Journal of Physiology, 1904, v.31, pp. Proc. Physiol. Soc., xx-xxi
The first intimation of the chemical mediation of nerve impulses was given in Elliotts suggestion that when a sympathetic nerve impulse arrives at a cmooth-muscle cell it liberates adrenaline, which acts as a chemical stimulator.
Morton no.: 1336
Elliott, Thomas Renton, "On the action of adrenalin." (1904). Classic Article Collection. 190.