time, a single-track spur line known as the "West Line" was constructed from the Libertyville branch at Lake Bluff into the city of North Chicago, where it terminated south of 22nd Street. In 1904, the Chicago and Milwaukee Electric began to purchase property and negotiate contracts for the extension of its service into Wisconsin. Construction between Waukegan and Zion City was largely complete by the summer of 1905. Further construction proceeded at such a pace that trains began operating as far north as Kenosha, Wisconsin by December of that year, followed by Racine in September 1906. Shortly thereafter, the Panic of 1907 forced the Chicago and Milwaukee Electric into a prolonged period of insolvency, but in spite of ongoing financial trouble, construction in Wisconsin continued. The northern extension was finally completed in 1908, with through service between Evanston and Milwaukee beginning that October. Though the Chicago and Milwaukee Electric had been placed under receivership in 1908, patronage and revenue continued to grow, permitting more improvements to the property. Bridges between Racine and Milwaukee were upgraded and the original mainline underwent significant rehabilitation, as did the street railway in Waukegan, which had since begun operating a line on Washington Street. New rolling stock was acquired, including an order of steel coaches delivered from the J.G. Brill Company in late 1915. The possibility of a direct entry into Chicago over the elevated lines was also studied during this time, with the intent to eliminate the necessity of transferring at Church Street, and thereby making the interurban service more competitive with the steam railroads. The Insull years When the North Shore Line assumed operations of the Chicago and Milwaukee Electric Railroad in 1916, it inherited an arrangement in which its trains operated on the Chicago and Evanston Line of the Chicago, Milwaukee and St. Paul Railroad south of Laurel Avenue in Wilmette to a terminal at Church Street in Evanston, where passengers transferred to and from Northwestern Elevated trains. In 1919, further trackage rights agreements were negotiated with both the Northwestern Elevated and the St. Paul Road which permitted North Shore Line trains to operate over the "L" south of Church Street, over the North Side Main Line and through the Loop, to a downtown terminal at Roosevelt Road. The following year, a new terminal in Milwaukee was dedicated, and in succeeding years, the remaining single-track in Wisconsin was eliminated, with the exception