The sphygmograph however, had to be attached directly to the wrist. By 1862 Marey had devised a way of transmitting movement through the air. He stretched a rubber membrane tightly over a tiny metal drum and connected it by hollow rubber tubing to another attached to a stylus. Any impulse given to the first "tambour", as the metal drums were called, was directly transmitted to the second and to the stylus marking the smoke-blackened cylinder.

La méthode graphique… (1885) p 446 La méthode graphique… (1885) p 460

La méthode graphique… (1885) p 357

This mode of transmission was the culmination of Marey's graphic method; all the instruments he created or developed after this, including his photographing and cinematographing instruments, comprised the same three elements: a sensitive sensor that would intercept the movement without interfering with it; a transmitter that would relay the movement through space; and a recording device that would make the motion permanent. Marey’s instruments rendered movement in its entirety: the only way they have been supplanted today is by the substitution of electrical or electronic transducers for the tambour-rubber-tubing apparatus that Marey used.