A regular visitor to the Salpêtrière from 1842 till his death more than thirty years later was Guillaume-Benjamin Duchenne de Boulogne (1806–1875). From humble provincial origins, a long line of seafarers from Boulogne, Duchenne became one of the outstanding medical scientists of the nineteenth century. Though he never held a senior appointment in the hospital, Duchenne nevertheless made meticulous observations on neurological patients, employing a wide range of innovative diagnostic techniques. Duchenne's clinical science stood at the junction of electricity, photography and psychology, as recorded in his much admired "De l'électrisation localisée" with its associated atlas "Album de photographies pathologiques" (1855, 1862). His name is commemorated in the myopathies which he described, as well as in his 1862 masterpiece, the "Mécanisme de la physionomie humaine", much consulted by Charles Darwin in the preparation of his "Expression of the Emotions in Man and Animals" (1872). Duchenne's last major work (published in 1867) was a study of the physiology of movement. He was never elected to the Academy of Sciences.