Sunspots and telegraphy

Abstract

Above) The sun and sunspots, August 12, 1917, and (left) closer view of the granuluar surface of the sun Beyond the facts that they recur in welldefined cycles and that they affect certain of the earth's latitudes more than others, little but theoretical knowledge exists about the nature of sunspots and the sometimes con comitant magnetic storms· However, almost inadvertently, modern telegraph systems are being immunized against them b y such inno vations as carrier currents and radio relay systems which avoid the effects of earthcurrent disturbances.