Developed in the 1830s and 1840s by Samuel Morse (1791 - 1872) and other inventors, the telegraph revolutionised long-distance communication. it worked by transmitting electrical signals over a wire laid between stations.
developed in the 1830s ( 1840s by samuel สึกหรอ ( 1791 จะ 1872 ) ( inventors ท่า the telegraph revolutionised communication long-distance . มันทำงานโดยการส่งสัญญาณไฟฟ้าผ่านลวดวางระหว่างสถานี