Whenever two railroad companies shall, for a portion of their respective lines, embrace the same location of line, they may by agreement provide for the construction of so much of said line as is common to both of them, by one of the companies, and for the manner and terms upon which the business thereon shall be performed. (1871-2, c. 138, s. 46; Code, s. 1983; Rev., s. 2602; C.S., s. 3473; 1963, c. 1165, s. 1; 1998-128, s. 14.)