ISBN-13: 9781508897750 / Angielski / Miękka / 2015 / 44 str.
ISBN-13: 9781508897750 / Angielski / Miękka / 2015 / 44 str.
When observing the spectrum formed by looking at a long vertical slit through a simple prism, I noticed an elongated dark spot running up and down in the blue, and following the motion of the eye as it moved up and down the spectrum, but refusing to pass out of the blue into the other colours. It was plain that the spot belonged both to the eye and to the blue part of the spectrum.