Endocrinology's early historians (1889-1914) and the forgotten prehistory of testosterone.

Introduction: An often-retold historical outline of endocrinology was established over a century ago. An exhaustive history of sexual physiology remains forthcoming, however.

Objectives: To explore and contextualize the remarkable medical-historical and medical-anthropologic frenzy triggered by Brown-Séquard's 1889 self-injections with testicular juice, which ultimately settled down into an early history of endocrinology.

Methods: Pertinent primary sources were selected from a broader study, primarily between 1889 and 1914, as well as selected older texts identified and unidentified by these sources.

Results: Endocrinology's early historians in a short space of time moved from the history of testicular opotherapy to that of glandular typology and physiology and to increasingly encompassing medical-historical accounts of internal secretion as an epochal idea. Early historians nominated "precursors" to Brown-Séquard but underestimated physiologic continuities-specifically, early modern protoendocrinologic notions concerning semen as a "recrement," notions still recited by Brown-Séquard and early Brown-Séquardists as well their detractors. Brown-Séquard himself worked through this old (recremental) concept of semen between 1889 and 1892 but was later identified with it, by among others Ancel and Bouin.

Conclusion: Western sexual physiology is a medical palimpsest, the undertexts of which remain to be studied in detail.