The fourfold discovery of Mescaline (1896–1919) Ivo Gurschler Chemical Monthly, 2019, 150, 941–947 © Springer-Verlag GmbH Austria, part of Springer Nature 2019 https://doi.org/10.1007/s00706-019-02444-0 Abstract This is an historical account of the pharmacological, chemical, and anthropological research concerning the molecular makeup of the peyote cactus (Lophophora williamsii) that laid the ground for Ernst Spaeth’s structural elucidation of mescaline as 3,4,5-trimethoxyphenethylamine. Keywords : History of science · Psychedelic studies · Organic chemistry · Alkaloids · Mescaline · Drugs   Introduction The exploration of the constituents of the peyote cactus and its effects upon the human psyche was an interdisciplinary undertaking that defied national borders. The material way to the heart of the [...]