Born Mar. 8, 1879, in Greenwich; died Oct. 5, 1916. English physiologist; fellow of the Royal Society of London (1913).
Lucas graduated from Trinity College at Cambridge in 1901, where he joined the staff in 1904. In 1908 he began teaching the natural sciences. Lucas is known for his research on the electro-physiology of nerves and muscles. He proved that the wave of excitation in the normal nerve is propagated without attenuation, or decrement, but that there is a decrement in the narcotized or depressed nerve and in the synapses and myoneural junctions. By demonstrating that the reaction of a single muscle fiber is subject to the all or none law, he made that law applicable to the activity of the entire neuromuscular apparatus (1909).