Darwin found in Crichton-Browne a fellow scientist sympathetic to his theories and ready to expound on his observations. The correspondence between the two men is colorful, replete with vignettes from Crichton-Browne’s blushing sister-in-law to the “observed hilarity” of women “labouring under erotomania, nymphomania, or any disorder of the sexual propensities” (Letter from JCB to CD, February, 16 1871). Though Crichton-Browne refers to very few of his photographs specifically, his letters flesh out the otherwise vacant personalities captured by his camera. In a single letter, he describes the “hilarity” of sexually perverse women; the “remarkable lachrymal secretion” of “melancholics, who sit rocking themselves rhythmically backwards and forwards”; and “a stereotyped smile” of “many idiots and imbeciles who are constantly smiling and laughing, who are `pleas[ed] with a rattle, tickled by a straw.’”