Find out what an odor is - whether it is an emanation and therefore subject to being weighed, or a vibration and therefore capable of being reflected. Odors are becoming more and more important in the worlds of scientific experiments and in medicine - and the need of more knowledge will bring forth more knowledge, as sure as the sun shines.

In: N.E. McIndoo, Annual Report of the Board of Regents of the Smithsonian Institution, (1920)