|….In other words, the petal absorbs the yellow region of the spectrum strongly, whereas the rest of the spectrum is let through the different regions therein exhibiting the same relative intensities as in the incident light. Another method of examination is to view the petal in sunlight by reflection instead of by transmission. The spectrum seen in this way represents the colour of the flower more nearly than the spectrum observed by transmission. Actually, however, in the particular case, there is no noticeable difference in the characters of the observed spectra…..|
"When you can measure what you are speaking about, and express it in numbers, you know something about it, when you cannot express it in numbers, your knowledge is of a meager and unsatisfactory kind; it may be the beginning of knowledge, but you have scarcely, in your thoughts advanced to the stage of science."