only on the long line of infinite extent, 

 reaching from the finite up to the infinite. 



Having thus realised the narrowness of our outlook and that 

 knowledge of the world of appearances is so entirely dependent 

 upon vibration or movement in the aether, air or matter, and that 

 without those vibrations we should have no knowledge of our 

 surroundings, we will carry our subject another step forward by 

 considering how that narrowness of outlook and our ignorance 

 surrounds us with illusions. 



One of the greatest illusions we have is what we call solidity 

 or continuity of sensation. If you hold a cannon-ball in your 



