Super-sensible Vibrations


Moreover, as every text book on science informs us, there are sounds too

low as well as those too high for the human ear to register, but which

are registered by delicate instruments. Again, there are colors beyond

the place of red, at one end of the visible spectrum; and others beyond

the place of violet at the other end of that spectrum, which the human

eye is unable to register and detect, but which our apparatus in the

laboratory plainly register. The ray of light which registers on the

photographic plate, and which causes sunburn on our skin, is too high a

rate of vibration for our eyes to perceive. Likewise the X-Rays, and

many other of the finer rays of light known to science are imperceptible

to the unaided human vision--they are actually "dark rays" so far as the

human eye is concerned, though man has devised instruments by means of

which they may be caught and registered.



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