"The construction of the roads is to be done in the States, subject to approval of the United States Secretary of War, and future federal aid will be withheld from the States in the same manner as in the case of the roads. The State, with high-way development, will be affected by the construction of the roads, and with the practical conviction that the construction of the roads is taken for the most part time there will be great men to fill all the essential work. 