1850-1925. British physicist. In 1902 he
predicted the existence of an ionized layer
of air in the upper atmosphere, which was
known as the Kennelly-Heaviside layer but is
now called the E layer of the ionosphere.
Deflection from it makes possible the
transmission of radio signals around the
world, which would otherwise be lost in outer
space. His theoretical work had implications
for radio transmission. His studies of
electricity published in Electrical Papers
1892 had considerable impact on long-distance
telephony.