Section 3
SEC. 3. All telegraph and telephone lines and systems for the transmission of messages and signals by means of electricity owned, maintained, or operated by the grantees, their successors or assigns, shall be maintained and operated at all times in a complete, modern, first-class style as understood in the United States, and it shall be the further duty of said grantees, their successors or assigns, to modify, improve, and change such telephone and telegraph system, or systems, for the transmission of messages by means of electricity, in such manner and to such extent as the progress of science and improvements in the method of transmission of messages and signals by means of electricity may make reasonable and proper.