Electro-Physiologie; Figure 64; 1854-56; printed 1862; Albumen silver print from glass negative; Image: 29.8 x 22.3 cm (11 3/4 x 8 3/4 in.); Photographs; Adrien Tournachon (French; 1825-1903); Guillaume-Benjamin-Amand Duchenne de Boulogne (French; 1806-1875); In compiling a scientific treatise to aid artists; the physiologist Duchenne de Boulogne used electrical stimulation of the facial muscles to elicit expressions of the principal emotions. Wanting his transcriptions to be exact; he collaborated with Adrien Tournachon (brother of the famous Nadar); a photographer who specialized in portraiture