In human chemistry, Gustavus John Esselen (1888-1952) was an American chemist noted for being the consulting chemist for the 1948 book We Human Chemicals by Thomas Dreier, wherein he gave suggestions on chemical terms and analogies. 
Esselen completed his AB in chemistry (1909) and PhD in chemistry (1912), thesis: “Studies on Benzhydrols: I: The resolution of p-Aminobenzhydrol into its optical isomers, II: The splitting of Benzhydrols by the action of bromine”, both at Harvard University. 
The Gustavus John Esselen Award, which recognizes a chemist whose scientific and technical work, within the last five years, has contributed to the public well-being, and has thereby communicated positive values of the chemical profession, was established in Esselen’s honor in 1987 by the Northeastern Section of the American Chemical Society. 
1. Dreier, Thomas. (1948). We Human Chemicals: the Knack of Getting Along with Everybody. (section: Genesis of this Book, pgs. xiii-xv). Updegraff Press.
2. Gustavus John Esselen (biography) – American Chemical Society.
3. Gustavus John Esselen Award – Northeaster Section of the American Chemical Society.
● Esselen, Gustavus J. (1948). “There Are No Atheists in the Laboratory”, in Guideposts: Personal Messages of Inspiration and Faith, by Norman Peale, pgs. 183-87.
● Anon. (2005). “Gustavus John Esselen (1888-1952) and the Esselen Award” (pdf), The Nucleus, 83(8):4-5, Apr.
● Gustavus Esselen – Wikipedia.