“All the more recent work on alkaptonuria has... strengthened the belief that the homogentisic acid excreted is derived from tyrosine, but why alkaptonuric individuals pass the benzene ring of their tyrosine unbroken and how and where the peculiar chemical change from tyrosine to homogentisic acid is brought about, remain unsolved problems.”

“Science is not, as so many seem to think, something apart, which has to do with telescopes, retorts, and test-tubes, and especially with nasty smells, but it is a way of searching out by observation, trial and classification; whether the phenomena investigated be the outcome of human activities, or of the more direct workings of nature's laws. Its methods admit of nothing untidy or slip-shod; its keynote is accuracy and its goal is truth.”

“All the more recent work on alkaptonuria has... strengthened the belief that the homogentisic acid excreted is derived from tyrosine, but why alkaptonuric individuals pass the benzene ring of their tyrosine unbroken and how and where the peculiar chemical change from tyrosine to homogentisic acid is brought about, remain unsolved problems.”