The Department of Highways shall expend in each of the townships of the second class for the maintenance, construction, reconstruction, and repair of roads and bridges therein, not repaired and maintained by the Department of Highways under the provisions of any other law, such proportion of the total amount, hereinbefore provided, as the miles of streets or roads under its jurisdiction within its legal limits, and not maintained by the Department of Highways under the provisions of any other law, bears to the total number of miles of such streets or roads within the legal limits of all townships of the second class.
72 P.S. § 3564b